Are We alone; habitable planets? (Introduction)

by David Turell , Wednesday, March 22, 2017, 17:16 (2802 days ago) @ David Turell

More discussion and scientific reports on Trappist+1 and seven planets. Life unlikely but hope springs eternal:

https://cosmosmagazine.com/space/trappist-1-hopes-for-life-dwindle?utm_source=Today+in+...

"Thus, only the middle planet remains a candidate for hosting life. It could maintain “at least some habitable surface”, Wolf notes, depending on the atmospheric nitrogen levels. If the planet is, in fact, covered in ocean, then “near present day Earth surface temperatures can be maintained”.

"However, even one habitable planet may turn out to be a forlorn hope. Ultracool dwarf stars, Wolf says, may take as long as one billion years to settle into a stable system, during which orbiting planets are exposed to intense solar radiation, producing extreme greenhouse conditions. If this was the case with Trappist-1, then for the middle planet to retain abundant water today it would have to originally held seven times the ocean volume of Earth.

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"Lingham and Loeb contend that because the seven planets in Trappist-1 are very close together – the distance between adjacent ones being far less than the distance between Earth and Mars – then microbial panspermia is likely to be robust.

“'By drawing upon the analogy with the theory of island biogeography, we argued that a large number of species could have ‘immigrated’ from one planet to another, thereby increasing the latter’s biodiversity,” they write.

“'As known from studies on Earth, a higher biodiversity is correlated with greater stability, which bodes well for the multiple members of the Trappist-1 system.'”

Comment: I have idea no what they are smoking. This is a dwarf low heat star with close planets that are probably tidally locked. Anything to find life elsewhere. None so far.