Aatos KaarneFeb 7, 2023
Mikko Tuomi

A newly discovered #exoplanet could be worth searching for signs of #life.

Despite its close distance to the central #star, the planet Wolf 1069 b receives only about 65% of the incident radiant power of what Earth receives from the sun.

These special conditions make #planets around red dwarf stars like Wolf 1069 potentially friendly to life.

#astronomy #exoplanets
https://phys.org/news/2023-02-astronomers-rare-earth-mass-rocky-planet.html

Paper by Kossakowski et al. (2023):
https://doi.org/10.1051/0004-6361/202245322

Astronomers find rare Earth-mass rocky planet suitable for the search for signs of life

A newly discovered exoplanet could be worth searching for signs of life. Analyses by a team led by astronomer Diana Kossakowski of the Max Planck Institute for Astronomy describe a planet that orbits its home star, the red dwarf Wolf 1069, in the habitable zone.

Phys.org
Feb 4, 2023 at 12:56pmWeb
Show threadReimanSaaraFeb 27, 2023
@mustapipa Two questions:
1) Does not the close proximity to parent star mean, that the planet is dangerously closer to solar eruptions, radiation bursts etc.? Isn't it more difficult to determine size of habitable zone around red dwarves than around yellow dwarves?
Show threadMikko TuomiFeb 27, 2023
@ReimanSaara Yes. And no, we know equally little about general HZ properties for both (all) stellar types.
Show threadReimanSaaraFeb 27, 2023
@mustapipa
2) With small stars whose planets orbit close to the star, planets may have locked orbits. While these planets could still sustain life in their twilight zone in theory, wouldn't a locked orbit be more fatal in practice due to both extreme weather fueled by temperature differences between day and night side + actual size of such zone being very small in case of Earth-sized planets? To me, it would seem that at least evolution of multicellular life would be highly unlikely.
Show threadMikko TuomiFeb 27, 2023

@ReimanSaara Impossible to tell. Habitability can be sustained given suitable atmospheric and/or oceanic circulation, distributing heat more evenly. Surely such planets are still very different from Earth, but inhospitable to life? Who knows.

And tidal locking can produce 3/2 solutions too where, as is the case for Mercury, the planet rotates 3 times over every 2 orbits around the Sun.