This figure shows a comparison of images of the sodium emission in the
tail region of Mercury during MESSENGER’s first and second Mercury flybys.
The sodium emission was less symmetric during flyby 1 (see PIA11076), with
a larger region of emission in the north relative to the south, in
contrast to the pattern of sodium emission observed during flyby 2 (see
PIA11402). During the orbital phase of the mission, the MASCS instrument
will regularly measure emissions from atoms and molecules.
Mapping the distributions of species on a daily basis, in conjunction with
the information provided by the other instruments on MESSENGER, will
constrain the processes that generate and maintain the exosphere as well
as provide information on the composition of the surface from which the
exospheric species originate.
Date Acquired: January 14 and October 6, 2008
Instrument: Mercury Atmospheric and Surface Composition Spectrometer (MASCS)
These images are from MESSENGER, a NASA Discovery mission to conduct the
first orbital study of the innermost planet, Mercury. For information
regarding the use of images, see the MESSENGER image use policy.
