http://en.wikipedia.org/wiki/SN_1054

Crab supernova

&

http://en.wikipedia.org/wiki/SN_1987A

&

http://en.wikipedia.org/wiki/Sanduleak_-69%C2%B0_202a

Just so I can cut & paste to ensure the correct spelling!

Minor note from that last one there :

Four other LBVs (Eta Carinae included) might join it in a few million years.

If I recall right, then Eta Carinae could go off anytime or in a few hundred thousand years. I’d be surprised if it lasted another million years or so – although I probably won’t be around still then to be surprised but y’know what I mean!

But then both SN 1987a and SN 1054 formed pulsars, not black holes; unless someone has information I’m not aware of?

SN 1054 formed Messier 1 the Crab Nebula.

Alas, in the case of SN 1987a I’m not sure *what* it formed and I don’t know that anyone, really is. I believe folks have been looking for an expected neutron star remnant and haven’t as yet found one.

Unless I’m mistaken which is, natch, always a possibility.

This could mean that it formed a black hole instead or it could, alternatively, mean that a neutron star was formed but that we can’t see it for some reason or perhaps the whole star just blew apart without leaving a stellar corpse of any kind at all.

After all, SN1987a was unusual in a number of respects – not least being that its precursor star, Sanduleak -69° 202a, was a blue supergiant rather than the expected red variety.

***

BTW. Wikipedia gives a distance of 168,000 light-years for SN 1987a meaning the supernova happened approximately 168,000 years prior to its observation in 1987.

By comparison SN 1054 detonated at a distance (& thus light travel time of) 6,300 hence was still younger in real terms.

Since SN 1979c happened 50 million light years away, and is therefore approximately 50 million + 31 years old, while SN 1987A was seen by us 8 years later, but is located in the Large Magellanic cloud, about 168,000 ly away, so it actually blew about 168,000 + 23 years ago, and is far more recent.

Not only that, but SN 1054 was seen 956 years ago, but is only about 6,500 ly away, so it happened approximately 6,456 years ago, and is by far the youngest supernova we know about…

…assuming a hypothetical objectivity that is, in practice, impossible.

But then both SN 1987a and SN 1054 formed pulsars, not black holes; unless someone has information I’m not aware of?

Most astronomers constantly toil away at the half-assed conventional ‘explanation’ designed to soothe what they consider to be the typical public’s capacity to understand how it works (that is, dumb it down to nearly opaque levels) in which all they ever offer is based on the idea that light takes some finite time to travel from one point to another through an intervening space.

Then they declare that we are looking at distant stuff “in the past” and leave it at that.

That is grossly incomplete.

There is no need for this ridiculous confusion. Yes, from our standpoint 50 million light-years away, the light left the source 50 million years ago. BUT, we receive the information the light carries in proper sequence 50 million years later over here. We apparently see things as they transpired in M100 50 million years ago, to the tiniest fraction of a second, believe it or not.

HOWEVER, there are certain caveats:

1. The M100 galaxy contains stars and other stuff that emits detectable light that is not all situated at exactly the same distance. Some parts of that galaxy are tens of thousands of light-years farther away than other parts. It doesn’t matter: what we actually see is a galaxy in which the nearer parts ARE tens of thousands of years displaced from other parts further removed. This is true of ANY galaxy we look at. In other words, we can NEVER observe any galaxy to see it as it is at any given time, nor can the galaxy view ITSELF as occupying any particular moment in time that is contemporary with any point oberver within it.

2. While we perceive light to travel over some finite distance over some finite span of time, the theory of Special Relativity emphatically informs us that, from the point of view of photons of light, no time whatsoever elapses between emission and absorption. THAT means, quite obviously, that from the viewpoint of photons, absolutely no spatial distance has been bridged, and the ‘crossing’ was instantaneous. The implication is that – from the viewpoint of the photon – no time has elapsed and no space has been crossed: the instant a photon is ‘emitted’, is actually the same instant that it is absorbed by some suitable detector, like our eyes or our instruments. Special Relativity loudly proclaims this, yet few have been paying it any attention.

