Jun 27, 2007

get your molecules from a dying star

Another amazing discovery from the world of astrobiology:
"Where we thought molecules could never form, we're finding them. Where we thought molecules could never survive, they're surviving," says Lucy Ziurys, an astronomer at the University of Arizona in Tucson, US.

Using the 10-metre radio dish atop Mount Graham in Arizona, Ziurys and her team searched the extended envelope of gas around VY Canis Majoris, a red hypergiant star estimated to be 25 times the Sun's mass and nearly half a million times the Sun's brightness.

There they found the telltale radio emissions of various compounds, including hydrogen cyanide (HCN), silicon monoxide (SiO), sodium chloride (NaCl) and a molecule, PN, in which a phosphorus atom and a nitrogen atom are bound together....

Because VY Canis Majoris is an oxygen-rich star, it was not expected to harbour so many interesting molecules. Oxygen atoms easily outnumber carbon atoms around such stars and would be expected to take up the available carbon by forming carbon monoxide (CO).

The discovery of molecules such as HCN and a carbon sulphur compound (CS) around VY Canis Majoris suggests that chemical composition can vary greatly within a circumstellar envelope. It also implies that the chemistry that leads to life may be more widespread in the universe and more robust than previous studies have suggested.
In related news:
Achim Tappe of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass., used Spitzer's infrared spectrograph instrument to detect abundant amounts of polycyclic aromatic hydrocarbons along the ridge of supernova remnant N132D. The remnant is located 163,000 light-years away in a neighboring galaxy called, the Large Magellanic Cloud.

"The fact that we see polycyclic aromatic hydrocarbons surviving this explosion illustrates their resilience," says Tappe.

These intriguing molecules are comprised of carbon and hydrogen atoms, and have been spotted inside comets, around star-forming regions and planet-forming disks. Since all life on Earth is carbon based, astronomers suspect that some of Earth's original carbon might have come from these molecules - possibly from comets that smacked into the young planet.

Astronomers say there is some evidence that a massive star exploded near our solar system as it was just beginning to form almost 5 billion years ago. If so, the polycyclic aromatic hydrocarbons that survived that blast might have helped seed life on our planet.
The one thing Jurassic Park got right: life will find a way.

1 comment:

TheTachyix said...

In regards to the first article: as all chemists have told me, reactions are just a matter of time and material. Given the immense size of the star, I'd be surprised if weird molecules weren't popping up.