Is Betelgeuse about to blow?

By Phil Plait | June 1, 2010 3:43 pm

eso_betelgeuseI was going to wait to write about this, but I’m getting a lot of emails about it, so I’ll say something now, and followup when I get more information.

The story:

BABloggee Alereon (and many others) sent me to an interesting site: Life After the Oil Crash Forum — a forum that apparently has a lot of doomsday-type scuttlebutt posted to it.

An anonymous poster there says he has heard that the star Betelgeuse is about to go supernova, maybe as soon as a few weeks:

I was talking to my son last week (he works on Mauna Kea), and he mentioned some new observations (that will no doubt get published eventually) of “Beetlejuice”; it’s no longer round. This is a huge star, and when it goes, it will be at least as bright as that 1054 supernova…except that this one is 520 light years away, not 6,300 [...]

When it collapses, it will be at least as bright as the full moon, and maybe as bright as the sun. For six weeks. So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky. The extra hour of light from daylight savings time won’t burn the crops, but this might. Probably, all we’ll get is visible light (not gamma rays or X-rays), so it shouldn’t be an ELE. It’s sure gonna freak everyone out, though…..

Then it will form a black hole, but we’re too far away for that to matter.

The buzz is that this is weeks/months away, not the “any time in the next thousand years” that’s in all the books.

The basic takeaway:

OK, folks, first: when news like this comes from an unnamed source on some random forum, and that source is not even a primary one, and that secondary source quoted is also unnamed, and that person heard it from a third party that is also unnamed… well, oddly enough my skeptic alarm bell in my head rings loudly enough that my eardrums explode outward in every direction at the speed of light.

I hope I’m being clear here.

The first important thing to note here is that if Betelgeuse explodes, we’re in no danger at all. It’s too far away to hurt us. Got that? It’s the most important thing to remember here, because I’m quite sure this story will get wildly exaggerated as it gets repeated.

So, what’s the deal with Betelgeuse? What is it, will it explode, and if so, when?

The details:

Betelgeuse is one of the brightest stars in the sky. That’s because it’s an intrinsically luminous star, and one that’s relatively close by. By luminous, I mean something like 100,000 times that of the Sun, and by close I mean roughly 600 light years away if not more. That’s 6 quadrillion kilometers, or almost 4 quadrillion miles. In other words, quite a hike.

Betelgeuse is a red supergiant. It has a mass of something like 20 times the Sun’s, and is near the end of its life. When it dies, it will explode as a supernova, a titanic event that is among the most violent in the Universe. For details on how this happens, read this essay I wrote about it.

It’s hard to know just when a star will explode when you’re on the outside. Betelgeuse might go up tonight, or it might not be for 100,000 years. We’re just not sure.

Betelgeuse isn’t round, and it’s shrinking!

In the bulletin board post, he talks about the star not being round. It’s unclear, but it sounds like he’s referring to observations which show that there is a big plume coming from the surface of Betelgeuse. That was exciting news when it was released, but not hugely surprising; stars are active, and massive stars even more so. Also, note that those "new" observations are a year old!

hst_betelgeuse

That image above is from even earlier, and shows a Hubble observation of Betelgeuse taken in 2005. Note here that the star doesn’t look round, but that’s an illusion. The image shows a hot spot in Betelgeuse’s swollen atmosphere, and that makes it look like a bump is hanging of the side. In reality, that’s just because of the way the image is printed, and isn’t an actual physical bump. But the hot spot (probably due to a big ol’ bubble of hot gas rising near the surface) in itself shows that things on the star change all the time; just recently two such spots were found.

The post also talks about Betelgeuse shrinking. That claim is from observations made over the course of many years. Those data indicate the star is shrinking, but it’s unclear what they mean. While it may mean the star is in fact shrinking, starspots (sunspots on another star) may be fooling us, for example. Also, red supergiants aren’t like marbles, with a clean, sharp surface. They are balls of gas, extended and bloated, so there is no real surface. It’s therefore entirely possible the astronomers aren’t even really measuring the surface of the star at all, and it’s just the highly extended atmosphere that’s changing.

Surface tension, rotten to the core

The point I’m making is that a lot of stuff can happen on the surface of the star that has nothing to do with the core. Since it’s the core that generates the star’s energy and eventually causes it to explode, what’s happening on the surface is not an indication of any impending explosion.

Mind you, the surface and the core do "talk" to each other, though slowly. As the core changes, that information does leak to the surface, but it takes centuries. Until, that is, the core collapses. When that happens, the shock wave takes hours or days to get to the surface, and the star explodes. But that’s hardly a slow event taking decades! So any changes we see happening now probably have little to do with what’s happening hundreds of millions of kilometers deep in the star.

Also, it’s been known for a long time that Betelgeuse is a variable star; its light output changes. This shrinking may just be a part of that natural cycle, and again no indication of an explosion.

Having said all that, I’ll note that someday, Betelgeuse will explode. That’s for certain! But it’s also way too far away to hurt us. A supernova has to be no farther than about 25 light years away to be able to fry us with light or anything else, and Betelgeuse is 25 times that distance (which means its power to hurt us is weakened by over 600x). It’s the wrong kind of star to explode as a gamma-ray burst, so I’m not worried about that either.

At that distance, it’ll get bright, about as bright as the full Moon. That’s pretty bright! It’ll hurt your eyes to look at it, but that’s about it. The original post says it may get as bright as the Sun, but that’s totally wrong. It won’t even get 1/100,000th that bright. Still bright, but it’s not going to cook us. Even if it were going to explode soon. Which it almost certainly isn’t.

Conclusion:

So my personal opinion is that this is just another breathless rumor of astronomical doomsday that we get every couple of years. Even if any of the science of it is right, it doesn’t mean Betelgeuse is about to explode any day now. And since this is a rumor three times removed, I don’t put any stock in it. I’ll wait until I hear from named scientists with published or publishable data before I start to wonder if the star is about to blow.

And if and when it does explode, it can’t hurt us. Someday it will — maybe not for a hundred thousand years, but someday — and every astronomer on the planet hopes it happens in their lifetime! It will be a scientific bonanza unlike any ever seen.

Image credits: NASA, ESA, ESO

Comments (254)

Links to this Post

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  1. Robert
  2. Carney Wilson

    And here I was, hoping we would see its explosion on 2010/12/21 so we could giggle amongst ourselves.

  3. I just love this in the original forum post: ” The extra hour of light from daylight savings time won’t burn the crops”. Shows a complete failure to understand DST. :D

  4. Let’s suppose just for the sake of rough argument that when Betelguese goes it will be 100 billion times brighter than the sun. That’s not an unusual brightness for a supernova; they can often rival an entire galaxy.

    On the other hand, Betelguese is a lot farther away. At the speed of light, the sun is 8 minutes away. At the speed of light, Betelguese is 600 light years away. I estimate that is is therefore approximately 2.4 trillion times farther than the sun (600 years converted to minutes, divided by 8). And the intensity of light falls off as the square of the distance. So while it is intrinsically 100 billion times brighter than the sun, it is at the same time going to be 5.6 x 10 ^18 times dimmer because it is farther. The net effect is that Betelguese will wind up far, far dimmer than the sun as seen from earth. Something like 56 million times dimmer when both factors are taken into account.

    Now, that’s a bright thing in a night sky. But it isn’t going to rival the sun in brightness.

  5. Matt

    If we all saw it explode today, would that mean it actually went supernova 600 years ago?

  6. John

    For the time being, everyone sees betelgeuse during the day (give half an hour or so?) since its so close to the sun. The “people who’d see it at night?” – what, if the sun was revolving around the earth?

    I’ve been having dreams for a few months of betelgeuse blowing up.. but when I think about it, its for the following reasons: 1. I just got back into science/astronomy after a long absence and want to see a supernova, and like everyone agrees, depending on the time of year, it’ll be quite a show… 2. It will blow up some day… 3. I will be kinda sad when it does.

    Anyway, the size of the outer layers will tell you something about the output of the star v time… but really, when the star gets to silicon burning – the time the star will have available to contract (the thing is AUs big) before it blows up will be about a day.

    Phil, is it likely at that point we’d really see any sign of it? Say the star made it down to 6 AU diameter (from about 10? my gut tells me thats an absurdly optimistic estimate – thats a pretty high fraction of c) in a day – won’t most of its increased output be in the infrared? Will its apparent brightness increase enough to counteract that its smaller?

    I still need to learn the math on it, but I have a hunch that when it goes, there won’t be much of a warning. There is a huge volume of star that is only vaguely in-touch with what is going on at the core…

  7. BILL7718

    I heard during the discover channel show about stars that once a star starts producing iron it explodes. I also remember them saying that all elements besides hyrdogen were formed inside stars. Are the elements heavier than iron somehow formed during the explosion of stars?

    An another note, Betelgeuse won’t explode unless that guy posts his prediction 3 times. Everybody knows that.

  8. Well my hopes are dashed. Still hopefully it will explode while I’m still around.

  9. Cairnos

    So when it does blow, do we have any idea how long it will hang around in the sky for? I’m guessing it won’t be a ‘blink and you miss it’ type event.

  10. Kevin

    Now, if in the original story Phil talked about, the author said it was his father’s brother’s nephew’s cousin’s former roommate then I’d take it seriously.

    I wonder if this is going to be the new “Mars will be as big as the Moon” thing going around every year now.

    (Of course, it’s getting to be time for that to surface again anyway.) :(

  11. Kullat Nunu

    That image above is from even earlier, and shows a Hubble observation of Betelgeuse taken in 2005.

    Actually, as you can see, the picture is much older, taken in 1995.

  12. Gray

    Would some kind person clarify light years for this lowly biologist? Specifically, if we find out about a plume on the surface of Betelgeuse (or its explosion, for that matter) right now, and the star is 600 light years away, doesn’t that mean that the event actually occurred 600 years ago? Or do I have it all wrong?

  13. Cairnos

    @kevin – Be pretty cool if a) that (somehow) came true and b) happend at the same time as we saw betelgeuse blow. I imagine that would do wonders for astronomies popularity…we’ll amongst those who weren’t huddled in a church waiting for the rapture anyway

  14. Kent

    @Bill7718 You are correct, all heavier elements than Iron are formed in supernovae, and as such are exceedingly rare.

    http://en.wikipedia.org/wiki/Supernova_nucleosynthesis

  15. cody

    I just hope its already happened and I get to see it in my lifetime because it will be spectacular sight.

  16. Keith (the first one)

    Would it even be possible to have a star so huge that when it goes supernova it would appear as bright as the sun from Earth?

  17. Keith Harwood

    Klopfer @2.

    What! Do you mean the farmers don’t put the crops away at night and bring them out again in the morning? They leave them out all night? By themselves?

  18. JBBW

    I heard that the radiation will be so weak and pushed into the blue end of the spectrum that it will only burn republicans.

  19. Would it even be possible to have a star so huge that when it goes supernova it would appear as bright as the sun from Earth?

    Sure. As long as it’s so close to us that the shockwave would destroy our planet, and so huge, it would exceed the Eddington luminosity limit. If it existed, it would be the brightest object in the night sky today, even brighter than the Moon.

