Galaxy may swarm with 100,000 times more ‘nomad planets’ than stars
February 24, 2012
There may be 100,000 times more wandering “nomad planets” in the Milky Way than stars, and some may carry bacterial life, according to a new study by researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC).
If any of these nomad planets are big enough to have a thick atmosphere, they could have trapped enough heat for bacterial life to exist,” said Louis Strigari, leader of the team that reported the result in a paper submitted to the Monthly Notices of the Royal Astronomical Society.
Last year, researchers detected about a dozen nomad planets, using a technique called gravitational microlensing.
A confirmation of the estimate could lend credence to another possibility mentioned in the paper — that as nomad planets roam their starry pastures, collisions could scatter their microbial flocks to seed life elsewhere.
KIPAC is a joint institute of Stanford University and the SLAC National Accelerator Laboratory.
Ref.: Louis E. Strigari, et al., Nomads of the Galaxy, 12 Jan 2012, ArXiv, http://arxiv.org/abs/1201.2687
Ref.: Jack Singal, Nomadic Planets May Swarm the Galaxy, Tidbits from 2012, Kavli Institute for Particle Astrophysics and Cosmology, 22 Feb 2012.