1883-2013: All the exploding stars

An animation showing all the stars that have exploded in the last 130 years, starting with a supernova seen in the Andromeda Galaxy in 1885, just below our galaxy towards the left, and ending with Supernova 2013ek, discovered a few days before I uploaded this video. The animation has two parts, first where each supernova stays on the image, and then we rewind back to 1883 and watch them all again but each explosion appears and fades. Each part lasts 130 seconds.

At first there were not many supernovae being discovered; there were no dedicated searches for them and people only noticed the nearby brighter ones. Later, telescopes got better, searches got better and the discoveries start flooding in. Ten years passed between the Andromeda supernova and the discovery of the next one, but the last time a whole month passed without a supernova being spotted was in July 1993.

The bottom right part of the image is the part of the sky that's only visible from the southern hemisphere, and you can see that there are relatively few supernovae there. Most of the Earth's population, and therefore most of the astronomers, are in the northern hemisphere so stuff happening in the south is less likely to get spotted.

And you can see in the first part that the closer you get to the plane of the galaxy, the fewer supernovae there are. Thick clouds of dust block everything from view there, to the extent that even though supernovae have certainly happened in our galaxy during the last 130 years, we haven't seen them. The dust is so thick that it's easier to spot supernovae a billion light years away than it is to see one in our own galaxy.

The big smile that appears at the bottom left towards the end is Stripe 82, a part of the sky observed by the Sloan Digital Sky survey for three months of the year in 2005, 2006 and 2007, to search for supernovae. They found nearly 500 of them.

In the second part, when the discoveries start to get really frequent, you can see them kind of sloshing around the sky. We can only see supernovae that are far enough away from the sun in the sky to be seen at night, and so as the sun moves around the sky over the course of a year, it blanks out a portion of the universe for us as it goes.

I was inspired to create this animation by two works of art: "All the dead stars" by Katie Paterson, and "1945-1998" by Isao Hashimoto. The all sky image is by Axel Mellinger, and the music is "Sleep Chamber" by Zander One. The supernova data comes from the list maintained by the Central Bureau for Astronomical Telegrams (http://www.cbat.eps.harvard.edu/lists/Supernovae.html).