MESSENGER Mission News September 24, 2003 – A High-Tech Rain Coa

Spacecraft designers usually have to worry about solar storms,
micrometeorites and extreme temperatures. Last week the MESSENGER
team prepared to protect the spacecraft from an entirely different
sort of storm – Hurricane Isabel.

The team was at work several days before Isabel even came ashore,
clearing loose items from the roof of the Applied Physics Laboratory’s
Kershner Space Building; checking the lightning-protection system of
pointed wires that cover the roof; testing and fueling the building’s
emergency generators; and checking drains to make sure rain water
wouldn’t back up into MESSENGER’s clean room. Finally, as then-Tropical
Storm Isabel approached Maryland on September 18, the team placed a
scrim cloth cover over MESSENGER to protect against potential drips
from above and unplugged its connections to outside power sources – just
to make sure a lightning surge wouldn’t reach the spacecraft’s
electronics.

Fortunately, the APL facility suffered no storm damage and the "
rain coat" was not needed. The MESSENGER team was back to work on
the spacecraft by 7 a.m. on September 19.

MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and
Ranging) is a scientific investigation of the planet Mercury, and
the first NASA mission designed to orbit the planet closest to the
Sun. Dr. Sean C. Solomon, of the Carnegie Institution of Washington,
leads the mission as principal investigator. The Johns Hopkins
University Applied Physics Laboratory in Laurel, Md., is building
and will operate the MESSENGER spacecraft and manages the Discovery-
class mission for NASA.