  20. gwensdad

    But what about Ford Prefect!?

    (shocked it took so long until the first Hitchhiker’s Guide reference)

  21. humble reader

    @BILL7718 elements heavier than H, He and Li are generated in stars,
    up to about Fe. Heaver elements are produced during supernovae,
    primarily via nucleon capture.

    Here’s hoping for an imminent explosion, at ~300 times closer than
    SN1987a there should be a beautiful neutrino pulse for IceCube and Co.

  22. alfaniner

    As long as nobody says its name three times in a row, we’re safe.

  23. Harry

    “I estimate that is is therefore approximately 2.4 trillion times farther than the sun (600 years converted to minutes, divided by 8).”

    Huh?
    600×365*1440=315360000 = minutes in 600 years
    divide by 8 to compare with sun’s distance.
    =39420000
    Around 40million times as far, not 2.4trillion times as far???

    It seems you worked out the number of milliseconds in 600 years and then didn’t divide by 8 minutes?

  24. Jo

    Heh, my favourite version of the Twitter telephone game for this one was something along the lines of, “BETELGEUSE IS GOING TO CRASH INTO OUR SOLAR SYSTEM!!!111!!!!”

  25. Brian

    If it blows, it should be nice and shiny for about 3 weeks, if memory serves.

  26. @ Klopfer:

    That daylight savings time line leaped out at me, too.

    I remember when the Carter administration voted to extend daylight savings time in an attempt to save energy, there were loud cries of, “But you’re messing up god’s time!”

    I would classify this one with the annual “Mars is going to appear as big as the full moon” emails.

  27. Poor Orion is going to have his shoulder blown completely apart. Let’s see you hunt then, Orion! Not only is the earth doomed but you will no longer be capable of protecting the skies! We really are doomed.

  28. Dave Regan

    bump is hanging of the side
    =>
    bump is hanging *off* the side

    Another amusing thing in the rumor:


    Then it will form a black hole, but we’re too far away for that to matter.

    Given that a super nova won’t increase the mass of the star, any gravitational differences to us will be exactly 0.

  29. cc

    Jeff Adkins said:
    “I estimate that is is therefore approximately 2.4 trillion times farther than the sun (600 years converted to minutes, divided by 8). ”

    I have no idea how you arrived at 2.4 trillion. This seemed so far out of my estimates that I googled it. I get 3.9 million. Roughly a million-fold less.

    http://www.google.com/search?q=75+years+in+minutes

  30. Ken Mitchell

    @BILL7718; When light atoms such as hydrogen or helium fuse together to make heavier atoms, it releases energy. When heavy atoms, such as uranium or plutonium FISSION, or split apart to create lighter elements, it releases energy. So somewhere in between is the “low point” in the energy curve. The low point is iron. When atoms fuse into anything heavier than iron, it CONSUMES energy, sucking heat out of the core of the star. That’s when the star explodes, from a combination of energy being removed from the core, which then permits the core to collapse further, accelerating the process. The only thing stopping ANY star from collapsing is the balance between the internal heat and pressure trying to blow it up (it’s a star, it’s a nuclear explosion!) and the tremendous gravity of its own mass.

    The heavy atoms, at least some of them, are then thrown back into space as the star goes supernova. This has been long known; the iron atoms in your hemoglobin were created in such a supernova explosion before the formation of the planetary nebula that later became our solar system. In fact, every atom heavier than lithium has already been through a star at least once.

    So will Betelgeuse go supernova? Yes. Will it do so in our lifetimes? Damifino. It could blow at any time! Or it might not. It’ll be a lovely sight when it does, and frankly, I’d like to see it.

  31. Zucchi

    But — I heard! A guy said! And, there’s buzz! Damn it, you can’t refute buzz!

    (Note: It’s Daylight Saving Time. No such thing as Daylight Savings Time.)

  32. Phil’s blown this one out of the water in his own effective style, so they’ll start looking for something else under 25 light years away. As nasty little things such as Chandrasekhar masses won’t bother them (why let science get in the way?) I’ll go with a Type Ia supernova from the detonation of white dwarf Sirius B…

    If only they could just accrete a little knowledge!

  33. AliCali

    “The extra hour of light from daylight savings time won’t burn the crops, but this might.”

    Right now, daylight saving is only one hour. How long before Congress declares a 12-hour daylight saving and they legislate away nighttime?!

    Hey, if they can legislate away Global Warming, why not the night?

  34. Geoff

    As far as I understand these things, if you say it is about to happen, it is more likely to happen. So please say it is because it would be cool.

    Geoff

  35. TW

    Breaking news:

    “Astronomer Dr Phil Plait says he is certain Betelgeuse is going to EXPLODE!!!!!…but first a word from our sponsors…”

  36. Betelgeuse is only 20 times the mass of the sun, and a quick WolframAlpha calculation tells me it is 3.3 x 10^9 times the volume. What does that make its density? My calculations are getting something insanely low. To me this would tend to support the “extended atmosphere” theory Phil suggested.

  37. this_isn't_fair

    I wanted to see a supernova :(

  38. Chris A.

    As Phil alludes, it’s fairly meaningless to speak of the “surface” of a red super giant.

    I recall my college astronomy days, when I learned the Lane-Emden equation: Using some very simple principles of pressure, gravity, etc., one can approximate the internal structure (density and pressure as a function of radius) of a star. A lone parameter (the polytropic index, n) can take on various values to model different types of stars. The supergiant was best modeled with n=5, which corresponded to a star of infinite extent (i.e. no surface–its density and pressure only dropped to zero at infinity).

    So, when I hear about Betelgeuse “shrinking” or being “lumpy,” I take it with a big, polytropic grain of salt. It’s roughly the equivalent of claiming the Earth is grows every 11 years because the upper layers of the atmosphere puff up a bit around solar maximum.

  39. Old Rockin' Dave

    @Keith:
    “What! Do you mean the farmers don’t put the crops away at night and bring them out again in the morning? They leave them out all night? By themselves?”
    They do, but they turn them a quarter-turn before they go to bed. Haven’t you ever heard of crop rotation?

  40. john

    I also found
    “So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky. ”
    to be rather amusing.

  41. Of course the supernova will not be visible in Wisconsin or Texas, being unlawful there.

  42. Scottynuke

    Did I stumble into a reading of “Death From the Skies” or something? :-)

  43. Kevin F.

    Let’s not forget that the light we’re seeing from Betelgeuse left it when the Black Plague was still raging here and there.

  44. Matt

    Why anyone would trust the forum post cited in the article is a mystery. Claiming that the “extra hour of sunlight from Daylight Savings Time” would “burn crops” is so dumb that even Sarah Palin thinks it’s retarded.

  45. Bad Albert

    For all those who complain that Phil never posts about bad astronomy, take that!

    Anyway, thanks for the heads-up Phil. Now I know it’s only a matter of time before I get another doomsday email forwarded by my mother warning about this imminent event.

  46. Hasn’t the “Betelgeuse is about to blow” rumour been floating around for decades now? I remember Isaac Asimov writing about it in a science book that came out in the 1970s, I think.
    Explode, already!

  47. rabidmob

    I would like to start the, “Betelgeuse has already exploded, we just don’t know rumor.”

    Since it’s > 500 light years away it could of exploded long ago and we still wouldn’t know.

  48. Michael Tinsley

    @ jeff adkins: light travels (approx) 6 tillion miles/year. Its easier to multiply that by 600 than to convert 600 years to minutes and divide by 8.

  49. Michael Tinsley

    Actually, its 8.33 minutes from Sun to Earth at an average distance of 93,000,000 miles.

  50. Tom

    Geez you are thick mr author.
    “he mentioned some new observations of “Beetlejuice”; it’s no longer round.”
    Yes, it is no longer round because the latest images are more sensitive so can capture it in better resolution in its bulbous form, rather than a blurry round star as previously seen.

    So no need to get your knickers in a twist

  51. AliCali

    @ 40: “I also found ‘So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky.’ to be rather amusing.”

    Why? If the sun is out when Betelgeuse explodes, you’ll have two suns. But if it’s nighttime, then you’ll get a temporary, nighttime sun. Jeez, it’s so simple! This is why NASA launches solar-observing satellites in the daytime.

  52. Oh but wouldn’t it be cool to see? Explodey stuff is always awesome … Dr P, is there anything we can do to speed up the process :)

    And living in the southern hemisphere, we won;’t get 24 hour days (dammit!) but the lightshow will still be very impressive, Orion being very visible for about 2 hours after sunset atm :D

  53. Brett Buck

    Well, I am going to keep wearing aluminum foil on my head, just in case.

  54. Ang

    OK – I just can’t help myself on this nucelosynthesis thing.

    1) most elements heavier than carbon, not iron, are made in supernovae – but not all. Although a star like the sun can only make elemetns up to carbon efficiently, the process of slow neutron capture during the second red giant phase (AGB phase) can make all elements up to lead, and will make some elements efficiently (e.g. Technecium; Zirconium).
    2) Betelgeuse will be a type II supernova. Most iron comes from Type 1a supernovae – which are formed when a white dwarf (from a sunlike star) accretes mass from a companion and then goes boom. Type II supernovae are most efficient at making alpha-rich elements up to silicon – but the iron made in the core gets destryed during the formation of the nurton star or black whole remnant.

    In both types of Supernovae, elements heavier than iron are made by neutron capture but it happens really fast in the explosion and consequently makes different isotopes and different ratios of elements that the slow process in AGB stars…

    (And yes I can find references if I really have to)

  55. Crudely Wrott

    ‘Course, if it has already blown within the last, say, five and a half, six hundred years, we couldn’t know just now.

    Betelgeuse! Betelgeuse! Betelgeuse!

    *now I’ve done it*

  56. Ryan

    @Gray:

    To answer your question, you’re right. What happens on Betelgeuse today won’t be detectable by us for about another 600 years. Conversely, if Betelgeuse already went supernova 600 years ago, we should be in for a visual treat any time now.

  57. JadeyWeb

    The comments about this blog are the funniest things I’ve read all year.
    :-)

  58. Darn it! No explotions? so, will I have to go tomorrow to work? haha!

  59. Alex

    The thing is, if it exploded now, I’m pretty sure none of us would see it. It’s 600 light years away, so it would take basically 600 year for the light given off by the supernova to get here. In fact, for all we know it could have gone supernova anywhere between now and 600 years ago.

  60. Alex

    Er, sorry. Didn’t realize someone just said that already.

  61. Ari

    36:
    That sounds about right:

    http://www.aavso.org/vstar/vsots/1200.shtml

    “The outer edge of Betelgeuse’s circumstellar envelope extends well over a trillion kilometers from the star — so light from the star takes a good two months to escape the gas shell. In the outer reaches of this vast globe, the density is extremely low. In volume, Betelgeuse exceeds the Sun by a factor of at least 160 million even at minimum. Yet the actual mass of the star is probably no more than about 20 solar masses, which means that the average density must be in the range of .00000002 to about .00000009 the density of our Sun. Such star material has a density of less than one ten-thousandth the density of ordinary air. A star of such tenuous nature has often been called a “red-hot vacuum” (Burnham, 1966). ”

    Damn you, Phil for getting me all excited briefly with that post title!

