| This
image of Phobos, the inner and larger of the two moons of Mars, was taken
by the Mars Global Surveyor on August 19, 1998. The Thermal Emission Spectrometer
(TES) measured the brightness of thermal radiation at the same time the
camera acquired this image. By analyzing the brightness, TES scientists
could deduce the various fractions of the surface exposed to the Sun and
their temperatures. |
 |
This
preliminary analysis shows that the surface temperature, dependent on slope
and particle size, varies from a high of +25°F (-4°C) on the most
illuminated slopes to -170°F (-112°C) in shadows. This large difference,
and the fact that such differences can be found in close proximity, adds
support to the notion that the surface of Phobos is covered by very small
particles. |
|
