Posted at 03:41 PM ET, 05/18/2011

Gliese 581d: The most Earth-like planet outside our solar system?


New dispatches from the “Goldilocks” zone. (By Lynette Cook via Associated Press)
Last fall, the hot — but not too hot! — new exoplanet on the scene was Gliese 581g.

Scientists touted it as the ultimate “Goldilocks” planet, meaning it was just the right size and just the right distance from its version of the sun, red dwarf star Gliese 581, to sustain human life.

The news was big. Readers hoping to cheat the coming apocalypse here on Earth told us they wanted to move there. Facebook groups were created. And then, as all newly minted celebrities do, Gliese 581g started tweeting.

Forget Earth Day! When's Gliese 581 G day?less than a minute ago via web Favorite Retweet Reply

But almost before we could say “how long is the flight?” news broke that 581g might not even exist, meaning data that scientists thought they received from the prospective planet might’ve just been fluke space “noise.” (Nearby confirmed planetary sibling, Gliese 581c, was ruled out in 2007 after it was deemed too hot to host life.)

All is not lost. Meet the third sibling, Gliese 581 d, which promises to be the less-flashy, less-controversial and possibly even-more-habitable answer to Goldilocks Zone researchers.

While once under the assumption that Gliese 581d was too cold, scientists at France’s National Centre for Scientific Research (CNRS) recently found that it’s capable of hosting oceans of liquid water, as well as clouds and rainfall. Its dense carbon dioxide atmosphere, in fact, is likely to give the planet a stable and warm climate.

But before you make plans to make the 20-light-year trip and set up shop in the Goldilocks zone, take into account that your surroundings would feel a bit foreign. Dim red light from its host star might provide Gliese 581d with far different scenery than earthlings, with their blue sky, are used to. Gliese 581d is also massive — its surface area is almost 5.6 times that of Earth’s. (Imagine the airfare.)

That said, change could be good. Take into account this bit from the Scientific Research center:

The most important implication of these results may be the idea that life-supporting planets do not in fact need to be particularly like the Earth at all.

Would you make the move?

By  |  03:41 PM ET, 05/18/2011

 
Read what others are saying
     

    © 2011 The Washington Post Company