MESSENGER Puts on a MASCS June 5, 2003

With several bolts and a few adjustments, MESSENGER team
members at the Johns Hopkins Applied Physics Laboratory
(APL) reached a milestone last weekend when they installed the
first science instrument on NASA’s Mercury-bound spacecraft.

On a busy May 31 in the APL cleanroom facilities in Laurel, Md.,
technicians attached the Mercury Atmospheric and Surface
Composition Spectrometer (MASCS) onto the lower part of the
spacecraft’s structure, inside its Launch Vehicle Adapter ring. At
about 12 inches long, 7 inches tall and 7 inches wide, the
5.5-pound MASCS was designed and built at the Laboratory for
Atmospheric and Space Physics, University of Colorado at Boulder.
The instrument will measure gases in Mercury’s atmosphere and
detect the minerals on the planet’s surface.

Engineers also attached the main electronics unit for MESSENGER’s
Magnetometer; the first of the dual Data Processing Units (DPUs),
which will control the science instruments and feed their data to
the spacecraft; and the frame for MESSENGER’s signature sunshade.

"This is a big step in MESSENGER’s development," says
Dr. Rob Gold, MESSENGER payload manager at APL. "From
the team members who design the instruments to the people on the
ground who install them, there’s a great feeling that comes with
getting that first part of the science payload on the spacecraft.
Now we have six more instruments to go, and we expect things to
come together rather quickly."

Later this week the team is scheduled to connect the DPU and MASCS
to the spacecraft’s main electrical system and install the X-Ray
Spectrometer instrument. Gold adds that all the instruments are
scheduled for integration on the spacecraft by mid-July.