Mars does not have much in the way of an atmosphere – or a magnetic field. It is being suggested its protective shield was switched off half a billion years ago by an asteroid strike (see www.dailygalaxy.com November 3rd). The Mars Global Surveyor sent back data in 2009 that seemed to indicate something like that occurred – using computer simulation modelling techniques.
NASAs Fermi Gamma-ray Space Telescope has discovered enormous 'gamma ray bubbles' at the centre of the Milky Way (see also www.dailygalaxy.com November 3rd and www.nasa.gov/home/hqnews/2010/nov/M10-155_Fermi_Telecon.html ). The source of the bubbles is a mystery but they appear to span 65,000 light years from end to end, soaring above the disc of the galaxy. Analysis has ruled out dark matter and ideas are rife – from exploding stars to high speed jets of matter created when stars fell into a giant black hole.
At www.physorg.com/print207896570.html there is news from a high profile Fermilab physics experiment that appears to confirm the existence of a new elementary particle, a fourth kind of neutrino. Its presence however is theoretical rather than actual (see details on site) and is being published in Physical Review Letters (online). It says sterile neutrinos which are basically neutral might help explain the composition of the universe. Physicists and astronomers are looking for sterile neutrinos because they might explain dark matter – and now they think they have found them.