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Asteroid Belts Of Just The Right Size Are Friendly To Life

November 5, 2012 Leave a comment

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.

This might sound surprising because asteroids are considered a nuisance due to their potential to impact the Earth and trigger mass extinctions. But an emerging view proposes that asteroid collisions with planets may provide a boost to the birth and evolution of complex life. Asteroids may have delivered water and organic compounds to the early Earth. According to the theory of punctuated equilibrium, occasional asteroid impacts might accelerate the rate of biological evolution by disrupting a planet’s environment to the point where species must try new adaptation strategies.

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2012-345
Also: http://hubblesite.org/newscenter/archive/releases/2012/44/full/
Also: http://www.ras.org.uk/news-and-press/219-news-2012/2183-asteroid-belts-of-just-the-right-size-are-friendly-to-life

NASA Astrobiologists Find Iron’s Role In Life On Early Earth


When life began on Earth, iron may have done the job of magnesium, making life possible.

On the periodic table of the elements, iron and magnesium are far apart. But new evidence discovered by the NASA Astrobiology Institute (NAI) team at the Georgia Institute of Technology suggests that three billion years ago, iron did the job magnesium does today in helping Ribonucleic acid (RNA), a molecule essential for life, assume the molecular shapes necessary for biology.

Full Story: http://www.nasa.gov/centers/ames/news/releases/2012/12-44AR.html
Additional Story: http://astrobiology.nasa.gov/articles/finding-iron-s-role-in-life-on-early-earth/