Potentially Habitable Planet Discovered!

Update: Our discovery prediction paper is officially out, so please use this version.

A team of scientists discovered a planet in the Gliese 581 system that appears to be potentially habitable! This planet Gliese 581 g is part of a large multi-planet star system less than 21 light-years away. Courtesy of the press release:

The planet is tidally locked to the star, meaning that one side is always facing the star and basking in perpetual daylight, while the side facing away from the star is in perpetual darkness. One effect of this is to stabilize the planet’s surface climates, according to Vogt. The most habitable zone on the planet’s surface would be the line between shadow and light (known as the “terminator”), with surface temperatures decreasing toward the dark side and increasing toward the light side.

“Any emerging life forms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude,” Vogt said.

The researchers estimate that the average surface temperature of the planet is between -24 and 10 degrees Fahrenheit (-31 to -12 degrees Celsius). Actual temperatures would range from blazing hot on the side facing the star to freezing cold on the dark side.

If Gliese 581g has a rocky composition similar to the Earth’s, its diameter would be about 1.2 to 1.4 times that of the Earth. The surface gravity would be about the same or slightly higher than Earth’s, so that a person could easily walk upright on the planet, Vogt said.

It’s like a science fiction story! And our prediction for discovering such a planet by May 2011 appears to be accurate, and even a bit conservative. The next step is to examine the planet’s atmosphere for the presence of oxygen.

What an exciting time to be alive.

16 Responses to “Potentially Habitable Planet Discovered!”

  1. nicholas September 29, 2010 at 7:43 pm Permalink

    Exiting indeed, though it would be even more exiting if we could pay a visit :)

  2. Kevin H September 29, 2010 at 9:16 pm Permalink

    The mass of the planet is >= 3.1 times the mass of the earth according to wikipedia, with similar density to earth that’d be >= 1.45 the size of earth, which means the surface gravity wold be something like >= 1.45 times that of earth, so I don’t know if I’d like to vacation to a place where I weighed 82 Lbs more, but probably would be a perfect place to train special forces.

  3. insanesage September 29, 2010 at 11:04 pm Permalink

    Kevin I would hope that your “special forces” that are being trained are for protecting humanity against anything that might be out there and not against each other. If it were to fight each other we wouldn’t be there at all. Getting to another planet will take all of humanity working together.

  4. Darwin V September 29, 2010 at 11:32 pm Permalink

    Probably Earth vs Gliese 581

  5. Josef Nutgein September 30, 2010 at 1:30 am Permalink

    Life in the terminator
    Life in stasis
    Perpetual sun or shade
    You choose

  6. Kevin H. September 30, 2010 at 2:05 am Permalink

    I apologize. I am overweight. 190ish pounds is too much for my small frame.

  7. Nayan September 30, 2010 at 2:29 am Permalink

    When you are not sure of water on moon, and talking about earth like env. on planet away from 21 light year.

  8. Shawn September 30, 2010 at 4:32 am Permalink


    Cooperation did not get us to the moon. Competition did. And it drives more progress both in science and in nature. Cooperation can drive progress too, but in my opinion, not as much, and it’s definitely not the *only* way.

  9. Andreas Becker September 30, 2010 at 5:34 am Permalink

    Shouldn’t we first try to habit the moon and improve our “Space Shuttle”, instead of thinking about another habitable planet/star?

  10. Kate September 30, 2010 at 9:11 am Permalink

    I don’t think the article (at least not the bit provided here) is blatantly suggesting that we colonize this planet – I think it’s suggesting that it’s possible that this planet contains lifeforms that could evolve similarly to the way Earth’s did:

    “’Any emerging life forms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude,’ Vogt said.”

    Vogt said “emerging” life forms, not “invading” life forms, and I think the term “habitable” means any living thing, not just us.

  11. zach September 30, 2010 at 9:58 am Permalink

    you are ignorant. We just found a plante…as a whole we thought it wasnt possible. What the heck makes you think life can only be supported by oxygen, the same scientest that told you there werent planets that could support life other than ours? Why cant other species thrive on other substances other than what we do…don’ be stupid and closed minded. This article should prove this.

  12. Alex September 30, 2010 at 10:02 am Permalink

    20 light years away. Fastest space probes ever made – 250 000 km/h, which is less than 1/3600 of light speed (light travels ~300 000 km per second). Even setting the fuel problem aside: it would still take over 80 thousand years to reach that planet with this speed.

  13. pixelshifter September 30, 2010 at 12:08 pm Permalink

    nuke it!

  14. jp October 3, 2010 at 7:31 pm Permalink

    Larger mass doesn’t necessarily mean more gravity. A person weighs less on top of Mt. Everest than at sea level so it might have the same, less or more gravity as Earth due to a its mass being spread over different diameters. Current technology can’t get us there, but maybe when we as a species use our imagination and find our passion to explore we will develop the tools to take us there. Hopefully by then we will have the courage and wisdom to handle the trip. Also if there is life there then lets hope we don’t inadvertently bring back some alien disease. Biological hazards would be my greatest fear.

  15. Beth October 3, 2010 at 10:05 pm Permalink

    @jp: What about the diseases and bacteria that we would inevitably be taking with us?? Would we be responsible for killing life there? This is the same attitude that the Spanish had when they invaded the Americas. We have a moral responsibility to do no harm to other species and to our own, which must come before any scientific endeavor.


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