Under a Crimson Sun

Prospects for Life in a Red Dwarf System

David S Stevenson, Springer, MultCo 576.839S8474U 2013

A book about the prospects of life on planets around M and L stars.

Spectral class, hot to cold: O B A F G K M L : Oh Be A Fine (Girl/Guy) Kiss My Lips

O through F are very big, bright, and fast burning. Probably evolving too rapidly for intelligent life to emerge.

There are twice as many K stars as G stars, and far more M's and L's - some of the L's may be too difficult to detect, or have not yet ignited in 14 billion years. Are the coldest too unenergetic to power aerobic oxygen-generating photosynthesis?

Less luminous stars last far longer - and planets can orbit closer in. Too close in, and they tide-lock one face towards the star.

Note Added 2019

By 2012, new data changed our understanding of solar system formation and SLR (short lived radionuclides) like ²⁶Al. Supernovae also produce a lot of ⁶⁰Fe (which decays into nickel) and that is nearly absent from Vesta-sourced meteorites. An alternative, championed by Nicolas Daupas of the Origins Laboratory at the University of Chicago, is formation of the solar system inside the shell around a Wolf-Rayet star, perhaps 10 parsecs away. Their 2012 paper describes their meteorite analysis, and their 2017 describes their model of triggered star formation.

CrimsonSun (last edited 2019-10-05 01:06:59 by KeithLofstrom)