Starless planets may have life

[B5C]

Starless planets may be habitable after all

LIQUID water may survive on free-floating planets that have no star to warm them. If they also support life, they could act as stepping stones to spread life around the galaxy.

Gravitational tussles with other planets or passing stars can eject planets from their solar systems. But even in the cold of space, these wayward worlds could stay warm, thanks to the decay of radioactive elements in their rocky cores.

Dorian Abbot and Eric Switzer of the University of Chicago calculate that rocky planets with a similar mass to Earth could remain warm enough to keep water liquid under thick, insulating ice sheets for over a billion years. A planet with the same fraction of water as Earth could keep a subsurface ocean liquid if it was 3.5 times Earth's mass. But a planet with 10 times Earth's water concentration could do this if it weighed just one-third as much as Earth, they say (arxiv.org/abs/1102.1108).

"It's a really interesting idea," says Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics. "But we would have to land on [a planet] and burrow down to see if life is possible."
http://www.newscientist.com/article/...ef=online-news

If this is true, the number of habitual plants has increased a lot.

[MathiasOfAthens]

prob doesnt increase that much... I could imagine how dark it would be on those worlds.

Besides I didnt even know planets could be starless.

[Gordon Freynman]

"It's a really interesting idea," says Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics. "But we would have to land on [a planet] and burrow down to see if life is possible."

Spoiler Alert, click show to read: 

This would be a pretty good place to start testing the idea I imagine.

[vlach]

well nothing on the surface since that would be most certainly near 2 kelvin

[B5C]

prob doesnt increase that much... I could imagine how dark it would be on those worlds.

Besides I didnt even know planets could be starless.

Yes, they are called "Rouge" Planets.

http://en.wikipedia.org/wiki/Rogue_planet

The possible "Rouge" Planet:
http://en.wikipedia.org/wiki/Cha_110913-773444

[Turtle Hammer]

prob doesnt increase that much... I could imagine how dark it would be on those worlds.

Besides I didnt even know planets could be starless.

Not much darker than the bottom of the sea where they've found things that basicly live off of huffing the gas from volcanic vents. I would say though, that the odds of finding intelligent life haven't increased much though, since tool use sort of needs fire to progress past a certain point.

[Saturn]

In 1998, David J. Stevenson theorized[6] that some planet-sized objects drift in the vast expanses of cold interstellar space and could possibly sustain a thick atmosphere which would not freeze out due to radiative heat loss. He proposes that atmospheres are preserved by the pressure-induced far infrared radiation opacity of a thick hydrogen-containing atmosphere.

It is thought that during planetary system formation, several small protoplanetary bodies may be ejected from the forming system.[7] With the reduced ultraviolet light associated with its increasing distance from the parent star, the planet's predominantly hydrogen and helium containing atmosphere would be easily confined even by an Earth-sized body's gravity.

It is calculated that for an Earth-sized object at a kilobar hydrogen atmospheric pressures in which a convective gas adiabat has formed, geothermal energy from residual core radioisotope decay will be sufficient to heat the surface to temperatures above the melting point of water.[6] Thus, it is proposed that interstellar planetary bodies with extensive liquid water oceans may exist. It is further suggested that these planets are likely to remain geologically active for long periods, providing a geodynamo-created protective magnetosphere and possible sea floor volcanism which could provide an energy source for life.[6] The author admits these bodies will be difficult to detect due to the intrinsically weak thermal microwave radiation emissions emanating from the lower reaches of the atmosphere.

A study of simulated planet ejection scenarios has suggested that around five percent of Earth-sized planets with Moon-sized moons would retain their moons after ejection. A large moon would be a source of significant geological tidal heating.[8]

Doesn't seem entirely new.

[Niles Crane]

Rouge Planets? Habitual planets?

Never heard of them.

[MrMofo]

Rouge Planets? Habitual planets?

Never heard of them.

Be nice.

[Niles Crane]

Be nice.

The fact that he linked to rogue planets and then went on to misspell it twice is unforgivable.

[Angrychris]

have you been huffing gas?