  62. kebsis

    I really, really hope that the crack about daylights savings time was a joke…

    Question; Theoretically, if Betelgeuse were to explode, would it leave a more or less permanent fixture in the sky? It would be amazing to be able to look up at the sky at night and see the remains of a super massive star with the naked eye.

  63. alkabitous

    it probably already has exploded, we just won’t know it for a few hundred years!

  64. Disappointed Debbie

    And here I was hoping this would rile up the 2012 Maya conspiracy nuts. Oh well.

  65. Christian Ott

    I am a supernova theorist, so, naturally, I’d just love to see Betelgeuse go sooner than later!

    The truth about this story is, unfortunately, that we don’t know. We don’t understand stellar evolution well enough to make predictions on what precisely is going on in Betelgeuse’s core right now (or rather, right now, ~600 years ago). There appear to be some indications that it is burning carbon (this is from a talk I saw two years ago at the APS April meeting in St. Louis). This would mean that it had ~100-1000 years of life or so. But only if the claim about it burning C is right. But even then, we’d only be able to pinpoint its time of explosion to a factor of 10…

  66. stelei

    @kebsis:
    Of course there’ll be a permanent fixture – that’s where some of the gorgeous nebulae in the sky come from! The Crab nebula is a textbook example. But (so far!) all supernova remnants require telescopes to be seen, having had thousands of years to expand and cool after the initial explosion.

  67. alfaniner

    “So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky.”

    I can’t help but imagine some desert farm boy looking out at the two suns, wondering if there is a better life “out there”.

  68. John S

    WE ARE ALL GOING TO DIE!

    This will probably not affect that fact however.

  69. eyelessgame

    So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky.

    Can I be a pedant for a bit? Except on the poles, everyone will pretty much have the same experience when Betelgeuse explodes: if it explodes in January, we’ll get six weeks of nova-bright nights; if it explodes in June, we’ll get a visible spot to the south of the Sun. One of the red flags that the email isn’t terribly reliable is that the author seems to think that at a given time some parts of the planet see Betelgeuse all night while others don’t. (In June, parts of Antarctica would see Betelgeuse just above the horizon for a few hours out of each twenty-four, during the months-long night – but that’s the sole exception.)

    So, oh well. A shame. Imagine Orion losing his shoulder forever!

  70. Andback

    I want my supernova, and I want it now!

  71. Darn scientists always trying to ruin our doomsday-type scuttlebutts. Ah well, plenty more where that came from, I suppose.

  72. Richard

    What we should be concerned about is the effects of life on Earth after Phil’s “eardrums explode outward in every direction at the speed of light”. That’s not a world I want to live in! :-)

  73. Redneck Hick learned

    Shoot, that redneck hick and his son who is all learned are givin all us other redneck hicks with sum edukation a bad rep…rep….darn it, you know that word, the one where you call your corn county queen during your high school years and it tarneshees all thru her life, hold on let me look it up on my smallville elementary skool the-sooras

    Reputation! And I don’ts appriciate it. I didn’t get my daddy to pay for my GED for nuthin.

  74. Haley R-A S

    Actually, I have yet to attend collage yet, but I actually understood everything (mathmatical equations and conversions withstanding, as they are my weak point) that was said in this forum, and while thats probably not very amazing in comparison to a supernova, learning a few things I didn’t know (mathmatical things mostly, I will admit) was equally amazing. I am left with a few questions in regards to our beautiful sun.

    For one thing it was stated that there is no way to tell when a supernova will happen, which makes me question how we know our sun will not be giving out within the next hundred years or has not already eight years and 33 seconds before you read this? Mainly I am more concerned about the former rather then the latter. As thats my main concern and I am sure when the question is answered my other questions will be inherently answered as well I will with hold the others until such a time as I am proven wrong and do have to ask for more information. While I humbly await the answer(s) to my pressing question I wish to thank you all in advance for answering.

  75. MadScientist

    I’m hoping it went Kablooie! about 600 years or so ago …

  76. Messier Tidy Upper

    Good write up BA. :-)

    Saw this issue last night on the Bad Astronomy Universe Today forum too :

    http://www.bautforum.com/showthread.php/104497-Betelgeuse-supernova-any-day-now-Or-is-it-a-hoax

    Folks wanting to find out more would also be well advised to check out the renowned stellar expert James Kaler’s Betelgeuse page :

    http://stars.astro.illinois.edu/sow/betelgeuse.html

    Which has lots more fascinating details including :

    We do not really know the star’s condition at the moment, but the odds are that it is now in the process of fusing helium into carbon and oxygen in its core. From theory, its initial mass should have fallen somewhere around 18 or 19 times that of the Sun. Starting life as hot, blue, class O star only around 10 million years ago, Betelgeuse will fuse elements through neon, magnesium, sodium, and silicon all the way to iron. The core will then collapse, causing the star to blow up as a supernova, most likely leaving a compact neutron star about the size of a small town behind. If it were to explode today, it would become as bright as a gibbous Moon, would cast strong shadows on the ground, and would be seen easily in full daylight.

    As I noted on the BAUT thread, I’d rather see Eta Carinae go supernova personally because

    1. Its circumolar and in the sky all the time form my home town (Adelaide, South Oz if you’re wondering.)

    2. Eta Carinae is an amazing superluminous hypergiant witha long and fascinating history – that has been followed closely but it is also a fairly faint and obscure star as seen from Earth’s skies whereas Betelgeux is tehtenth brightest and forms a major part of amajor constellation so ..

    3. When Betelgeux goes I’ll really miss it. ;-)

    I think we’re overdue for a bright supernova in the Milky Way aren’t we? ‘;-)
    (Yes I know, statistically it doesn’t work that way. But still.)

  77. Mark

    When I came across this “story”, my immediate reaction was “what does Phil Plait have to say about this?” Thanks for the rapid response :)

  78. Messier Tidy Upper

    Betelgeux, Betelgeuse, Alpha Orionis! There I’ve said its name thrice! ;-)

    Funnily enough we only recently found this M1 Ia red supergiant was a lot bigger and brighter and further away than we thought. Previous estimates of this Betelgeuse’s distance – & consequently size & brightness – had it at 430 light years away. Then a more recent study found it was much further away- giving us the 600 light year figure. Actually, 640 light years distant based on Betelgeux’s natural radio emissions with stellar expert Jim Kaler suggesting a compromise figure of 570 light years on the Kaler Betelgeuse page I’ve linked. (In moderation now, above)

    So far from shrinking in one sense it has became much bigger as we know it lately! ;-)

    Under that mistaken ’430 ly off’ idea, Betelgeuse was :

    - 650 times the Suns radius which meant the stars fuzzy outer atmospheric “surface” would have extended out to 2.8 AU or the middle of the asteroid belt.

    - 55,000 times as bright as our Sun giving it an Absolute (real brightness) Magnitude of minus five point one meaning that it would be brighter than Venus ever gets if it was located just over thirty light years away.

    - About 15 times as massive as our Sun.

    Source : Page 33, Kaler, James B., ‘The Hundred Greatest Stars’, Copernicus books, 2002.

    Now while the distance is still somewhat uncertain those already impressive figures have all increased quite substantially. :-)

  79. @AliCali (52.),

    “If the sun is out when Betelgeuse explodes, you’ll have two suns. But if it’s nighttime, then you’ll get a temporary, nighttime sun. Jeez, it’s so simple! This is why NASA launches solar-observing satellites in the daytime.”

    This is not quite true, because the time when a star is visible in the night-time sky depends on the earth’s orbit around the sun (once a year), not its rotation around its axis (once a day).

    Think about a line between the sun and Betelgeuse, like this:

    SUN ——————————– BETELGEUSE

    As it happens, the circle the earth makes around the sun can be drawn in the same picture, although it’s a bit difficult to do with text. Anyway, the position of the earth depends on the time of year, and that’s something I can draw with a little (e).

    In December it looks like this:

    SUN (e) —————————– BETELGEUSE

    In March:

    SUN ———————————- BETELGEUSE
    (e)

    Of course we’re still doing our day-and-night rotation, which I’m trying to show with the () around the (e).

    Today, in June, we are here:
    (e) SUN —————————— BETELGEUSE

    And if the supernova reached us today, we’d all be kinda bummed out. Because whereever you are on Earth, if you look in the direction where Betelgeuse is, the sun is in pretty much the same direction. So they’d appear in the sky at the same times, and as everyone else has pointed out, Betelgeuse won’t actually be anywhere near as bright as the sun. More like the crescent moon in daylight, at best. So you’d need to put your hand up and block the sunlight out of your eyes to see it faintly in the glare, or get a little telescope, or wait until sunset to see when it lags a little behind. If it happened at midday PST in June, only the astronomers in the US would notice, while us Aussies wouldn’t be able to see it yet – it’d be 3am for us, so we’d still be on the left hand ( of the (e). We’d have to wait until the Earth turned and the sun came up, and then we’d have exactly the same crappy view you guys do.

    No, I’m hanging out for the light to reach us in a December, when Orion is high in the sky at midnight. In my December picture, the sun is on one side of the (e), and Betelgeuse is on the opposite side. And if it starts at midday PST, I’ll be chuffed, because you guys will be facing the sun, while we’ll be facing kind of the right way, or at least we’ll still have Orion in the eastern sky. But I won’t laugh too hard, because you’ll only have to wait until sunset, and anyway it’ll be bright for 3 weeks and we’ll all have a decent look.

    Anyway the funny thing about the original post is that it said that ‘some folks’ would be in each of the two situations, which would imply that there are people on both sides of the sun. Now, last time I checked, there weren’t people on the other side of the sun from us. Not human people, anyway. (It’s a bit of a radio blackspot.) If the sun went round the earth every day, then everything I just wrote would be wrong … but sadly not.

    …. and then as I wrote this, eyelessgame explained it much more concisely in comment 73 :P Oh well!

  80. Harry’s right. I divided seconds by minutes instead of minutes by minutes. Point’s still valid though.

  81. Messier Tidy Upper

    @63. kebsis Says:

    Question; Theoretically, if Betelgeuse were to explode, would it leave a more or less permanent fixture in the sky? It would be amazing to be able to look up at the sky at night and see the remains of a super massive star with the naked eye.

    Betelegeux would make a bright supernovae for a few months perhaps longer and then it would gradually fade. Not sure of exact details but try comparing it with SN 1987 and scale up for the (much) closer distance given SN1987a was in the Large magellanic Cloud galaxy (163,000 light years away) and not about 600 ly away in our own arm of the Milky Way.

    When Betelgeux goes, it will certainly leave a bright new supernova remnant but I’m afraid I don’t know whether such a remant will be visible to our unaided eyes or not and I have to say I rather doubt it will be. It’ll be spectacular through a telescope – and binoculars too – I’ d reckon but seeing it without optical aid .. Hmm ..I’m not so sure.

