Category Archives: supernova

A Haunting Gallery of Destruction

The Deaths of Stars

This HST mosaic image of the Crab Nebula shows a six-light-year-wide expanding remnant of a supernova explosion. Courtesy STScI.

Stardeath produces some of the most intricate-looking objects in astronomy. If you have ever gone to the Hubble Space Telescope’s Web site and searched for planetary nebulae, you know what I mean. Giant stars produce giant explosions, like the long-known Crab Nebula.

The Eskimo Nebula (NGC 2392). The intricate "face" is a bubble of material being blown into space by the central star's intense "wind". Courtesy STScI.

This Hubble Space Telescope image shows us what the supernova remnant is made of (hydrogen gas, particles of heavier elements), and also shows us the structure of the nebula and how it’s influenced by the neutron star at the center. That neutron star is what’s left of the original star — a dense object spinning more than 30 times per second.

Stars like the Sun go a bit less violently, huffing off their atmospheres for millions of years before collapsing to make white dwarfs. The radiation from the central star continues to light up the remains of the former star, creating complicated visions of stellar death. The Eskimo Nebula (right), is a fine example of such a sun-like star’s death. The remains are called a planetary nebula, one of those odd misnomers in astronomy that has nothing to do with a planet, but is a nebula. This sunlike star began to die some 10,000 years ago, blowing bubbles of gas out away from itself and flinging its outer atmosphere to space. Our own Sun might look like this some billions of years from now.

Well, I’ve been long fascinated with the images of star death, ever since I wrote my first book (with Jack Brandt), about Hubble Space Telescope science (called Hubble Vision).  A few years ago when I did an update of one of my more-popular planetarium shows, called Hubble Vision 2, I had a great selection of star death images to choose from to tell the story of stellar demise. I wrote about sun-like stars, “Hubble’s images of these stars in their death throes comprise a haunting gallery of destruction.”

As is always the case with my shows, I knew that the soundtrack artist (who also happens to be my husband and co-producer) would find a way to make the scene  memorable with his trademark space music and video choreography. The scene in the show is a solemn, beautiful procession of planetary nebula images that bring home to audiences the majesty of a star’s passing.

Fast-forward a few years to this month, and Mark has now released the music from that show soundtrack in an album called Geodesium Stella Novus (where you can preview and buy the album if you’re interested). And, he created a music video based on that planetary nebula scene that really does bring home the majesty of that haunting gallery of destruction we first introduced in the show. We created a fulldome version of the music video, which you might get to see someday at your local digital planetarium.

But, we’ve also got a “flat-screen” version available on our Youtube channel for people to watch and I’ve embedded it below.  The piece of music is called “Light Echoes”, and it accompanies these gorgeous views of star death, ranging from supernova remnants to planetary nebula, as cosmic art.  It’s not a new concept — the universe as art. But, you have to admit, when you see the way nature has arranged the aftermath of stardeath, it can look evocative, haunting… and artistic!

Exploring Gamma-ray Bursts

With Dale Frail

Artist's concept of a powerful beam of gamma rays.

The latest episode of The Astronomer’s Universe is up live on Astrocast.TV and it’s all about those powerful flashes of light in the cosmos called gamma-ray bursts. These outbursts mystified astronomers for more than four decades until they figured out some plausible mechanisms for what causes them.

For this segment, I interviewed Dr. Dale Frail of the National Radio Astronomy Observatory’s Very Large Array radio telescope installation in New Mexico. He and a group of colleagues have been observing these monster explosions, particularly in radio wavelengths and have recently made great strides in deducing the engines that power gamma-ray bursts.  Essentially there are two mechanisms:  massive supernova explosions that collapse matter into a black hole and/or the merger of two really massive objects such as neutron stars.  Each gives off bursts of gamma rays.   Watch the episode for Dr. Frail’s take on GRBs.  Also, head over to the main Astrocast.TV web site and see our other great offerings, including Harold Gellar’s tour of the night sky (click on the “Our Night Sky” link) and Bente Lilje Bye’s fascinating study of volcanoes at the link for “A Green Space, A Green Earth”. Enjoy!!