On the history and future of cosmic planet formation

摘要: We combine constraints on galaxy formation histories with planet models, yielding the Earth-like and giant of Milky Way Universe as a whole. In Hubble volume (10 13 Mpc 3 ), we expect there to be ∼10 20 planets; our own is expected host 9 10 planets, respectively. Proposed metallicity thresholds for do not significantly affect these numbers. However, dependence planets results in later typical times larger galaxies than planets. The Solar system formed at median age existing Way, consistent past estimates, after 80percent if gas within virialized dark matter haloes continues collapse form stars will over more currently exist. show that this would imply least 92percent chance are only civilization ever have, independent arguments involving Drake equation.