MESSENGER Mission News: Eyeing The Field

The tool designed to answer key questions about Mercury’s magnetic field —
the MESSENGER Magnetometer instrument — is coming together on the spacecraft.
Last week the spacecraft team installed and tested the electronics box for
MESSENGER’s Magnetometer – a necessary step before the team can
install the instrument itself. Eventually the Magnetometer sensor will be
mounted on a 3.6-meter (nearly 12-foot) boom that will keep it away from the
spacecraft’s magnetic field. In this view the Magnetometer electronics box is
on the bottom of the spacecraft, close to where the engineers can be seen in
the lower left.

Mercury’s magnetic field (at the surface of the planet) is about 1,000 times
weaker than Earth’s. The Magnetometer will characterize Mercury’s magnetic
field in detail from orbit over four Mercurial years — each 88 Earth days –
helping scientists determine the field’s exact strength and how that strength
varies with position and altitude. This will provide crucial clues to
help us determine the internal source of Mercury’s magnetic field.