    Anyone else want to do the math and enlighten us further please? (Afraid mathematics is my weak point. :-( )

    @ 32. Andy Fleming Says:

    Phil’s blown this one out of the water in his own effective style, so they’ll start looking for something else under 25 light years away. As nasty little things such as Chandrasekhar masses won’t bother them (why let science get in the way?) I’ll go with a Type Ia supernova from the detonation of white dwarf Sirius B… If only they could just accrete a little knowledge!

    Actually Procyon B – the littlest dogstar of all the stellar barking quartet* – would be the better candidate. Sure its 11 light years distant not 8 but Procyon A is currently evolving into a subgiant according to some schools of thought and I also think Procyon B is a bit more massive than the Pup Sirius B. (Thus, counter-intuitively, actually smaller in diameter – the extra mass squashes the white dwarf smaller btw.) So combine a more massive white dwarf with an evolving towards gianthood companion star which will possibly start losing matter which gets caught up by its white dwarf companion and then what does that lead to eventually .. Type Ia SN! ;-)

    Of course, the ‘eventually’ is the important bit – the timescale is very long and the distance between the Procyon pair is probably too great for them to interact and the masses too low for a supernova anyhow. (Procyon interestingly is the same mass as Mira – 1 and a half solar.) But still.

    I’ve read a quite reasonable SF novel – ‘Supernova’(Avon Books, 1991) by Roger MacBride Allen & Eric Kotani dealing with Sirius going supernova that I’d recommend.

    ———————————

    * The Stellar Barking quartet are :

    1. Sirius A – “the Dogstar”
    2. Sirius B – “the Pup”
    3. Procyon A – “The Little Dogstar”
    4. Procyon B – “thelittle Puppy.” ;-)

  82. Oh and Hi Haley! In answer to your question, scientists have studied stars similar to our sun and worked out that a star with the same mass, called type G (unlike Betelgeuse the massive red giant, type O) isn’t likely to go supernova at all. It will likely expand a lot at the end of its lifetime, though, and engulf the smaller planets (including us). As to when … well, our closest guess is based on its age, because while we can study our sun much more easily than Betelgeuse, we still don’t know absolutely everything going on inside. I believe estimates of the age of the solar system put the sun at about 4.6 billion years old, or about halfway through its lifespan, so we’ve a while still to go :)

  83. Messier Tidy Upper

    If these people are worried by the lack of roundness exhibited by Betelgeux we’d better NOT tell them about the wonderful Omicron Ceti A known to its friends as Mira! ;-)

    http://en.wikipedia.org/wiki/Mira

    Or the other similarly distorted class of Mira (long period variable) giants for that matter. ;-)

    (Yes *I* know the Mira stars don’t have enough mass to go supernova but will those mob?)

  84. John Paradox

    53. Jason B Says:

    Oh but wouldn’t it be cool to see? Explodey stuff is always awesome … Dr P, is there anything we can do to speed up the process :)

    Anybody contacted The Mythbusters about this yet? ;)

    78. Richard Says:
    June 1st, 2010 at 9:55 pm

    What we should be concerned about is the effects of life on Earth after Phil’s “eardrums explode outward in every direction at the speed of light”. That’s not a world I want to live in! :-)
    Imagine the Cherenkov Radiation!!!

    J/P=?

  85. CoryG

    That eardrum explosion at the speed of light is the gravity wave of the supernova preceding the light and gamma rays, not skepticism.

  86. ggremlin

    Well, at least it isn’t on Orion’s belt, then we would be in real trouble. Here kitty, kitty. :)

    But seriously, why is there a 25% plus or minus probability in the distance from us? Still outside the danger zone but I’m curious

  87. Navneeth

    Probably, all we’ll get is visible light (not gamma rays or X-rays), so it shouldn’t be an ELE. It’s sure gonna freak everyone out, though…..

    Then it will form a black hole, but we’re too far away for that to matter.

    [emphasis mine]

    I’m actually surprised to see such statements in a doomsday rumour.

  88. Mike

    Classic Bad Astronomy. :D

  89. Zaragatunga

    “A supernova has to be no farther than about 25 light years away to be able to fry us with light or anything else, and Betelgeuse is 25 times that distance (which means its power to hurt us is weakened by over 600x)”

    According to Wikipedia (http://en.wikipedia.org/wiki/Gamma-ray_burst#Rates_and_impacts_on_life), a Gamma-ray Burst (which could be caused by the collapse of a very massive star like Betelgeuse) would impact life on earth and possibly cause an Extinction-Level Event up to 1 kiloparsec away (that’s 3260 light-years), so Betelgeuse, which is between 335 and 519 light-years away, could very well be damaging to the Earth’s biosphere.

  90. Buzz Parsec

    Everyone’s pretty much demolished the DST and the “some people will see it in the daytime and others at night” Bad Astronomy… Do we have a score on this yet? At least 6 points, not bad for 4 paragraphs.

    What’s an ELE? End of Life on Earth? Do these people actually have an acronym for that?

    #70, Alphaniner – that farm boy wouldn’t be named Luke by any chance? LOL

    #90, ggremlin – we all know (unless our memory’s been zapped) that Orion’s belt was last seen in Flushing, NY (wrapped around Orion’s neck), so that would be a little close for comfort.

    Oh, and the obligatory “Phil, why are you posting about Bad Astronomy? Don’t you know this blog is supposed to be about religion/politics/medicine/cute animals/…? How dare you!”

  91. Better late than never

    I have to say: This has been fun!

  92. Hitler

    Hitler is not happy ..

  93. Michel

    Dear Phil.
    Can we at least get a list from you of stars that WILL go boom soon?
    Please.

  94. You’re slackin, Phil. Let me help.

    Forget “the essay”, buy the frakin BOOK: http://www.amazon.com/Death-Skies-These-Ways-World/dp/0670019976

    Your welcome ;-)

  95. g4r

    (quoting the original post)
    well, oddly enough my skeptic alarm bell in my head rings loudly enough that my eardrums explode outward in every direction at the speed of light.
    (/quote)

    @Phil: have you tried reading some more posts of the same author, even in the same thread ?
    I did, and my own (patented!) skeptic detector quickly reached the “you’ve better things to do with your time” level.
    And now there’re some blogs claiming that this blog asserts that Big B is going nova tonight. Oh boy…

    Still, most of the responses here are well-thought and interesting.
    So there’s still hope for humanity.
    I guess…

  96. I wish the rumor was true. I would liked to have seen it.

  97. Peter

    I wish the rumor were true.

    I’d like to witness a nearby, relatively speaking, supernova in my lifetime. One that one can see during daytime with the naked eye. How long ago has it been that such a thing went off? November 1572, October 1604. Two in a single person’s lifetime. And we are let to wait for over FOUR CENTURIES. That’s just not fair.

    I would miss Orion, with such a wound the most beautiful constellation would never be the same.

    I would miss my favorite star, glowing warmly end gently in the night’s sky.

    But, damn, would I enjoy viewing such a cosmic spectacle.

  98. LPGraham

    I’m sure someone has already addressed this but here goes…

    If it went supernova today, “we” wouldn’t know it for 600 years, so who cares?

  99. while you’re all outside being blinded by the supernova fragments, I’ll be stocking up on weedkiller and salt water tanks.

    Damn triffids ain’t getting me, no sir.

  100. Timmy

    I need to put a new roof on my house, but maybe I will wait until Beetlejuice explodes next week. Then I can claim supernova damage on my insurance policy. Thanks for the heads up, Phil!

  101. Edgar

    UC Berkeley physicist Charles Townes. You are right this was a year ago. Still, it isn’t getting any larger.

  102. ELE = Extinction Level Event as far as i know

  103. @Gray (No.12): Yes, that’s pretty much it. The light from Betelgeuse takes 600 years to reach us, so any event we can see from Earth happened 600 years ago. That speed of light limit counts for any kind of radiation, too – so X-rays, ultraviolet, and anything else would take at least 600 years to reach us.

  104. Adrian

    Why is everyone saying Orion would lose his shoulder? If anything, he’d get a bigger shoulder for a while. Then maybe we could rename him Trogdor!

    That’d be ace….

  105. Mike

    Matt, the answer to your question is yes, if we see the supernova today that means that it went supernova 600 years ago.

  106. A large star 600 light years away is ready about to go supernova, and scientists predict this will be an ELE. Earthlings scramble and build huge spacecrafts, take two of each species, and a few rich folks, and get far, far away from earth as time runs out. Looks like Roland Emmerich (2012 & The Day After Tomorrow) has the basic plot for his new movie ;)

  107. a different phil

    To me, it was all over when I read “The extra hour of light from daylight savings time won’t burn the crops, but this might.”. Evidently the guy thinks that switching to daylight saving time actually produces an extra hour of light from somewhere, as opposed to just moving the existing amount of daylight to a different position on the clock. Anybody who’s got that firm a grasp on the idea of time can pretty much be counted on to get everything else sciency wrong.

  108. I would just like to say that the comments here are awesome. Seriously. This is real dialog with back and forth and real SCIENCE. I’m learning a lot. I thought you should know that.

    Thanks!

    HJ

  109. AliCali

    @85 theangeljean

    I was wondering if anyone would take me seriously. I was hoping the line, “This is why NASA launches solar-observing satellites in the daytime,” would be the clue that I was kidding.

    Still, that was a nice explanation. I like the diagram (e)—-SUN. Very imaginative when you can only use text to make a point.

    In Australia, Orion is upside-down, right? This just proves that the northern hemisphere is the ‘correct’ hemisphere, since the constellations are right-side up.

    This reminds me of a Dave Barry line. He said that non-US countries use the “foreign” (aka “metric”) system, whereas we use the “American” (aka “correct”) system.

  110. Ok…it seems this is gonna be the next hoax, “updating” the old Mars Hoax.

    :: Preparing to write about it… ::

    @AliCali: There is no such thing as “correct” hemisphere. Think of poor Cassiopea when she shifts from M to W :-p

    Plus, in space… UP and DOWN, LEFT and RIGHT are nonsense.

    Clear and dark skies!

  111. AliCali

    @ Julio Vannini

    ” There is no such thing as “correct” hemisphere. Think of poor Cassiopea when she shifts from M to W :-p”

    Ah, but what would Australians say about Cassiopea? Ah! They can’t even see it! More proof that we are the ‘correct’ hemisphere.

  112. alfaniner

    Would it be safe to look at (up to a point)? I imagine some “Day of the Triffids” scenario where everyone who looked at it ends up blind. ;-)

  113. Tim G

    We should have a supernova in our galaxy on average about one a century, right? The last one visible to the naked eye (in 1987) occurred in a Magellanic Cloud 168,000 ly away. So one ten times brighter than that in my lifetime is a reasonable possibility.

    Of course, Betelgeuse is at a distance much closer than the median distance to a candidate star in the Milky Way. Being at 7.5° above the celestial equator is just about the ideal declination considering the distribution of the world population. However, if it blows around the (Northern) summer solstice, that would suck IMO because the sun would be too close for good nighttime viewing.

