Mercury/Magnetosphere

Protective sphere around Mercury due to its magnetic field about the size of the Earth. It varies considerably depending on where Mercury is on its orbit and solar activity. This variance leads to variable protection of molecules in its exosphere and causes them to vary. Stronger on the northern hemisphere than the southern one. Its boundary is the Magnetopause. It is rather leaky, magnetic tornadoes offer paths for solar wind to directly impact the surface.

Web Pages

 * http://en.wikipedia.org/wiki/Mercury_(planet)#Magnetic_field_and_magnetosphere

Magnetosphere Radically Different on 2nd Flyby than First (May 2009)

 * See Mercury/Magnetosphere, Mercury/Magnetopause


 * http://www.nasa.gov/mission_pages/messenger/multimedia/release_telecon_20090430.html