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Astrophysics/Are planets around red dwarf stars habitable?


Do red dwarf type stars have any chances of harboring life bearing planets on their orbits? Because from what I have heard all the planets in the habitable zones would be tidally locked and all life either fried or frozen eventually.


Given red dwarf stars exhibit much lower  surface  temperature (4,000 F vs. 11,000 F for Sun)  one would require any planets to be much closer to arrive within the habitable zone and this is what has been found by the Kepler Space Telescope..  

By way of comparison here: the exoplanet 438 b receives 40 percent more light from its red dwarf star than Earth from its Sun, while Kepler 442 b receives 66 percent of the light (or 33 percent less).  From this it is reckoned that the latter candidate has a 97 % chance of being in the habitable zone and the former a 70 % chance.

SO yes, there is a fair to good chance of red dwarf stars harboring life bearing planets.

Note that this potentiality is not the same as actual tidal locking say in a system in which planets are too close to the central star, or there are two planets in synchronous orbits.

My own take is that red dwarfs are far too problematical - even if potentially feasible - because given their much lower effective temperatures the planets would need to be much nearer. This also suggests the limits of the habitable zone are far more constrained than for a "normal" solar-type star. Hence, the probability of a planet being in it, much lower.

A higher spectral class star, e.g. late F or G, would be far more likely to harbor life -bearing planets in my opinion.  


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Philip A. Stahl


I specialize in stellar and solar astrophysics. Can answer questions pertaining to these areas, including: stellar structure and evolution, HR diagrams, binary systems, collapsars (black holes, neutron stars) stellar atmospheres and the spectroscopic analysis of stars as well as the magnetohydrodynamics of sunspots and solar flares. Sorry No homework problems done or research projects! I will provide hints on solutions. No nonsense questions accepted, i.e. pertaining to astrology, or 'UFOs' or overly speculative questions: 'traveling through or near black holes, worm holes, time travel etc. Absolutely NO questions based on the twaddle at this Canadian site: purporting to show a "new physics". Do not waste my time or yours by wasting bandwidith with reference to such bunkum.


Have constructed computerized stellar models; MHD research. Gave workshops in astrophysics (stellar spectroscopy, analysis) at Harry Bayley Observatory, Barbados. More than twenty years spent in solar physics research, including discovery of SID flares. Developed first ever consistent magnetic arcade model for solar flares incorporating energy dissipation and accumulation. Developed first ever loop-based solar flare model using double layers and incorporating cavity resonators. (Paper presented at Joint AGU/AAS Meeting in Baltimore, MD, May 1994)

American Astronomical Society (Solar physics and Dynamical astronomy divisions), American Geophysical Union, American Mathematical Society, Intertel.

Papers appearing in Solar Physics, Journal of the Royal Astronomical Society of Canada, Journal of the Barbados Astronomical Society, Meudon Solar Flare Proceedings (Meudon, France). Books: 'Fundamentals of Solar Physics', 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level', 'Astronomy & Astrophysics: Notes, Problems and Solutions', 'Modern Physics: Notes, Problems and Solutions'

B.A. degree in Astronomy; M.Phil. degree in Physics - specializing in solar physics.

Awards and Honors
Postgraduate research award- Barbados government; Studentship Award in Solar Physics - American Astronomical Society. Barbados Astronomical Society award for service (1977-91) as Journal editor.

Past/Present Clients
Caribbean Examinations Council (as advisor, examiner), Barbados Astronomical Society (as Journal Editor 1977-91), Trinidad & Tobago Astronomical Society (as consultant on courses, methods of instruction, and guest speaker).

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