  114. JGlanton

    Fascinating and informative article, Phil. About once per month someone at work will bring up some astronomical phenomenon or conspiracy and bring it to me because they know that I am an (amateur) astronomer and space imaging technology developer. I eventually get tired of answering the questions and researching some basic facts that they could have done themselves. So next time someone tells me that Mars has gotten bigger or the earth will end in 2012, I am going to dump them on you. You do a public service.

    I should have sent them right here when they asked if the LHC was going to make a black hole.

  115. Chris Winter

    Thanks, Christian Ott (#66), for clearing that up. I had thought that no one on this planet had the knowledge to predict a supernova explosion so precisely. But I left open the possibility there was some recent breakthrough in stellar-core theory.

    So I can go back to pointing out that such abilities belong only to the Moties (of The Mote in God’s Eye) and perhaps the Asgard.

    Somewhat OT: IIRC, this was one of the prominent nearby stars the starship Enterprise never visited. Maybe because its name is not euphonious?

  116. RAF

    I’ve always looked to the sky in the hope that Betelgeuse would (over the course of a couple of hours) get brighter, and brighter, and brighter.

    I can’t think of a more amazing sight to behold…but alas, it likely won’t happen in any of our lifetimes.

  117. @AliCali

    LOL, true. but u cant see “The Fly”
    :)

  118. Gus Snarp

    Wait a second, is that diagram saying that Betelgeuse is bigger than Jupiter’s orbit? Like if it were sitting where the sun is it would engulf Jupiter? Cause that’s really big.

  119. Doug

    RAF, Who’s to say it won’t happen in our lifetimes? The star has shrunk in size by 15% in the past 2 decades. The suggestion seems to be that this could be relatd to it nearing the end of one of its fusion cycles. It could also be that it’s just normal for it to expand and contract over decades for some unknown reason. If it’s not a cyclical thing and it is losing one percent of its diameter a year, that cannot continue for too many more years before something has to happen. If it’s contracting because it’s consumed its helium then we’re never going to live to see the boom. If it’s contracting because it’s out of neon, then we’re going to see something and in the very near future. I hope to see it blow in my lifetime.

    As to the original post that started this all, it seems to me upon reflection that since the telescopes at Mauna Kea are (all but one) optical, and Orion is right under the sun right now, they can’t have noticed it shrinking in the past few weeks because they couldn’t have seen it at all through the daytime sky.

  120. Arthur

    So, we can measure the expected lifetime of stars on the main sequence, and we can estimate their current age, which should mean that we can estimate when they will leave the main sequence. Is there anything similar for stars that have already left the main sequence? Can we estimate when a red giant will go supernova? Or is this a complete unknown?

  121. Messier Tidy Upper

    @121. AliCali Says:

    In Australia, Orion is upside-down, right? This just proves that the northern hemisphere is the ‘correct’ hemisphere, since the constellations are right-side up.

    No *we* Aussies & Kiwis see constellations the *right* way up – you Americans are the one’s who see them upside down! ;-) :-P

    This reminds me of a Dave Barry line. He said that non-US countries use the “foreign” (aka “metric”) system, whereas we use the “American” (aka “correct”) system.

    No, its the imperial or “American” system that’s the foreign one – at least it is where I’m from! ;-) :-P

    @ 123. AliCali (again) :

    Ah, but what would Australians say about Cassiopea? Ah! They can’t even see it! More proof that we are the ‘correct’ hemisphere.

    Yes but can you Northerners see the Southern Cross, the “pointers” Alpha and Beta Centauri, the Magellanic Clouds, Omega Centauri, 47 Tucanae, the “False Cross”, Canopus and Achernar among many other things? No? I think we southerners win! ;-)

    BTW. Did you know the top three brightest stars are located in the southern half of the sky -and several of the top 30 are so far south – Alpha Centauri, Achernar, Alpha Crucis, Mimosa etc .. that they can only be seen from the southern hemisphere? Plus we get the best views of Scorpius and Sagittarius so, yes, we southern hemispherers definitely win! (Not to rub it in or anything!) :-P

  122. Messier Tidy Upper

    @131. Arthur Says:

    So, we can measure the expected lifetime of stars on the main sequence, and we can estimate their current age, which should mean that we can estimate when they will leave the main sequence. Is there anything similar for stars that have already left the main sequence? Can we estimate when a red giant will go supernova? Or is this a complete unknown?

    We can’t be too precise but we can roughly estimate how long a star has before going supernova from :

    - calculating its mass and age then working out how long it should live from stellar theory,

    - from hints obtained via spectroscopic obbservations which provide clues such as anomalous elements indicating core burning eg. Nitrogen for Eta Carinae

    &

    - by past stellar history of individual stars outbursts and shells of ejected material, eg. Eta Carinae again & Sherman __?? (Numerals – 25 – I think. Its one the BA has studied & similar to the precursor blue supergiant that exploded as SN1987A if I remember rightly.)

    We’re still learning heaps more and a few more examples of supernova precursors and how stars behave just before they go ka-boom such as, maybe, Betelgeuse and Eta Carinae will help us learn more incl. how to make more accurate predictions from past precedents.

    I do know there are some lists of possible candidate supernova of varying classes and natures such as Wolf Rayet (WR) 104, some red supergiants and white dwarfs and even some blue supergiants such as the one that produced SN1987 A in the LMC.

    Of course, we won’t know exactly how accurate such lists are until we find some of the stars on these lists actually detonating and that may take a very long time! But we’re working on it. ;-)

  123. alHiboux

    Only one H2G2 reference in the comments? Shame on you, people!

    But yeah, a source, thrice removed, nothing published or to be published… clearly it´s true, and the government is hiding something!

  124. JMW

    I herewith petition that the name of the star be changed to “Betel”. Once it explodes, the ejecta can then be named “Betelgeuse”.

  125. Messier Tidy Upper

    @ 130. Gus Snarp Says:

    Wait a second, is that diagram saying that Betelgeuse is bigger than Jupiter’s orbit? Like if it were sitting where the sun is it would engulf Jupiter? Cause that’s really big.

    See one of my all-time favourite BA blog posts for a videoclip that puts everything into perspective from our Moon to VY Canis Majoris – the largest known star. This is *very* well worth watching.

    Betelgeux is equivalent (roughly) to the size of Antares A in that. :-)

    http://blogs.discovermagazine.com/badastronomy/2009/06/12/scale/

    Also see this table I compiled for an article ages ago :

    Table I : How super is the giant?
    Compiled by Steven C. Raine from the sources listed.

    This table compares the 10 stars – five giants, 1 to 2 bright giant and 3-4 supergiants with Canopus being right on the bright giant-supergiant boarder. The comparison includes the nearest and apparently brightest of each class and also the famous “wonderful” variable Mira which gives its name to a whole class of variables and the largest known star VV Cephei. Incidentally, Pollux has a confirmed exoplanet orbiting it and Aldebaran also has a suspected planetary mass companion.

    Star Spectral class & Type Distance Mass Radius Extends to Notes

    Pollux K0 III Orange giant 34 1.8 10 1/8th the way to Mercury Nearest giant
    Aldebaran K5 III Orange giant 60 2.5 40 1/2 way to Mercury Near Hyades
    Arcturus K1 III Orange giant 37 1.5 26 1/4 of the way to Mercury Brightest giant
    GaCrux M3 III Red giant 88 3 113 Over 1/2 way to Earth Closest Red Giant
    Mira M7 III Red giant 420 1.5 500 Between Mars & Jupiter Famed variable

    Scheat M2 II Bright red giant 200 95 70% the way to Venus Bright giant

    Canopus F0 II- Ib White Supergiant 313 8-9 65 75% the way to Mercury Nearest supergiant

    Antares M1.5 Ia Red Supergiant 600 20 800 3/ 4ths the way to Jupiter Nearest red s’giant
    Betelgeux M1 Ia Red S’giant 640 20 950 About Jupiter’s orbit Brightest reds’giant
    VV Cephei M2 Ia Red S’giant 2,000 25-40 16-1,900 85% the way to Saturn Largest star

    Hope that’s helpful & interesting for you! :-)
    Notes : Radius & luminosity measured relative to our Sun, (ie Sun =1) luminosity is bolometric meaning it includes all wavelengths. Distances are in light years.

    s’giant = supergiant, Ia = Bright Supergiant, Ib = Less bright supergiant,
    II =Bright giant, III =giant.

    Brightest is in terms of apparent magnitude NOT absolute magnitude; eg. VV Cephei is actually brighter than Betelguex but is further away & thus seems dimmer. Canopus is the brightest supergiant & second brightest star overall in our skies in apparent magnitude yet other stars are much brighter intrinsically eg. Eta Carinae which is 4 to 5 million times brighter than our Sun!

    ‘Extends to’ = where the star’s surface would be if the star replaced our Sun, note the diffuse “edges“of red giants and supergiants make this aspect hard to estimate accurately with infra-red, visual and other measures sometimes giving differing results – & further complicating this some of these giants and supergiants actually pulsate and change physical sizes!

    A recent study determined that Betelgeux is actually much further than earlier thought – 640 rather than 400 light years & thus also must be correspondingly larger than previously judged – the figures used here are the latest ones.

  126. Tyler Durden

    In regards to the “If it blew up 500 years ago, we still wouldn’t know now” – I’d just like to make a caution to any possible FTL travelers in the future:

    *Always* send a probe first… what seems like a nice place to visit when you peer through a telescope may in fact be a solar-system sized ball of plasma, the light informing you of that fact just hasn’t reached us yet..

  127. Messier Tidy Upper

    Arrgh! Out of editing time to tidy up that copy’n'paste job. That’s supposed to be :

    ***

    Key : s’giant = supergiant, Ia = bright supergiant, Ib = Less bright supergiant,
    II =bright giant, III =giant.

    Notes :
    Radius measured relative to our Sun, (ie Sun =1)
    Distances are in light years.

    Brightest is in terms of apparent magnitude NOT absolute magnitude; eg. VV Cephei is actually brighter than Betelguex but is further away & thus seems dimmer. Canopus is the brightest supergiant & second brightest star overall in our skies in apparent magnitude yet other stars are much brighter intrinsically, eg. Eta Carinae which is 4 to 5 million times brighter than our Sun!

    ‘Extends to’ = where the star’s surface would be if the star replaced our Sun, note the diffuse “edges“of red giants and supergiants make this aspect hard to estimate accurately with infra-red, visual and other measures sometimes giving differing results – & further complicating this some of these giants and supergiants actually pulsate and change physical sizes!

    A recent study determined that Betelgeux is actually much further than earlier thought – 640 rather than 400 light years & thus also must be correspondingly larger than previously judged – the figures used here are the latest ones.

