Because this exoplanet orbits very near its sun, one side forever faces that star, and that may well be enough to melt a "bullseye" water body, at the surface. An ocean, about half the size of the Atlantic (since the rocky core is about 5X the size of Earth), warmed to around 68° F. Cozy, for life as we know it, with a nitrogen rich atmosphere.
The fact that it orbits a cooler red dwarf nearby means based on the spectral data, that this system could well have been relatively stable for over 2 billion years. . . enough time, for the random events of evolutionary "proto-biology" to have now organized into single cells. . . or potentially. . . more. Here's the Canadian paper just out, on it all -- and a bit:
. . .When the exoplanet LHS 1140 b was first discovered, astronomers speculated that it might be a mini-Neptune: an essentially gaseous planet, but very small in size compared to Neptune. But after analyzing data from the James Webb Space Telescope (JWST) collected in December 2023 - combined with previous data from other space telescopes such as Spitzer, Hubble and TESS - scientists have come to a very different conclusion.
Located some 48 light-years from Earth in the constellation Cetus, LHS 1140 b appears to be one of the most promising exoplanets in its star's habitable zone, potentially harboring an atmosphere and even an ocean of liquid water. The results of this discovery by Université de Montréal astronomers are available on ArXiv and will soon be published in The Astrophysical Journal Letters. . . .
Estimates based on all accumulated data reveal that LHS 1140 b is less dense than expected for a rocky planet with an Earth-like composition, suggesting that 10 to 20 per cent of its mass may be composed of water. This discovery points to LHS 1140 b being a compelling water world, likely resembling a snowball or ice planet with a potential liquid ocean at the sub-stellar point, the area of the planet’s surface that would always be facing the system’s host star due to the planet’s expected synchronous rotation (much like the Earth’s Moon).
“Of all currently known temperate exoplanets, LHS 1140 b could well be our best bet to one day indirectly confirm liquid water on the surface of an alien world beyond our Solar System,” said Cadieux, lead author of the new study. “This would be a major milestone in the search for potentially habitable exoplanets. . . .”
Now you know. . . onward, to the Ariane 6 launch tonight by ESA, off the coast of South America. . . grinning ear to ear.
नमस्ते
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