The galactic habitable zone and the age distribution of complex life in the Milky Way.
Science
; 303(5654): 59-62, 2004 Jan 02.
Article
em En
| MEDLINE
| ID: mdl-14704421
ABSTRACT
We modeled the evolution of the Milky Way Galaxy to trace the distribution in space and time of four prerequisites for complex life the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological evolution, and an environment free of life-extinguishing supernovae. We identified the Galactic habitable zone (GHZ) as an annular region between 7 and 9 kiloparsecs from the Galactic center that widens with time and is composed of stars that formed between 8 and 4 billion years ago. This GHZ yields an age distribution for the complex life that may inhabit our Galaxy. We found that 75% of the stars in the GHZ are older than the Sun.
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Base de dados:
MEDLINE
Assunto principal:
Astronomia
/
Exobiologia
Idioma:
En
Ano de publicação:
2004
Tipo de documento:
Article