Some new research just released asks a question near and dear to me: are there thousands of spinning white dwarfs in our galaxy, just waiting to explode as they gradually slow their rotation?

The answer is very probably yes. Let me be clear, as I always must be when covering topics like this: we’re not in any real danger from these things. Space is vast, and supernovae are few. If these things were that volatile we wouldn’t be here to talk about them in the first place.

But it’s still a very cool scientific question, and actually a fairly simple concept. Here’s how it works.

Imagine a binary system of two stars like the Sun, orbiting each other. One star nears the end of its life, swells up into a red giant, and blows off its outer layers. After a few millions years, all that’s left is its core: a dense, hot ball called a white dwarf. The size of the Earth but with the mass of a star, white dwarfs are pretty weird. They have incredibly strong gravity, which wants to crush them down even further, but they are supported by the electric repulsion of electrons, which is a pretty mighty force. It’s an uneasy truce.

It’s made even uneasier by the other star. It too eventually swells up, and can start to dump matter onto the dwarf (like in the picture above). If enough mass piles up, the immense gravity of the dwarf can induce nuclear fusion. Sometimes the material explodes, flaring in brightness, and we get a nova. Other times, if enough matter piles up — making the total mass of the white dwarf a bit more than 1.4 times that of the Sun — the ignition of fusion can cause a runaway reaction in the star, disrupting it entirely. The white dwarf tears itself apart, and you get one of the biggest and most violent explosions in the Universe: a supernova.

But there’s a hitch. (more…)

A couple of weeks ago, astronomers spotted a star exploding in the nearby face-on spiral M101. They quickly determined it was a Type Ia, the kind used to calibrate the cosmic distance scale, and therefore a star of exceeding importance: we don’t see them close by (well, if 20+ million light years is "close", which it is to astronomers) very often. This one promised to get bright enough to study extremely well, which will help us understand these "standard candles" better.

Astronomers at Oxford University got a great shot of the galaxy and exploding star this week using a telescope located in California:

[Click to galactenate.]

The supernova is labeled. It was found by the Palomar Transient Factory, a group of folks looking for nearby supernovae, and was given the temporary name PTF 11kly; the official designation is SN 2011fe, the 136th supernova seen so far in 2011 (they’re named alphabetically for a given year, so the first 26 are 2011a – z, the second 26 are 2011ba – bz, etc.). This image was taken using a 0.8 meter telescope at the Las Cumbres Observatory Global Telescope Network; that’s a relatively small ‘scope, which tells you this a pretty bright object!

In fact, it appears to be reaching its peak brightness right now, and should be visible in binoculars. If you have a good view of Ursa Major, currently in the northwest at sunset, finding it shouldn’t be too difficult. Any decent star chart will show it (here’s one on wikipedia, for example). It’s raining here in Boulder (figures) but I’m hoping to get a chance to see it with my binoculars soon. Supernovae usually brighten for a couple of weeks and then fade more slowly, so if you can’t see it tonight or tomorrow it’s not critical, but of course the sooner you look the better.

Image credit: BJ Fulton/LCOGT. Tip o’ the accreting white dwarf to Dan Vergano (you should follow him on Twitter for lots of sciencey updates).

Images are starting to come in already of the new supernova in the nearby spiral galaxy M 101. Here’s a color image of the exploding star from the Faulkes North telescope on — wait for it — Haleakala:

[Click to embiggen.]

That’s color and very pretty, but I think this one is more impressive, showing the supernova gaining in brightness by a factor of six in a single day:

[Again, click to endeflagrate.]

That’s taken by the Palomar 48 inch telescope in California. The images show M 101 on August 22, 23, and 24. You can see (or not see in this case) how it wasn’t there on the first night, shows up on the second, and is now much brighter. It will get brighter yet, and may get into range of visibility using good binoculars! Certainly even a small telescope will be able to see this supernova once it reaches maximum brightness, which won’t happen for at least a week, if not more.

Right now, the Moon is a waning crescent, so it won’t be a problem for 10 days or so. If you have a telescope and a camera, get out there!

Credits: BJ Fulton, LCOGT; Peter Nugent and the Palomar Transient Factory

Attention all astronomers! There is a new Type Ia supernova that has been seen in the nearby spiral galaxy M101, and it’s very young — currently only about a day old! This is very exciting news; getting as much data on this event as possible is critical.

Most likely professional astronomers are already aware of the supernova, since observations have already been taken by Swift (no X-rays have yet been seen, but it’s early yet) and Hubble observations have been scheduled. Still, I would urge amateur astronomers to take careful observations of the galaxy.

[As an aside, I'll note that this supernova won't get bright enough to see naked eye and poses no threat at all to us here on Earth. It may be visible in decent-sized telescopes, though, and as you'll see this may be a very important event in the annals of astronomy.]

