Mystery Mars haze baffles scientists (BBC)
By Rebecca Morelle
Science Correspondent, BBC News
A mysterious haze high above Mars has left scientists scratching their heads.
The vast plume was initially spotted by amateur astronomers in 2012, and appeared twice before vanishing.
Scientists have now analysed the images and say that say the formation, stretching for more than 1,000km, is larger than any seen before.
Writing in the journal Nature, the researchers believe the plume could be a large cloud or an exceptionally bright aurora.
However, they are unsure how these could have formed in the thin upper reaches of the Martian atmosphere.
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more: http://www.bbc.com/news/science-environment-31491805
= new reply since forum marked as read
On their 4 wheelers stirring up that red dirt! 
Despite the fact that Mars no longer has an internal dynamo capable of generating a large global magnetic field as on Earth, there is evidence to suggest that Mars may once have had such a dynamo. This is mainly supported by observations from the American satellite mission MGS (Mars Global Surveyor), which from 1997 to 2006 measured the magnetic field of Mars using a small magnetometer from an altitude of 100-400 km above the planet’s surface. These measurements showed the existence of powerful magnetic crustal fields on the planet’s surface, far more powerful than those found on Earth.
The presence of these crustal fields gives rise to local mini-magnetospheres, i.e. small areas where the lines of the magnetic field locally protect the planet surface from electrically charged particles. Mini-magnetospheres occur when a magnetic field line is connected to two different points on the Martian surface, thus creating a kind of bubble. Between these ‘bubbles’, one end of the magnetic field lines can be connected to the planet and the other to the interplanetary magnetic field (IMF).
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http://www.space.dtu.dk/english/Research/Universe_and_Solar_System/magnetic_field
