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Look Up! It's A Star In The Midst Of A Violent, Bright Death

Originally published on October 16, 2011 12:07 am

Something violent is happening in the night sky, right now. And scientists studying the phenomenon said yesterday that with a pair good binoculars or a telescope you can see a star in its final throes causing a spectacular explosion called a supernova.

Even though the star is 21 million light years away from Earth, the explosion is the closest and brightest astronomers have found in decades. Today will be its brightest night.

Reuters reports:

The discovery, announced on Wednesday, was made in what was believed to be the first hours of the rare cosmic explosion using a special telescope at the Palomar Observatory near San Diego and powerful supercomputers at a government laboratory in Berkeley.

The detection so early of a supernova so near has created a worldwide stir among astronomers, who are clamoring to observe it with every telescope at their disposal, including the giant Hubble Space Telescope.

The star is located in the Pinwheel Galaxy, and you can spot it, weather permitting, above the Big Dipper. USA Today says the best time to catch it is just after sunset, before the moon brightens the sky.

The paper also explains a bit of the science behind what's going on:

The supernova belongs to the widely observed "Type 1a" group, born from runaway thermonuclear combustion in an ancient "white dwarf" star, the burned-out stub of a normal star that attains a weight 1.38 times heavier than the sun, then blasts itself apart. Type 1a blasts are 10 to 50 times brighter than other supernovas, and the light from the single exploding star is brighter than the light from an entire galaxy.

If such a blast had occurred in our own Milky Way galaxy, the light would probably be visible during the daytime. "In some senses, this is the largest, nearest thermonuclear explosion we can see," [astronomer Peter Nugent of the Energy Department's Lawrence Berkeley (Calif.) National Laboratory] says.

Reuters put together a video with an animation of what's going on:

The BBC spoke to Mark Sullivan, the leader of the team that made the discovery. He points out the last time they saw an explosion like this was in 1972 and before that in 1937 and 1898.

"Whilst it looks more or less like just another bright star, unlike its companions this supernova will soon fade away, and after a few days it will only be visible with larger telescopes," Sullivan told the BBC.

Update at 10:23 a.m. ET. How To Watch:

The Lawrence Berkeley National Laboratory has put together this video on how to spot the supernova using binoculars:

Update at 4:11 p.m. ET. What This Means For Science:

This afternoon, All Things Considered's Melissa Block spoke to Peter Nugent, the Lawrence Berkeley National Laboratory scientist who discovered the star.

We'll post their conversation here later. But here are a few highlights from it:

-- To put the distance in context, Nugent said they find one to two supernovas a night. Most of them are about one to four billion light years away and some of them are are as far as eight billion light years away. 21 million light years is practically next door by those standards.

-- Nugent says the best time to view the supernova is actually next week. Peak brightness is today, but next week the full moon will be gone and it will be much brighter.

-- Nugent says there are two things everyone should know about supernovas: Beyond helium, supernovas produce almost all the elements in the universe. The second thing is that this type of supernova — Type 1a — is used by scientists to measure how far things in the universe are. The light that supernovas emit is pretty much the same for all of them, so they are a good "standard candle" or constant. This kind of measuring also helps scientists understand how fast galaxies are moving away from each other.

-- Nugent added that there are a couple of things this supernova in particular can help with. First, because they found it in its early stages, it might be able to tell them why and how they explode. Specifically it might shed light on the companion stars that help these stars explode. (The Reuters video above, by the way, does a great job at explaining that aspect of it.) The second thing scientists can learn from this supernova is that it might help them better calibrate their cosmic measurements.

Copyright 2018 NPR. To see more, visit http://www.npr.org/.

MELISSA BLOCK, host: There's a rare astronomical event going on - a cosmic explosion that is so close and so bright, you can see it with a pair of good binoculars. It is a supernova in its infancy and it was discovered last month by astronomer Peter Nugent, senior scientist at the Lawrence Berkeley National Laboratory.

He joins me now to talk about his discovery. Welcome to the program.

PETER NUGENT: Thank you for having me, Melissa.

BLOCK: And first, what exactly is a supernova, the kind that you discovered here?

NUGENT: So the kind that I discovered is called a type 1A supernova. It's the death of a star. This is a massive explosion. This star started off a few times bigger than our sun. It burned all of its hydrogen to helium, helium to carbon and oxygen, and then it was just sitting there. This star is about the size of the planet Earth, but weighs about 1.4 times the mass of our sun when it's done all this burning.

And then it has a companion, in this case. We know that because otherwise, it would just sit there and glow and cool down and that would be the end of it. The companion feeds it with more mass and the temperatures and pressures build up on the inside to the point you have one of the largest thermonuclear explosions in the universe.

BLOCK: And that explosion is the supernova. How did you find it?

NUGENT: We run a survey called the Palomar Transient Factory and every single night, we take digital images of most of the visible sky and then we sort through everything that we find to look for these sort of needles in a haystack.

BLOCK: So you're looking for something that wasn't there before, in other words?

NUGENT: Exactly. Something that - boom - pops up out of nowhere.

BLOCK: And when you saw this boom pop up out of nowhere, did you know exactly what you were seeing?

NUGENT: No. At first, I actually thought, because I could see that it was in this very nearby galaxy called the Pinwheel Galaxy, I, at first, thought it was an asteroid that just happened to cross between us and it and that it would move in the next image that I looked at. And - it was still there, so I went back and I looked at all the data we had ever taken on this and nothing had ever been seen there before.

So that's when I got excited and that's when I alerted the collaboration to, hey, I think we've got something good here.

BLOCK: Peter Nugent, when we say this supernova is especially close, how close is it?

NUGENT: It is 21 million light years away, which may sound far, but in fact, is very, very close for a supernova. We find one to two supernovae a night and they're typically at a billion light years away.

BLOCK: And how bright is this that you can see it with good binoculars?

NUGENT: In astronomical terms, it's 10th magnitude. That turns out to be about one one-hundredth as bright as the human eye can see unaided, but with a pair of binoculars or even a six-inch telescope, you can see this quite easily in a dark sky.

BLOCK: What would you be seeing? What does it look like?

NUGENT: The Pinwheel Galaxy is a fuzzy spot. It looks like a little cloud and the supernova there is brighter than all the rest of the stars combined in the Pinwheel Galaxy.

BLOCK: So for people who are inspired by listening to this and want to go out and try to find this supernova - and they have to act pretty fast, right? Because it's not going to be around for long, not going to be visible for long.

NUGENT: It's not going to be around for long. The best time will be next week after the full moon, which is the 12th. And the Big Dipper where this supernova is located, just off the last two stars in the handle, that'll be at its highest point just after sunset.

BLOCK: And you go to the constellation, you go to the Big Dipper and then what do you do?

NUGENT: You swing to the last two stars in the Big Dipper and you make an equilateral triangle with the point headed north and it's right there at the other end of the equilateral triangle. And you can also look up online, there are many star charts for this supernova.

BLOCK: And it'll just look really bright? You would spot it right away?

NUGENT: You see the fuzzy patch in the Pinwheel Galaxy and this is the brightest thing there, so it's very, very easy to see.

BLOCK: Well, Peter Nugent, thanks for talking to us about your supernova.

NUGENT: Thank you very much for having me on.

BLOCK: That's Peter Nugent of the Lawrence Berkeley National Laboratory talking about the closest and brightest supernova to be found in decades. It's called PTF 11kly. Transcript provided by NPR, Copyright NPR.