[UPDATE: Joseph Brimacombe took a very nice shot of the new supernova using a 20" telescope in New Mexico. Thanks to Surak who left a comment below about this.]

So why is this a big deal?

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The Carina nebula is a sprawling, monstrous complex of gas located a mere 7500 light years from Earth. Hundreds of light years across, it’s massive enough to create thousands of stars like the Sun. Tens of thousands.

And churn out stars it does. Embedded in the nebula are several clusters of newborn stars, and many of these stars are so massive they’re nearly at the limit of how big a star can be without tearing itself apart. Stars that big explode as supernovae, and a new mosaic by the orbiting Chandra X-ray Observatory indicate they’ve been popping off in the nebula for quite some time:

[Click to enchandrasekharlimitenate.]

This image is pretty amazing: it’s a mosaic of 22 separate images by Chandra, covering 1.4 square degrees (seven times the area of the full Moon on the sky), and represents an exposure time of 1.2 million seconds! Since it shows X-rays coming from astronomical objects, it’s false color: red is from lower energy X-rays, green is medium energy, and blue from the highest energy photons.

The diffuse glow is from two sources: the stellar winds from those massive stars slamming into surrounding ambient gas at high speed, and from the shock waves generated when supernovae explode. Both are extremely high-energy events, and produce copious amounts of X-rays. That long, horizontal arc is probably the edge of a bubble, a shell of gas piled up from the winds of stars and supernovae like snow piled up in front of a snowplow.

That’s evidence right there that Carina has been cranking out supernovae over the past few million years. Interestingly, it’s what’s missing that provides more proof. (more…)

I swear, I need to trust my instincts. As soon as I saw the article on the news.com.au site desperately trying to link Betelgeuse going supernova with the nonsense about the Mayans and 2012, my gut reaction was to write about it.

But no, I figured a minute later, this story would blow over. So to speak.

I should’ve known: instead of going away, it gets picked up by that bastion of antiscience, The Huffington Post.

Grrrr.

The actual science in the original article is pretty good; they talked with scientist Brad Carter who discusses the scenario of Betelgeuse going supernova. The whole story is pretty interesting — I wrote about it in detail the last time there was nonsense about Betelgeuse blowing up — but in a nutshell Betelgeuse is a red supergiant star in Orion with about 20 times the mass of the Sun, and it’s very near the end of its life. When stars this massive die, they explode as supernovae. The distance to Betelgeuse is unclear (it has a very puffy outer atmosphere which makes distance determination somewhat dicey) but it’s something like a bit more than 600 light years, way way too far away to hurt us.

It’s the question of when that the two articles go off the rails. Betelgeuse may explode tomorrow night, or it may not go kerblooie until the year 100,000 A.D. We don’t know. But given that huge range, the odds of it blowing up next year are pretty slim. And clearly, the original article was really trying to tie in the 2012 date to this, even when it has nothing to do with anything. The tie-in was a rickety link to scuttlebutt on the web about it, but that’s about it.

What’s worse, the HuffPo article attributes the date to Dr. Carter himself, but in the original article he never says anything about it; the connection is all made by the article author. Given how popular HuffPo is, I imagine a lot of people will now think an actual scientist is saying Betelgeuse will blow up in 2012.

OK then, tell you what: I’m an actual scientist, and I would give the odds of Betelgeuse going supernova in 2012 at all — let alone close to December, the supposed doomsdate — as many thousands to one against. It’s not impossible, it’s just really really really really really really really unlikely.

Really.
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When Kathryn Aurora(!) Gray was born, the light from Supernova 2010lt had been traveling for about 239,999,990 years. Ten years later, she spotted it on a computer monitor and became the youngest person to ever discover a supernova.

Lots of folks have been covering this story (and making sure they wrote out her middle name, which is kinda awesome), including the Hive Overmind’s DiscoBlog and Universe Today, so I won’t go into details. But this is pretty nifty. It used to be that it took long, laborious hours at the eyepiece to find exploding stars, and not many were found in a given year — heck, the first supernova in 1987 wasn’t seen until late February (and went on to become the most famous supernova in 400 years).

Now, though, automated telescopes scan the sky, and computer programs have taken away a lot of the burden of supernova hunting. To give you an idea of how many are found every year, they are named in alphabetical order, a-z, so that the 27th of the year is then aa, the 28th is ab, and so on. 2010lt was therefore the 332nd supernova found in 2010! Amazing. Each one is important, too, since many supernovae act oddly, and you never know when one will be special and indicate something new… and even if it’s just another run-of-the-mill explosion, we’re still talking about the detonation of a mighty star releasing energy quintillions of times that of the Sun!

So congratulations to Ms. Gray, and I hope 2010lt is the first of many adventures she has with the sky.