    Hope that’s helpful & interesting for you! :-)

    ***

    This should all make sense once my earlier comment comes out of moderation assuming it does (Which there’s no reason not to. Just had a link )

    The article I compiled that table for actually comes from a discussion in another BA blog topic which considered the differences between giants and supergiants which started here :

    http://blogs.discovermagazine.com/badastronomy/2009/02/18/wonder-twins-telescope-sees-stars-dying-gasps/

    Odd thing is I’m still not sure the person I answered the question for (#15. SLC there) ever saw what I wrote based on him asking! Which turned out to be a whole article for my astronomical societies monthly newsletter. ;-)

  128. Someone way up the log here said that there wouldn’t be any net effect on gravitational observations. Now, someone please correct me, but since the star does convert mass into energy, it follows in my mind that the supernova explosion would quickly convert a measurable percentage of the stars mass into energy, which it will generally shed in an isotopic manner. Some of this energy will go to make the heavier elements of course, but the net mass of the star should go down according to my feeble & 75 YO wet ram.

    So it seems that with so much mass going into energy in such a short time scale, the net effect should be a small but measurable reduction in its gravitational pull. LIGO is looking for such an event, and just like the neutrino thing, it seems to me to be a quite handy way to prove once and for all, that the speed of gravity is either instant (some orbital mechanics fall apart if it is not) or at C speed. If the latter, then the LIGO results would show the wiggle at the instant of the collapse.

    And in the case where gravity is instant over distance, we would likely never correlate the visible event with the LIGO spike since they would be nominally 600 years apart in time. And that would throw a huge pipe wrench into the gears of relativity, possibly making MOND a better idea.

    Its an interesting conundrum. In any event, we would learn 100,000 times as much as we now know about supernova’s just because its in our far pasture, and not halfway across the visible universe. And I, like the majority here, certainly hope it happens within my remaining lifetime. Like Halley, that would certainly put a period on what has been a most interesting life for the last 75 years.


    Cheers, Gene

  129. Gus Snarp

    @Messier Tidy Upper – So that’s a yes then? Thanks for that. It’s really quite stunning how big the universe and the things in it are. I really like this image for size comparisons, it seems to help me grasp things better than video: http://commons.wikimedia.org/wiki/File:Star-sizes.jpg Even at that I never really thought about these stars exceeding the orbit of Jupiter. The orbit comparison is a nice one. I’m still not sure that our heads can really comprehend things at that scale though.

  130. Mister Fibuli

    Damn. Hopefully it goes soon, though, because it would seriously make my week to see something like that.

  131. John G.

    But Captain, she’s gonna blow.

  132. Keith (the first one)

    Thanks Greg Fish (19), though I don’t actually understand most of that. I’ll take it as a no.

    BTW, 141 posts and no one has even joked about what the astrologers will do when Orion is missing a star. I bet they won’t even be able to agree on whether it would affect their horoscopes not. lol

    I predict there will be various groups mourning it’s disappearance (visible to the naked eye) with at least one blaming it on human activity in some way.

  133. Messier Tidy Upper

    @144. Gus Snarp Says:

    @Messier Tidy Upper – So that’s a yes then? Thanks for that.

    Definitely a “yes” – although size (like so much else) is relative. ;-)

    My pleasure. :-)

    In fact I’ll even tidy up de-clutter & simplify the comparison table there to :

    Star Type Radius Extends to

    Pollux Orange giant 10 1/8th the way to Mercury
    Arcturus Orange giant 26 1/4 of the way to Mercury
    Aldebaran Orange giant 40 1/2 way to Mercury

    GaCrux Red giant 113 Over 1/2 way to Earth
    Mira Red giant 500 Between Mars & Jupiter

    Scheat Bright red giant 95 70% the way to Venus

    Canopus White Supergiant* 65 75% the way to Mercury

    Antares Red Supergiant 800 3/ 4ths the way to Jupiter
    Betelgeux Red Supergiant 950 About Jupiter’s orbit
    VV Cephei Red Supergiant 1,600-1,900 85% the way to Saturn

    * Canopus has been variously termed a bright giant or supergiant depending on source – and I’ve seen it listed as spectral type A9 as well as its more usual classification of spectral class F0. Not sure if the star has changed type or been reclassified recently.

    ——–

    To make things hopefully neater and clearer & because I never fail to be amazed and just plain love considering the superlative variety of stars. :-)

    I also wanted to note that the “listed sources” I used to compile that table were from James Kaler’s Stars website & book – too many links to include here but I’m happy to provide them separately via email to anyone who wants them or maybe via the BAUT forum (I’m StevoR there) if anyone’s seriously interested. :-)

    ****

    PS. D’oh – that’s intended to be spaced out more to look better – it is in the edit view here. But not as it turns up once submitted. @#$@!@$$%^^&^^$ computers. Sigh.

  134. Pi-needles

    After such a good debunking of this dodgy ‘Betelgeuse is going supernova any second now!’ claim by the Bad Astronomer, it sure would be ironic if Alpha Orionis *did* blow up in our skies tonight or tomorrow night wouldn’t it? ;-)

  135. Another Adam

    @39 Old Rockin’ Dave – Crop rotation, HAH. Funniest thing I heard all day. Closely followed by JMW @ 138.

    When it does blow the story will change to Orion was gored by Taurus.

  136. What kind of stars *do* cause a gamma ray burst?

  137. Simon

    Klopfer: “Shows a complete failure to understand.”

    Fixed that for you. :-)

  138. Oli

    Damn. I was looking forward to a supernova.

  139. Tony Stein

    For the person way up there who wanted to calculate how far away Betelgeuse is from Earth compared to the sun, you can try this trick. Just type:

    convert 600 light-years to AU

    into your google bar. The convert function is lots of fun.

  140. Levi in NY

    I’m still holding out hope the old bugger will blow in my lifetime.

  141. Eric Legge

    The star is 520 light years away, so its light takes 520 years to reach us, so what we see of it happened 520 years ago. There is no way we can see what state it is currently in because nothing can exceed the speed of light.

  142. Bruce

    Those of you worried that Orion “will lose his shoulder” can relax; Betelgeuse is Arabic for “armpit.”

  143. RockDoctor

    @Messier Tidier Upper
    “Nitrogen for Eta Carinae ”
    I’ve long harboured a (not very) secret desire to see Eta Carinae “go”. But if it’s still burning nitrogen … that’s a good while to wait yet. Maybe I won’t see it in my lifetime then.

    Oh well ; I’ll have to hope for some other star to go “pop”.

  144. In case any one’s wondering, I calculate that a supernova would have to be 400 AU (note: NOT light-years) or closer to be as bright as the sun (the sun is mag. -26.7. A type Ia supernova has an absolute magnitude of -19.3). Needless to say, no stars other than the sun are that close.

    Betelguese will probably explode as a type II supernova, though, which are dimmer (I think).

  145. reidh

    love to live to see. Too bad sirius et al can’t do that.

  146. Jason

    Orion was the first constellation I learned. The nebula and the great red giant Betelgeuse hold a special place in my love of astronomy.

    But I still hope it explodes sometime soon.

  147. Astro

    interesting read but i was really annoyed with your constant use of exclamation marks! <= see? this is a scientific issue written in an emotional manner.

    also its quite an ego you got to definitely determine it wont have any effect on ALL of the solar system. our planet is an insignificant spec in space, so imagine what we are. lets not pretend we know how space works, lets keep our feet on the ground, literally.

  148. Jesper

    Ok, ofcourse it’s only a rumour based on nothing.

    But it would be incredibly COOL if it happened! ;)

  149. James Hawk III

    @Astro – You have a problem with science? Nothing Phil says is at odds with anything another astronomer would say (with the possible exception of the gamma-ray burst issue, but given the overall accuracy of Wikipedia, I’m going with Phil on that).

    Also, just to clear up one little misconception: our planet may be small, but it isn’t insignificant–we’re on it. That makes it mightily significant.

    At this point I’d usually segue into a detailed criticism of your spelling, punctuation, and grammar, but people tell me that’s rude, so you’re off the hook today.

  150. Have most people missed the obvious flaw in this story.
    As light takes approx the same amount of time to reach Hubble ST as it does to reach earth. Any so called observations that BG was no longer there when it is still visible in the constellation orion are just ludicrous.
    Doomsday prophets eh .. anyone remember the millennium bug?

  151. ed in az

    for all we know she blew 599 years ago. .. Well, the Mayans and ancient Egyptians had all this insight. . .. based on. … looking up at the night sky and making up myths that explained their observations…

    “ancient wisdom” is a contradiction in terms

  152. Charlotte

    Could someone please point out to these geniuses that the word is pronounced “BAY-tehl-jooze”? PLEASE? If I see one more “Beetlejuice” joke, I’m going to slit my own wrists.

  153. fluffycarrot

    awww, i was all excited for a minute there! i hope we do see a explosion this winter that would be a once in a life time event.
    although orion loosing his shoulder may be a bit sad i’m sure he find some way to protect our skys.(maybe trade his bow in for a tazer?)
    also is it true that a star like betelgeuse would burn diffrent elements in shells and only the inner portion of the core would actually turn to iron? the outer layers of the core being made of prgressivly lighter elements ? or have i understood that bit wrong?
    great comments btw made me lol.

  154. Mack

    Darn Sand worms!!

  155. Jenn

    I would just like to point out that this article is based around an anonymous poster who actually said, “The extra hour of light from daylight savings time won’t burn the crops, but this might.” Are people really this stupid?

  156. Wendy

    I know it’s been commented on already, but he lost me at “The extra hour of light from daylight savings time…” HAH!!!

  157. Anchor

    Shucks…Betelgeuse, as long as it’s been a red supergiant (probably over most of the history of homo sapiens on Earth) has NEVER been round. Convective activity ensures it is other than round.

    Red supergiants are squirrely like that.

    Not to worry, as Phil says. The blast would NOT much affect our planet. Oh, it might deliver a brief pulse of high-energy particles that temporarily knocks down the ozone layer, but it wouldn’t ruin our day any more than any of the other roughly estimated 1000 supernovae that have probably exploded within a few thousand light-years of the Solar System over our planet’s 4.5 BILLION-year history. That’s 4500 millions of years worth of time which our Solar System has wandered amongst the stars in the galaxy, and moved through the relatively perilous star-forming spiral arms – where the risk of relatively nearby and frequent supernovae is elevated over the average rate and proximity – for at least 20% of the time over that vast period.

    The biggest effect of Betelguese going off would be that people will briefly – over the course of several months – marvel over an exceptionally bright star in the sky that would be visible even in horribly light-polluted places like Mexico City and Hong Kong, an apparition that would be somewhere between 100 to 1000 times as bright as Venus. That kind of brilliance compressed into a single naked-eye point-source would definitely call attention to itself, but it would barely match the luminosity of a full moon, which most people never bother to look twice at.

    However, whenever it does go off (and it most likely will at some point, if we are still around to witness it) the worst it can do is render our beloved constellation of Orion without a shoulder. Boo hoo. (Now THAT could set the astrological sort into a panic). The rationally scientific and optimistic side would know that in its place will be a fine telescopic supernova remnant that will last for at least the following few thousand years…plus a fantastic ring-side seat for studying the birth of a neutron star/pulsar at such relatively close range.

  158. AliCali

    Wow, over 180 comments on a topic that has nothing to do with evolution, religion, global warming, politics, gay rights, etc. There’s not even an obvious Troll (my previous smart-ass comments aside).

