Thursday, September 30, 2010

New Earth

Yesterday two scientists announced the discovery of the first Earth-like planet lying in the habitable zone of its star. Co-discoverers, who will publish in the Astrophysical Journal, are R. Paul Butler of the Carnegie Institute and Steven Vogt of UC Santa Cruz.

It's not exactly Earth -- more like a swollen Mercury, in that the planet is three times the mass of Earth, only 14 million miles away from its star, and does not rotate. The star, Gliese 581, is a dwarf, so even at such close distance any potential water will not have been boiled off the surface. The planet, which goes by the unromantic name of Gliese 581g, orbits the dwarf star every 37 days.

And it's only 20 light years away! That is, as Vogt pointed out in a video, close enough to send a probe with today's technology, even though we might not get any information back for a few hundred years.

The star system appears, from Earth, to be in the constellation Libra. I wish the weather were clear here in Seattle (it's not) -- tonight I'd like to be able to go up to the roof, gaze at Libra, and wonder: Who's there?

3 comments:

Orion said...

It's way cool to have finally spotted a terrestrial planet in the habitable zone around another star- especially a star so dissimilar to Sol. We can hope that such planets will turn out to be common as our detection methods get better.

A nitpick- the planet certainly does rotate, or it would not present one face to its star at all times. It's tidally locked to its primary like our moon is to Earth. Its rotational period is equal to its year length- a minimum-energy configuration.

bluesman miike Lindner said...

WHO'S THERE?

WE ARE!

AND WE VALUE OUR PRIVACY, THANK YOU VERY MUCH!

("BROODMATE, THESE EARTH PEOPLE...NO SENSE OF COURTESY AT ALL..."
"I'M HIP, BROOD...I/WE/THEY WERE JUST TALKING ABOUT THEM TO THE AQUA-PEOPLE

bluesman miike Lindner said...

THE LAST ROTATION..."
"CRUDE BEINGS."
"THAT DON'T TELL THE HALF OF IT..."