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Astronomers Find An Earth-Size World Just 11 Light Years Away (arstechnica.com)
Astronomers have discovered a planet 35 percent more massive than Earth in orbit around a red dwarf star just 11 light years from the Sun. "The planet, Ross 128 b, likely exists at the edge of the small, relatively faint star's habitable zone even though it is 20 times closer to its star than the Earth is to the Sun," reports Ars Technica. "The study in the journal Astronomy & Astrophysics finds the best estimate for its surface temperature is between -60 degrees Celsius and 20 degrees Celsius." From the report: This is not the closest Earth-size world that could potentially harbor liquid water on its surface -- that title is held by Proxima Centauri b, which is less than 4.3 light years away from Earth and located in the star system closest to the Sun. Even so, due to a variety of factors, Ross 128 b is tied for fourth on a list of potentially most habitable exoplanets, with an Earth Similarity Index value of 0.86. In the new research, astronomers discuss another reason to believe that life might be more likely to exist on Ross 128 b. That's because its parent star, Ross 128, is a relatively quiet red dwarf star, producing fewer stellar flares than most other, similar-sized stars such as Proxima Centauri. Such flares may well sterilize any life that might develop on such a world.
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The paper gives the planet's orbital period as 9.9 days. I don't know the maths, but I assume the closer a small body is to a large one the quicker it becomes tidally locked . What impact would tidal locking have on the habitability of the planet?
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Oxygen may be easy to detect, but we have found oxygen also on other planets. And even though it is very rare that there is an abundance of oxygen, even enough to have some left over after everything that could react with it (which is, well, pretty much everything) has, it's far from impossible and as far as I know it's also not easy to determine whether that oxygen is elementary or part of some oxide compound.
But there is one molecule that exists on our planet and only on our planet, and we have not found a single one anywhere else: Chlorophyll. Which is also the foundation of multicellular life on our planet, and since we only know life on this one, it is basically (if we ignore a few methane breathing bacteria) the foundation of any form of higher life.
And it can also be rather easily detected, chlorophyll absorbs light in two rather narrowly defined bands. You find a planet with oxygen that absorbs heavily in the 680-700nm wavelength range? Time to align your large listening dishes!
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The authors of the paper use measurements of the host star's optical spectrum to infer that it doesn't produce a lot of UV emission, and note that it doesn't have frequent optical flares. That's good news for the habitability of the planet around it, as they point out.
However, they apparently did not note that Ross 128 is a relatively strong X-ray source, as measurements by the ROSAT X-ray satellite show. A colleague of mine worked out the X-ray luminosity of the host star, and it turns out to be not unlike that of the Sun, or even larger. That means that the X-ray flux striking the planet -- which is very close to this host star -- is likely high enough to remove the atmosphere of the planet. No atmosphere means not so interesting a planet, alas.
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I would go on a limb and say it is 65 trillion miles away.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.