Timothy Birdnow

An atmosphere has apparently been discovered around an exoplanet similar to the Earth's and in the liquid water band, thus presenting the possibility of life as we know it.

The planet - LhS 1140 b - orbits a red dwarf star (class M) about 45 light years away, so relatively close in astronomical terms.

The article doesn't tell us more than about the star which is important. As the article observes red dwarf stars are poor places for Earth'like worlds in that they put out a lot of x rays and have strong solar winds which usually strip atmospheres off of planets in the liquid water band, which with a red dwarf is very clos

But what kind of class M star is it? They do vary in terms of size and radiative output.

Also the article just says it's an "Earth-like world" but doesn't give details on it's size relative to the Earth. Is it smaller or larger? That too can make a difference.

Such a world would almost certainly be tidally locked, like the Moon is around the Earth, so only one side of the planet would face the star.

At any rate they determined the atmosphere is primarily helium (which is a surprised; Helium is a light gas and would easily be stripped away from the world) and Helium, of course, can be breathed in place of nitrogen, meaning we could possibly actually walk outside on it (at least with protective clothing to avoid the radiation or on the night side. But the planet probably has hurricane winds if it's tidal locked, and that would be a problem. Life would be difficult on the surface. But if it has an ocean...

I rather suspect a helium atmosphere would mean a superearth, a planet comfortably larger than Earth. I should think a planet as small as ours would be stripped of it's atmosphere.

Proxima Centauri - the nearest star to ours - has a super-Earth planet that is denuded of it's atmosphere in close orbit around that red dwarf star.

At any rate this is of academic interest only; we won't be going there any time soon, not with our current technology and not with any technology we can conceive of at present. Contrary to popular fiction warp drive is an impossibility and probably always will be. You are talking about bending space in the manner of a black hole.

But it's fun to think about. And who knows; maybe eventually we'll send a probe there, and maybe a multi-generational ship. But that will be a long, long time off.

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