Detalles de publicación
PP 013034
Chemical evolution and the galactic habitable zone of M31 (the Andromeda Galaxy)
(1) IA-UNAM, Mexico, (2) IAC, Spain, (3) ULL, Spain, (4) Kapteyn Instituut, Nederlands
We have computed the Galactic Habitable Zones (GHZs) of the Andromeda
galaxy (M31) based on the probability of terrestrial planet formation, which
depends on the metallicity (Z) of the interstellar medium, and the number of
stars formed per unit surface area. The GHZ was obtained from a chemical
evolution model built to reproduce a metallicity gradient in the galactic disk,
[O/H](r) = -0.015 dex kpc-1 x r(kpc) + 0.44 dex. If we assumed that Earth-
like planets form with a probability law that follows the Z distribution shown
by stars with detected planets the most probable GHZ per pc2 is located
between 3 and 7 kpc for planets with ages between 6 and 7 Gy. But the
highest number of stars with habitable planets is in a ring located between 12
and 14 kpc with mean age of 7 Gy. 11 % and 6.5 % of the all formed stars in
M31 may have planets capable of hosting basic and complex life, respectively.
galaxy (M31) based on the probability of terrestrial planet formation, which
depends on the metallicity (Z) of the interstellar medium, and the number of
stars formed per unit surface area. The GHZ was obtained from a chemical
evolution model built to reproduce a metallicity gradient in the galactic disk,
[O/H](r) = -0.015 dex kpc-1 x r(kpc) + 0.44 dex. If we assumed that Earth-
like planets form with a probability law that follows the Z distribution shown
by stars with detected planets the most probable GHZ per pc2 is located
between 3 and 7 kpc for planets with ages between 6 and 7 Gy. But the
highest number of stars with habitable planets is in a ring located between 12
and 14 kpc with mean age of 7 Gy. 11 % and 6.5 % of the all formed stars in
M31 may have planets capable of hosting basic and complex life, respectively.