The ultimate implication is that we do NOT see the Sun as it “was” 8.3 minutes ago, but as it is in our mutual ‘now’. We look at a quasar 8 billion light-years away, we are looking at it is in our mutual NOW, NOT as it was 8 billion years ago. We capture microwave photons from the Cosmic Microwave Background and declare it some 13.7 billion years old and as distant at the time of emission, but that’s just not true: we are viewing that CMB as it is in our mutual NOW, NOT as it was 13.7 billion years ago.

There can be no swifter conveyance of information than light, and whatever causal influence that is transmitted at a distance must necessarily arrive as soon as it is transmitted. Special Relativity demands it. Quantum mechanics demands it. The popular notion of “now” (which most astronomers and physicists themselves stubbornly harbor) MUST adjust and assimilate the more complete definition that makes proper sense according to what our theories actually say. Special Relativity and Quantum Mechanics have been howling loudly for the better part of a century, but we haven’t been very good at listening. In fact, we’ve been as good as deaf.

To continue to wow ourselves over the mezmerizing illusion of ‘lookback time’ interpretations is to erase the essential gifts of Special Relativity. How this stubborn delusion might have messed up our theoretical thinking in the meantime (over the course of a full century!) remains to be seen, but it seems quite clear that the pop explanations have done nothing but confuse an issue which shouldn’t have been confusing at all – and encouraged physicists themselves to think in equivalently dumbed-down terms.

How long shall it take to shift this entrenched paradigm? And, in the current atmosphere of physics theory which properly casts a wary eye on every detail and crackpot submission, how can the likes of an independent genius such as an Einstein flower? Many noteworthy theoretical physicists have gone on record to say that the insight of an individual genius such as that exhibited by the equivalent of a Newton or an Einstein is probably required to break through the apparent current impasse towards a new understanding, String Theory or Loop Quantum Gravity notwithstanding. That may be true even though there are very interesting flights on the wing produced by a fantastic legion of gifted people. I just doubt that the physics community has exhausted all the fundamental implications they have already had to work with over the last 100 years.

Nevertheless, the observed sustained strong x-ray emission from the spot indicates one or the other must be there. There isn’t any other known way to account for it.

This suggests that the expanding gaseous remnant SN 1987A might begin to clear enough to reveal a signal from the collapsed remnant (expected to be a pulsar) within the next 5 to 10 years. Stay tuned to THAT guy’s coming-out party.

You know if we had a spacecraft that could travel 13 to 15 billon light years form Earth we could watch the big bang live.

Unfortunately, that hypothetical spacecraft would still have missed the Big Bang’s Opening Act by over 13~15 million years. The show would be long over – and the space over *there* would be as old as the space *here* – although it’d still be an awesome feat to accomplish!

I imagine that if we could such a craft, it would show us something very different about the region it arrived in and how it had evolved from how *we* see it now – & looking back towards us it might see the light leaving the Milky Way when our own home Galaxy was just forming – or even beforehand.

That’s as I (rather fuzzily) understand things anyhow. If someone with a better understanding of this question than me wants to chime in and correct me that’d be excellent.

@48. Smitty Says:

@ everyone – Has anyone clicked on #7’s name?

Yes, just now out of sheer morbid curiousity & .. Oh. Dear. What. The!

“but wouldn’t the gradient for a low-mass black hole be similar to that of a high-mass neutron star? i would certainly expect the disk around a stellar-mass black hole to be more than a few miles out, which would be safely above the surface of a neutron star.”

From what I can recall of black hole dynamics, if earth was of neutron star density it would be about the size of a basketball. To collapse it to a black hole, it would be about the size of a marble(2 or 3 cm diameter). The gradient would then be much sharper, since we’re talking a G field sufficient to stop light at a distance of a cm from the BH “center”, another one cm. further out would reduce that G field to 1/4 as intense. For the neutron body, we’re talking 20 cm or so for each such reduction and with equal masses, that G field would already be 1/100 th (just above the surface of the neutron body), as intense as for the BH at its event horizon.

We don’t really know what goes on inside the BH, we just have a lot of speculation but one idea is that the particles that transfer force between particles(even inside neutrons) can’t go “uphill” against the intense G field, so the particles just collapse into the false vacuum, thus, in this POV, there is no “singularity”(ie, infinitely dense matter) at the center of the black hole. All the mass just becomes the energy of the false vacuum.

