MESSENGER Gets an Earful January 7, 2003

One of MESSENGER’s first tasks after arriving at NASA Goddard Space Flight
Center last month was acoustic vibration testing, which measures the
spacecraft’s ability to withstand the sound-induced shaking during launch.
Very powerful speakers were set up around the spacecraft in Goddard’s
reverberant acoustic chamber and engineers cranked the volume of a
"rumbling roar" sound past 140 decibels – louder than a rock concert or a
jet engine! As in the mid-December vibration tests, conducted on shake
tables at the Applied Physics Laboratory, MESSENGER came through the
acoustic test unscathed.

In this image from Dec. 28, MESSENGER team members check the spacecraft
after the acoustic test by deploying a solar panel, using the same type of
pyrotechnically triggered separation nuts MESSENGER will use in flight.
Both solar panels as well as the Magnetometer boom were successfully
deployed.

The gold-colored material on the back of the solar panel –
vapor-deposited aluminized Kapton – will protect the panel from heat
radiating off the surface of Mercury during the science orbit. The Kapton
also will keep the panel cool in case its backside inadvertently points
toward the Sun.