    @ 182 Anchor: “Not to worry, as Phil says. The blast would NOT much affect our planet. Oh, it might deliver a brief pulse of high-energy particles that temporarily knocks down the ozone layer, but it wouldn’t ruin our day any more than any of the other roughly estimated 1000 supernovae that have probably exploded within a few thousand light-years of the Solar System over our planet’s 4.5 BILLION-year history. That’s 4500 millions of years worth of time which our Solar System has wandered amongst the stars in the galaxy, and moved through the relatively perilous star-forming spiral arms – where the risk of relatively nearby and frequent supernovae is elevated over the average rate and proximity – for at least 20% of the time over that vast period.”

    I recall that there were hypotheses that nearby supernovas (supernovaes? supernovaii?) from the past contributed or caused minor extinctions. I know that the asteriod impacts had a much more severe extinction result, but I remember geologists perhaps detecting supernova material in the rocks at the same level of minor extinctions. How they figured supernova material, I cannot remember. I have a book somewhere about the geologist who found the K-T impact in Mexico, and he was going by the supernova theory before he found more evidence for asteroid impacts. I think his dad was pursuing the supernova-causes-extinction line. I think I’m rambling now.

    Anyway, although Orion’s shoulder or armpit (or Michael Keaton’s character) would be too far away, I wonder if in the past 4.5B years, there were closer ones or ones pointed our way with a Gamma-Ray Burst that did affect Earth more than a bright light.

  159. Tomas

    Okay, right, I may have told a girl that a big nearby star was about to blow up to try to get in her pants. I didn’t expect the rumor to get this big, sorry about that!

  160. Muskie

    Quick note for you, Haley: We’re 8 Light _minutes_ and 33 seconds away from the sun, not 8 Light years. We know quite a bit about our particular little ball of gas in the centre of our solar system (give or take a few hundred thousand miles, lol).

    Our sun is relatively young, and still has a couple billion years in it left before petering out, as it has nowhere near the mass enough to actually go supernova (though it’ll definately fry our little ball of rock from expansion.. but again, that’s in a few BILLION years. and we’ll be well out of there by then, we hope! :P ) I’d reccommend reading Phil’s book “Death From the Skies!” for more information about the ACTUAL cosmological threats that the planet actually faces. (of which basically all you won’t see in your lifetime. or that of your Great^276 grandchildren’s.)

  161. Gill Avila

    By the time we see it blow it will be old news—like about 520 years old.

  162. JCJ

    @121 AliCali

    The problem is, on this internet a statement like “The extra hour of light from daylight savings time won’t burn the crops, but this might.” is taken seriously by far too many people. Adding an absurd comment about NASA doesn’t make it clear whether you’re joking or just drank the Kool-Aid. :- ) I decided you were joking, but only after reading your post several times.

  163. JCJ

    On another note, since it has come up repeatedly here, I don’t know if the people perpetuating this rumor know the difference, but I’m sure Dr Plait does. Still, when I first discovered this blog I was disturbed and sometimes confused by the way he referred astronomical events “happening” at certain times, as in ‘the star went supernova in 1994′ (not an exact quote) when my science teachers 25 years ago were always careful to distinguish when an event occurred as opposed to when it was observed on earth. I guess for astronomers this distinction goes without saying.

  164. ah

    Ahem, it is possible that you got your tense wrong

    It may be, did Betelgeuse already explode…hence light travel, fun to think about. =]

  165. Slicer

    Gene, you’re wrong. The process of fusing elements heavier than iron actually TAKES energy and converts it into MATTER (!). This quick net energy depletion is why it implodes, and the implosion causes an explosion, sending a lot of that star’s mass (including lots of those precious heavy elements that were just fused) out of its gravitational field.

  166. Lunaloba

    Ali Cali – I love you!!! You are so funny!!! Let’s move to Betelgeuse and have little alien children!!

    Seriously folks, my father, a PhD enginerd extraordinaire calls me tonight to tell me to go outside at 10 pm to see the supernova. I thought this seemed highly unlikely, but I must admit I was pretty excited!!! Like dancing around my house excited then I thought I should check it out and now I’m so sad :-(

    I was kinda bummed that Orion would never be the same, the poor shoulderless bastard, so there is a bright side.

    So let’s all start a petition to get our very own supernova in our lifetimes!! And if one of my friends (they all know I love astronomy even though I’m a GIRL) tells me that Mars is going to be the size of the full moon again I might just go supernova my own self!!!

  167. nedfumpkin

    Since it is 600 light years away, that means that when it does happen, it will have happened 600 years previously because that’s how long it will take for the light of it to reach us. That’s so cool since we are trying to determine is it has happened or not, not when it will happen.

  168. Redsplinter

    I knew it’d be safe. Relatively. As in suntanning is relatively safe.

    But I want to see the bonanza. Read the resulting poems. Laugh at the doomsday preachers.

  169. Redsplinter

    BTW, the part in the article about Betelgeuse being noncircular is correct: it means nothing.

    What would be important is if the average diameter is shrinking, which would show that the core is undergoing elemental change. Even then, however, that change does not mean that a nova is coming, unless the core has already progressed past the fusion into iron.

    I want to see it, and tbh I think it’s a sin not to be checking on it with some ‘scopes regularly, but it’s a let down to hope, all in all.

    It has, however, most likely happened. 640 light years or so. … I am putting cryostasis in my will

  170. Matt R Erickson

    I love crack-pot theorists…I really do there the ones who can sleep till noon and still figure out a way to get an A on math…LOL!

  171. BB

    Betelgeuse may have already exploded, Remember it is over 600 light years away. That means if it exploded 600 years ago the light would reach us today, if it exploded tonight, we would have to wait 600 years to see it. One thing is for sure, if it hasnt exploded yet it is definitely in its last years and too far to have any major effect on earth

  172. BB

    if you want betelgeuse to explode just say his name 3 times:

    Betelgeuse! Betelgeuse! Betelgeuse!

  173. Jonny

    The gods are angry!!! Sacrifice something QUICK!!

    But seriously it’s remarkable how such a conventional cosmic event has dramatically shaped human history over and over again.

  174. ScienceStudent

    Hmmm, so if Betelgeuse has already gone supernova and we get to see it sometime soon, doesn’t that mean all that scary explosion blackhole thing has already been sat there for 600 years and we really aren’t going to be affected? Ignorant apocolipse stories crack me up.

  175. Gort

    OMG! If a person named SCIENCESTUDENT cannot write nor spell any better than he/she did then weep for our future!

  176. Luke

    But how do scientists know for sure if it hasn’t already popped? The light and evidence of that happening would take 600 years to get to earth anyway… And plus, looking at Betelgeuse in the night sky today is looking at history… That light has taken 600 years to get here, so no one can say whether Betelgeuse has or hasn’t exploded, right?

  177. Luke

    If, once Betelgeuse has exploded, it forms a black hole, surely the constellation of Orion will be distorted and disfigured, maybe even some stars would be sucked in…

  178. Kieran

    @Luke
    P208: There is NO way of knowing wether its already gone supernova on our arse, nothing can travel faster than the speed of light (Unless your talking about the realms of quantum entanglement, which is, thankfully, irrelevant to this area of physics). So basically, scientists can happily say ‘Betelgeuse is alive and well as at *Current time – Distance in light years away*’, but can only speculate on what may have happened in the past 600 or so years as the light has travelled to us. So no, noone can say wether on the universal time frame Betelgeuse has exploded or not yet, but this to us humans on Earth is really quite irrelevant, as we will not see/hear/feel the effects until *explosion time + distance in LY*

    P209: A common misconception about constellations and the like, is that the stars are grouped together closely. This is balatantly false, while the stars within constellations may APPEAR to be grouped closely together, more often than not they are vast distances away from each other, just the different magnitudes of their brightness gives us the illusion that they are close together on a flattish plane. But on the note of the black hole distorting the constellation, this is a valid point, but chances are the distortion will not be enough to be picked up by the naked eye, or even most backyard astronomers. It will only be the top level astronomers that have access to the top level telescopes and star chart databases that will notice a difference.
    But the black hole could make a VERY interesting study indeed, scientists would be able to compare the beforehand distortion with the blackhole distortion, which could lead to some very valuable insight on the nature of black holes.

  179. Mike

    The fact is that most of the stars in the sky that we can see aren’t actually there anymore. It takes so long for the light from most of the stars to reach us that by the time we see it, all we’re seeing is what that star looked like possibly thousands of years ago. If Betelgeuse is “about to blow” chances are it already has, and we just haven’t seen it yet.

  180. phil

    acually its about 420-450 light years away from earth

  181. John Whitmore

    Did anyone think that the lumpiness of Betelgeuse has to do with planets orbiting the dying star? The star’s outer perimeter has now expanded beyond their orbits, so the star looks weird.

  182. Curtzilla

    Eta Carinae is a better prospect for a supernova soon.

  183. Topher

    “So the really lucky folks (for whom Betelgeuse is only visible at night) will get 24 hour days, everybody else will get at least some time with two suns in the sky” – So, wait a minute. The earth really is the center of the universe? I am pretty sure that it will be visible in the same relative direction as the earth rotates. Since it will only be visible for weeks, not a whole year, it will appear at the same time of day for everyone on the planet.

  184. supersajin

    2012 is not about destruction, death, end of the world etc. etc. it is about ascension, higher level of being, understanding who we are in the universe. If this does happen in 2012, and you don’t take advantage of the cosmic energies that will be hitting the earth than you will be missing the opportunity of a lifetime. We are all energy, this will be akin to getting a major energy boost.

  185. RCB

    So, as I understand it, there is a great deal of uncertainty about Betelgeuse’s likely fate, primarily because we don’t know enough in detail about what supergiants do as they are entering their terminal stages, because we haven’t seen any very close up.

    But adding to the confusion seems to be the difficulty in judging the distance to the star, which contributes to the margin of error in judging its actual size. The most commonly cited figure appears to be that used on Wikipedia, which cites Harper, Brown, and Guinan (2008). That is 643 ± 146 ly, which is a huge range.

    So, what I’d like to see, from someone who has access to good models with clearly-defined error margins and stuff, is a bunch of calculations that say, if we assume that Betelgeuse is as small as anyone thinks it could be, and as far away as anyone thinks it could be, and its supernova is as wimpy as possible, what will it look like from here? If it’s tiny and weak and at the near end, what will it look like from here? If it’s huge and has a maximal explosion and is far away, what will it look like from here? And if it’s huge and powerful and as close as it might be, what will it look like from here?

    And when I ask what will it look like, the question is the likely length and brightness of the first flash, then how long it will remain very bright, and how bright. And especially what would its apparent diameter be at different stages? Will it even have a chance of showing a visible disc? Does it have a real chance of being a large disc like the moon and sun?

    All this may depend greatly on your assumptions, so say so, and give a range of possibilities, along with why some are more likely than others.

    And in addition to stating are your assumptions, what are your sources, and what are your margins of error? I know it’s a bunch of work, but if it were laid out by someone with access to the models and the math, it would be much, much more interesting than the current pile of unsubstantiated or overly specific statements. This thread is for the most part a breath of fresh air, btw, with much more serious comments than anywhere else I’ve seen. That’s why I’m posting here.

