Thursday, September 30, 2010

Exoplanet found in habitable zone!

Artist's rendering of Gliese 581-g via Wired
Book your flights now kids, the first Earth-like exoplanet found in a "Goldilocks" or habitable zone has been discovered! Gliese 581-g is just 20 light years from us (that's right around the corner, right?) and is just the right amount of distance from it's parent star to have liquid water--a main ingredient for life here on Earth.
Click to enlarge; image: National Science Foundation
From the BBC:
"Our findings offer a very compelling case for a potentially habitable planet," said Steven Vogt, an astronomer at UCSC.

"The fact that we were able to detect this planet so quickly and so nearby tells us that planets like this must be really common."

Gliese 581g has a mass about three to four times that of Earth. It orbits its sun in 37 days and is thought to be a rocky world. It has enough gravity to possibly have an atmosphere.

The surface temp is estimated to be between  10F/-12C and 24F/-31C (so don't pack your speedo just yet). So think of it more like...
Don't worry, they double as sleeping bags.

Actually, that might not be the case. Seems that the planet is bigger than Earth and closer to it's star so it may not rotate--making it scorching hot on one side, colder than Hoth on the other. But a temperate equatorial zone may exist to sustain life. From Wired:

The new planet is about three times the mass of Earth, which indicates it is probably rocky and has enough surface gravity to sustain a stable atmosphere. It orbits its star once every 36.6 Earth days at a distance of just 13 million miles.

The surface of a planet that close to our sun would be scorching hot. But because the star Gliese 581 is only about 1 percent as bright as the sun, temperatures on the new planet should be much more comfortable. Taking into account the presence of an atmosphere and how much starlight the planet probably reflects, astronomers calculated the average temperature ranges from minus 24 degrees to 10 degrees above zero Fahrenheit.

But the actual temperature range is even wider, says astronomer Steven Vogt of the University of California, Santa Cruz, who designed some of the instruments that helped find the planet. Gravity dictates that such a close-in planet would keep the same side facing the star at all times, the same way the moon always shows the same face to Earth.

That means the planet has a blazing-hot daytime side, a frigid nighttime side, and a band of eternal sunrise or sunset where water — and perhaps life — could subsist comfortably. Any life on this exotic world would be confined to this perpetual twilight zone, Vogt says, but there’s room for a lot of diversity.

Great, now let's build us a starfleet and get going!

More from BBC, Wired, Washington Post, MSNBC, NY Times, and LA Times