The UV limits of life on extrasolar planets: an experiment with halophile archaeabacteria at different UV doses.

ABREVAYA, X.C.; ADAMO, H.P.; CORTÓN, E.; MAUAS, P.J.D.

BOLETÍN DE LA ASOCIACIÓN ARGENTINA DE ASTRONOMÍA

AAA

Año: 2008 vol. 51 p. 1 - 4

1669-9521

Terrestial-type planets around M stars are proposed as feasibleplaces for development of life as we know it. Nevertheless many dMestars emit large amounts of UV radiation during flares and it is unknownif these events could be deleterious for life. Since terrestrial biological systemsare particularly vulnerable to this kind of radiation, this fact couldset a limit for habitability. Organisms as halophile archaeabacteria werefound in ancient evaporites on Earth. Evaporites have been detected inMartian meteorites, so these organisms are proposed as plausible inhabitantsof Mars-like planets or other extrasolar planets. We examine theeffect of UV-C on the halophile archaea Natrialba magadii. Results showthat these organisms are able to survive at the UV doses tested.