[Red Badger]

Artistic representation of all the five known potential habitable worlds including now Gliese 581g, the best candidate for an Earth-like exoplanet so far. All of these planets are superterrans (aka Super-Earths) with masses estimated between two and ten Earth masses. Numbers below the planet names correspond to their similarity with Earth as measured in a scale from zero to one with the Earth Similarity Index, one being identical to Earth.

Comparison of the estimated relative size and orbits of the five exoplanets around Gliese 581. The green shade represent the size of the habitable zone, or the orbital region where an Earth-size planet could have surface liquid water. Planets e, b, and c are too hot for liquid water and life but g and d are in the habitable zone. Planet g is specially in the right spot for Earth-like conditions while d is marginally within these limits, and colder. This is the first case of a stellar system with two potential habitable exoplanets orbiting the same star.

[Red Badger]

Ping!.........

[texson66]

And only 20 light years away!

[cripplecreek]

Good article. Must be the writer has a fair amount of scientific knowledge and didn’t over sensationalize it.

[Bubba_Leroy]

The most “Earth-like” planet ever discovered is named Venus. Similar mass, radius, density and just a little bit closer to the sun than Earth. If only Venus had a magnetic field and a moon it would probably be habitable.

I suspect that most if not all of the “Earth-like” exoplanets are actually “Venus-like” or “Mars-like.”

[jimmygrace]

I have my doubts that any superterrans can foster life. If the planet is too big, most likely the core will be some material other than iron and have little or no magnetic field. No magnetic field means no protection from solar wind which means no atmosphere. I’d like to see an analysis of what size range of planets have the proper gravity to create an iron core.

[ryan71]

“Habitable” in my book means walking around, breathing air not living in a spacecraft and/or wearing a space suit.

Thousands of parameters need to be just right to consider another planet, “habitable”.

Earth is special.

[bigheadfred]

[aimhigh]

I remember hearing years ago, that a 2% deviation in earth’s orbit would render it inhabitable.

[Flavius]

Let’s go

[Alas Babylon!]

Would an orbit only .13 AUs not be tidal locked? Therefore only one side would get constant sunlight, while the other hemisphere would be in constant darkness?

While life could exist on such a world, I think it wouldn’t be Earth-like.

[mrreaganaut]

Let’s talk about the most important thing: Gliese is a terrible name! Who is going to want to explore a system that sounds like a medical condition? I suggest something more marketable, like Chaucer, Laurier, or Gallifrey.