Magnetic Properties of Mars
This composite image shows
particles adhering to magnetic target arrays on the Pathfinder lander. Each array consists
of five magnets that increase in magnetic filed strength as seen from left to right. The
red material forming a bulls-eye pattern on the arrays is magnetic Martian dust deposited
from the atmosphere. An increase in magnetic dust deposition from Sol 10 to Sol 66 is
clearly evident. By analyzing the patterns of dust on the various magnets, scientists are
able to measure the dusts' magnetic strength and infer its composition.
The upper two
images show the lower magnetic properties targets on sols 6 and 13. The lower image shows
the upper magnetic target on sol 26. It is clear that the patterns of dust have developed
with time.
The Mars Pathfinder Magnetic Properties Experiment primarily involves
an array of permanent magnets on the lander. The magnets are assembled to produce a
bulls-eye pattern of attracted dust using an outer annular ring magnet, 18mm in diameter,
surrounding a central cylindrical magnet. In each of two magnet arrays, five such magnets
of progressively increasing strength, are mounted in magnesium blocks.
These magnets are intended to attract any magnetic particles in the windborne dust. The picture shows a magnet array on Sol 6 and on Sol 13. Dust has clearly accumulated on the two strongest magnets. As more dust is attracted with time, we expect the patterns on the magnets to become clearer.