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Earlier quoted context omitted.
Atmospheres are useful, but are they a requirement for calling a planet life-friendly? Life on earth first developed in liquid oceans, not in the atmosphere.
Wouldn't an ocean vaporise somewhat automatically to create an atmosphere of there wasn't one already?
"just 12 light-years away" I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-)
How common are "life-friendly" planets (Let's say: on a ratio of Life-Friendly Planet:Non Life-Friendly Planet)? And is there any way to check if life-friendly planets contain life without actually going there?
We don’t yet know the third factor yet, the percentage of planets capable of supporting life. But we do know about 22% of planets are small enough to possibly be rocky and are within the “habitable zone” of a star.
So a possible answer to your first question is that it’s likely 0-22% of stars have at least one planet capable of supporting life like that on Earth. This doesn’t say anything about moons or asteroids or the probability of life developing on a body that could support it.
> Teegarden’s star is a stellar runt that’s barely 9 percent of the sun’s mass. It’s known as an ultra-cool M dwarf Is it too late to change the name to Tyrion Lannister?
Do these planets have their own moons?
I was under the impression that planets to be life-friendly have to be close to their red dwarf star to a point they'll be tidally locked (one side always light other night), meaning their atmosphere would freeze on the dark side and planet would end up without an atmostphere.
Earlier quoted context omitted.
This was indeed the prevailing wisdom for some time. However, more recent research is somewhat more optimistic. Even an atmosphere 10% as dense as that of earth can circulate heat to the dark side efficiently enough, given the right composition. The night side temperature could be within the parameters required to sustain some form of life. Furthermore, tidal locking is dependent on oceans and atmosphere, and can tak…
"However, more recent research is somewhat more optimistic." I am deeply skeptical of that "recent research", which AFAIK is "computer models, where we have zero capability to verify the computer models against even a single data point". The incentives to keep kicking the computer model until it provides something publishable, with no countervailing force provided by real data to be explained by the model, are just t…
Obviously, one shouldn't blindly accept them without experimental confirmation, but one shouldn't also be wildly pessimistic in believing calculations grounded in three centuries worth of validated equations.
"just 12 light-years away" I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-)
If we had the political will, the Orion design could get people there in, what, 200 years, and that's with '70s technology.