Gary 7

Has anyone clicked on #7′s name?

Wow. Just, wow.

@ OmegaBaby

By monitoring the explosion. Astronomers can mathematically predict that a star of a certain level of mass will go supernova in a certain way and with a certain level of intensity.

It is also possible that they might have been “monitoring” that star because it was showing signs of its imminent death. IE: shedding massive amounts of mass which then results in another type of supernova, also with predictable mass levels and outcomes. At 50M Ly though, I’m not sure if direct monitoring is possible though.

If you were not able to gather from this article why this is exciting for astronomers, there’s really no help for you here.

Try something more like this, maybe -> http://www.readingtolearn.com.au/

This excites me about as much as putting ointment on my Roids.

Too much information there, mate.

I don’t want to know about your haemorrhoids and I strongly suspect nobody else here does either. Please spare us.

Also if you find this that uninteresting why bother commenting to say so?

How about coming clean and quit lying about other life in our Universe and on our planet.

Why assume people are lying? What evidence do you have to support your extraordinary and rather offensive claim there?

Other life on our planet? Yeah, there’s stacks of it – from chimpanzees and elephants to goldfish and insects – all of it natural and evolving here over aeons. But I take it that’s NOT what you’re referring to though?

Alien life elsewhere? Well a lot of smart people are looking for it. If you want to help then why not sign up to SETI at home or something like that, do some research and don’t just troll or believe nonsense, please. That would be much more fun and much more useful than falling for and trolling about dumb and tedious “flying saucer” conspiracy theories.

“Why do black holes emit x-rays when nothing is supposed to escape from them?”

The X-rays are emitted from material traveling just outside the event horizon. Saying that the BH emits them (or emits any other radiation) is just a verbal shortcut for that situation.

Neutron star wind or Black hole, either way these findings enhance and add to our astronomical store of knowledge and this is a fascinating bit of news. Well done.

Youngest though? What of SN1987 A and its central object :

http://en.wikipedia.org/wiki/SN1987A

Do we still have no idea if a neutron star or Black Hole formed there? Any developments there likely to come to light soon~ish?

***

PS. Haven’t yet read the comments here – sorry if this has been said already.

It is entirely correct, as an entry level of understanding, to say that this supernova took place ~31 years ago. The fastest known achievable speed is the speed of light in a vacuum. This is a pretty good match for what really happens in space all the time. The reason is that we can say this supernova is only 31 years old, is that it was only in this timeframe that it was detectable to us. It is not possible even in principle, to have detected it any sooner. That is a true statement of our understanding of General Relativity.

The master class can allow that this supernova actually took place 50 MYA + 31 years. However even then, there is no technology*, no physics*, that would have allowed us to see it prior to 31 years ago. This is interesting but not actionable information.

It works in the reverse too. An observer of us in the vicinity of the supernova, would only be able to see us with a time lag of 50 million years. We are eternally separated not only by space, but by time as well.

* = This discounts speculative warp drives, hypothetical tachyons, and unobtainium.

Dude, if you’re color blind, no amount of explanation on my part can inspire a sense of a rainbows beauty in you.

The same is true here. You either get it,,,or you don’t. So sorry for you,,,

20. AJKamper

“either the additional energy would have to be the result of the smaller size of the black hole (with the correspondingly more powerful gravitational pull) or the larger mass of the black hole generally. Is that the case?”

It’s just the gravitational GRADIENT that pulls people, space craft or planets apart. The gradient is the difference in acceleration between, say, your head and your feet.At four thousand miles from the earths center, that gradient is miniscule. If earth was a black hole(about the size of a marble) the gradient would be extreme when close to its(event horizon), but of course, at 4000 miles away the gradient would be the same as it is now. All that flows from the inverse square law,ie, double your distance from the point source and intensity decreases by the square(ie, 1/4th as intense). I’m only 6’1″ so to experience a significant gradient way out here I’d have to be about 4000 miles tall(twice the distance from earths center as I was to begin with). Then my feet would still experience 1 G but my head would experience 1/4th G.

Gary 7