Solar systems with life-bearing planets may be rare if they are dependent on the presence of asteroid belts of just the right mass, according to a study by Rebecca Martin, a NASA Sagan Fellow from the University of Colorado in Boulder, and astronomer Mario Livio of the Space Telescope Science Institute in Baltimore, Md.

They suggest that the size and location of an asteroid belt, shaped by the evolution of the Sun's protoplanetary disk and by the gravitational influence of a nearby giant Jupiter-like planet, may determine whether complex life will evolve on an Earth-like planet. The findings will appear today in the Monthly Notices of the Royal Astronomical Society: Letters (published by Oxford University Press).

http://hubblesite.org/news_release/news/2012-44