A Field Guide to Supernovas

Two white-dwarf stars have collided to form a brilliant supernova encased in silicon. It’s a rare way for such supernovas to form--normally they happen after a single white dwarf borrows a bit too much matter from a nearby red-giant star. Like a kid stealing cookie dough, a gigantic, unstoppable fusion reaction typically ensues.

But in this case, researchers believe, two nearby white dwarfs spiraled in toward each other until their combined masses set off the explosion.​

Why stop with just one supernova? The universe is a seemingly endless source of cataclysms, and NASA is getting increasingly good at catching them on film. You can admire the Purple Rose of Virgo (a Type Ia supernova handy for measuring the universe), brush up on your Type I vs. Type II supernovas in constellation Hercules and check out the brightest ever and the farthest-away.

There's also the Milky Way’s youngest supernova (looks a little like an evaporating gobstopper), a bowling ball headed straight for the Pillars of Creation and a whole gallery gleaned from the Hubble Space Telescope's illustrious career.

Is too much galactic drama threatening to make your brain explode? Take a breather with something merely whale-sized: 12 narwhals lined up in the Arctic sea ice (the pic recently was named one of the best wildlife photos of 2007).

(NASA/Dana Berry/Sky Works Digital)