    (Note that I’m not even bothering with the question of whether the light’s going to get here tomorrow or next year or in the next millennium. It’s very clear that we don’t know when to expect it based on what we know about the star. I’d love to see it, though, of course, and I’d like to know what it would be like if I’m lucky enough to live to see it.)

  186. jumjum

    If Betelgeuse would explode one thing is sure constellation Orion would be at its end right?

  187. Arvind Mishra

    Is it already exploded ? About 600 years back?

  188. rpetre

    Since the solution to the age old question about Betelgeuses current status can be found in “distance/speed of light”, I have found the solution! We travel to within 100 LYs of the star. If we do indeed find that Betelgeuse is still around, we can, upon our return to earth, report that it will NOT explode in our lifetime :) Now, if we can only convince Sarah Palin to board the “Rocket to Betelgeuse”

  189. rpetre

    Curtzilla is correct! Eta Carinae is probably closer to super nova than Betelgeuse. And since its size dwarfs that of Betelgeuse, it will offer the the added advantage of gamma rays in its “fireworks show”. More interesting is the fact that Eta Carinae may, in fact, be a twin or binary star. Too bad that darn cloud is in the way :(

  190. abc

    Actually it will be a doomsday event. A second sun in sky means rising temperatures, melting ice caps and severe drought. There will be climate changes, famines and eventually people will fight for the limited food. Mankind will survive, but most people will die.

  191. Victuz

    I have a silly question. Since Betelgeuse is 600 light years away (I thought it’s further away btw) doesn’t that mean that it would have to explode in 1411 for us to see it now? I mean. If it LITERALLY exploded right as I write this than the explosion would be seen on earth on 25′th of January 2611. Right?

    This seems correct since the “sun” that we see every day is about 7 minutes younger than the actual sun ;) . So is the moon (3-4 seconds younger).

    PS. I forgot to ask. How long is a supernova visible? I’m guessing that explosion of such magnitude doesn’t just “disappear” after 2 weeks. How long does it take? months? years? centuries?

  192. Mike F

    I’m sure Al Gore would be happy. We could actually have global warming for a couple of days

  193. rpetre

    Victuz, try a 1.5 seconds younger moon (light=186,000 mp second) and Betelgeuse, if it exploded today, would not be seen on earth until about 2611, give or take a few years. The super nova “should” be visable (naked eye) during the day for a few weeks and for centuries, ie the Crab Nebula, with the aided eye!

  194. Jay ~

    Actually, we humans are not the most perceptive creatures in the universe. Many of us can’t even seriously conceive a distance of 10 miles and have never jogged 10 miles…So to conceive light years, astronomical units, or even microscopic dimensions in the sub-atomic range such as angstrom units, is not possible, for most human brains. Our ego makes us feel that we know a lot about the universe! From microcosm to macrocosm! Human sensors, are not among the most perfect in the Universe and the scope for significant errors in measurement is of a highly appreciable order. So, communicating to fellow human beings, the properties of Betelguese which is bigger than the orbital diameter of Jupiter (around the sun) and that to estimated to be located some 600 light years away from our solar system, is at its very best a great joke/adventure. Meanwhile, “Wish all ye brave souls and spirits, Happy Speculations and Accurate Conjecturing!” A good and healthy way to spend your time. I like these calculations (Newtonian, though) which are indeed quite brave (@4):

    [Plus, also, what the Aussies and Kiwis say @134! Ha! ha! ha! :) Great sense of humor. The main article is so good and stimulating that today, nearly eight months from when it was written on June 1st, 2010 3:43 PM Tags: Betelgeuse, doomsday, supernova
    by Phil Plait in Astronomy, I am writing this 236th comment on India's 62nd Republic Day, Jan 26 2011(IST)! Comments will come in yet for some significant period of time. Great of you Phil! After saluting my national flag today, you are the first person I salute with admiration and genuine pride! My contact: lay_the_smack.down@yahoo.com]

    Yes, the comment, the brave calculation based on “Newton’s celestial mechanics”, by Jeff Adkins, is reproduced below:

    @4. Jeff Adkins Says:
    June 1st, 2010 at 4:14 pm
    Let’s suppose just for the sake of rough argument that when Betelguese goes it will be 100 billion times brighter than the sun. That’s not an unusual brightness for a supernova; they can often rival an entire galaxy.
    On the other hand, Betelguese is a lot farther away. At the speed of light, the sun is 8 minutes away. At the speed of light, Betelguese is 600 light years away. I estimate that is is therefore approximately 2.4 trillion times farther than the sun (600 years converted to minutes, divided by 8). And the intensity of light falls off as the square of the distance. So while it is intrinsically 100 billion times brighter than the sun, it is at the same time going to be 5.6 x 10 ^18 times dimmer because it is farther. The net effect is that Betelguese will wind up far, far dimmer than the sun as seen from earth. Something like 56 million times dimmer when both factors are taken into account.
    Now, that’s a bright thing in a night sky. But it isn’t going to rival the sun in brightness.

  195. Jay ~

    Today, early morning, while discussing, microscopic dimensions, @236 above, I quite forgot to write that even an Angstrom Unit, while being good enough for measuring atomic dimensions, is yet not considered “a small enough unit” for sub-atomic measurements, particularly in particle physics when we come down to pi mesons and other infinitesimally small particles like quarks et al. Can we really perceive the miniscule dimensions of these both in time (life interval) and space? AMU is another example used at microcosm level ostensibly known to humans. Now, for brevity, I wanted to sum it up by saying that both the macrocosm and microcosm cannot ever be clearly perceived by our mighty (but, puny human brains when weighed in the backdrop of the Universe) which is completely open-ended on both sides: Macrocosm and Microcosm! The electron, while being so miniscule proves its powers and might in electrical applications or when one gets an electric shock, or when lightning bolts strike and lightning is yet not fully comprehended by the world’s greatest scientists! How powerful and powerless are we! One sentence about Betelguese…If it goes off today earthlings have to wait approx 600 years to observe anything appreciable, and if, Betelguese has already blown off, say, some 500 years ago, earthlings have yet 100 years to begin noticing its after-effects; even gravitational field changes travel at the velocity of e.m. waves, and not faster!

    Over to Phil Plait…

  196. marika

    Hereafter, we can learn much from NGC 1952, let’s build a comparison:

    The star imploded in the crab nebula was between 9 and 11 M☉. The distance where it occurred it has to be about 6500 l. years. Historical records revealed that a new star bright enough to be seen in the daytime had been recorded in the same part of the sky by Chinese and Arab astronomers in 1054. Recent analysis of historical records have found that the supernova that created the Crab Nebula probably appeared in April or early May, rising to its maximum brightness of between apparent magnitude −7 and −4.5 (brighter than everything in the night sky except the Moon) by July.

    Dot.

    If we take Betelgeuse, we must consider that the apparent magnitude will be 10,8 times greater (6500/600) than the brighter than a shiny object appeared in 1054 skies, because the distance that separates us from Orion is 10 times lesser than Crab’s. Furthermore, if Betelgeuse has 20 M☉ , the mass ejected outside the core will be the double of crab nebula, and energy output should increase along with gravity as the energy issued from nuclear reactions will double.
    At this point i thought that we COULD expect an object holding an apparent magnitude at least 10 if not 20 times greater than that of the crab nebula. If the latter was brighter than Venus, it’s ok to have a Twin sun??? Forgive me if it’s not.

  197. marika

    And moreover, what we observe on betelgeuse is something that was happening about in 1411. So, if for a mere hypothesis the collapse started in XVth century, after 600 years it’d already gone into a supernova.

    The matter is to compute how much fuel is left in T, find the stellar mass, measure the issued spectral output which will give us a % of remaining elements, then convert them to T factor on how much time it would take to burn all remaining elements but iron. We could get an extimate by this way? I.e. If it would be silicon, we should expect a giant flare between 24h- I don’t know how muchtime it takes for other stages.
    However if it’d bring new infrared and visible light it could upset the unlucky emisphere where the summer may fall upon that day, maybe causing temperatures to rise a little bit, but only if the supernova would send a lot of energy even melting all the ice caps…
    One thing is for sure, it will happen someday, and it has to be brighter than the Crab’s star, in 1054 you would just sit from a distance 10 time closer than actual, and observe the crab nebula with a mass 2 times greater, sure if the first time was brighter than Venus the last will be a full moon.

  198. marika

    Alright, i’m betting there will be a chance for a second sun :

    The great star for seven days will burn,
    The cloud will make two suns appear:
    The great mastiff will be all night howling,
    When the great pontiff changes his land.
    (Century 2, Quatrain 41)

    Betelgeuse is one of the biggest stars known. One week is enough already for a daytime observation. Don’t get me wrong, i’m just doin…

  199. You know the Mayans came up with a date already

  200. Paul Cross

    When Betelgeuse goes supernova; would it be in a part of the sky whereby it might make the moon appear full for longer, i.e. at the correct angle to do this? Assuming it is bright enough.

  201. Colton

    Betelgeuse, Betelgeuse, Betelgeuse….

    Star go BOOM!!!

  202. laxsiya

    i can’t wait until BBBBBBBBBBOOOOOOOOOOOOOOOOOMMMMMMMMMMM!!!!!!!!!!!!!!!!!!!!!!

  203. Knowing my luck when it does finally blow, we will have 100% cloud cover in the UK for weeks and miss the whole thing.

  204. Stabeezy

    So not to be a doomsdayer here, but I think the reality of this thing is too convenient.

    Nibiru, or Planet X is supposed to cross into our solar system at the end of next year, and it sounds as though “someone” is setting up for an excuse for there to be a large unexplained ball in the sky when things start getting all weird.

    Why that is being hidden from us is pretty clear…tell everyone on the planet the destroyer is coming, and I’m pretty sure mass hysteria would break out. But it is most definitely being hidden…just for giggles take a look at where some astronomers pinpointed its location on google sky maps: -6.01931, -91.5903.

    Enjoy!

  205. Betelnuts

    Well if it takes 600 years the light to reach on Earth from tht giant star it means the image of Betelguese we see from here is 600 old so isn’t tht possible if it’s already exploded and we just can’t see it as of yet because of the speed of light???
    Please comment!

  206. Jackie

    Saw beetle juice on my I phone app after noticing weird reddish star, ended up on here reading all this bull and banter, god I am amazed people go on about stuff so much!!!! Is everyone doing this instead of reading on the toilet ,that’s my excuse what’s yours!!!!!!

  207. CX316

    I really hope it goes up soon, because quite frankly that’d be freakin cool to see *sigh*

  208. It may not HURT us, but I think I recall a calculation from a reputable source that if B/g went supernova, the radiation exposure here on Earth would be about the equivalent of a chest X-ray for all of us. Which is safe, but pretty cool.

    (Anyone know a cite for this?)

  209. caboose

    I’ve seen that it will take 600 years for the light from the explosion to get here in replies. and that it wont be as bright as the sun. Supernovas only last about a few seconds correct. That means when the light gets here from B/g it will only be for about a few seconds right, so we might miss it.

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