Nimbus-5 was launched in December 1972 and was a research-and-development
satellite designed to serve as a stabilized, earth-oriented platform for
the testing of advanced meteorological sensor systems ... and collecting
meteorological and geological data on a global scale. The polar-orbiting
spacecraft consisted of three major structures: (1) a hollow, ring-shaped
sensor mount, (2) solar paddles, and (3) a control system housing. The solar
paddles and control system housing were connected to the sensor mount by a
truss structure, giving the satellite the appearance of an ocean buoy.
Nimbus-5 was nearly 3.7 m tall, 1.5 m in diameter at the base, and about 3 m
wide with solar paddles extended. The torus-shaped sensor mount, which formed
the satellite base, housed the electronics equipment and battery modules. The
lower surface of the torus provided mounting space for sensors and antennas.
A box-beam structure mounted within the center of the torus provided support
for the larger sensor experiments. Mounted on the control system housing, which
was located on top of the spacecraft, were sun sensors, horizon scanners, and a
command antenna. An advanced attitude-control system permitted the spacecraft
orientation to be controlled to within plus or minus 1 degree in all three axes
(pitch, roll, and yaw).
Primary experiments included a temperature-humidity infrared radiometer (THIR)
for measuring day and night surface and cloudtop temperatures as well as the
water vapor content of the upper atmosphere, electrically scanning microwave
radiometer (ESMR) for mapping the microwave radiation from the earth's surface
and atmosphere, infrared temperature profile radiometer (ITPR) for obtaining
vertical profiles of temperature and moisture, Nimbus E microwave spectrometer
(NEMS) for determining tropospheric temperature profiles, atmospheric water
vapor abundances, and cloud liquid water contents, selective chopper radiometer
(SCR) for observing the global temperature structure of the atmosphere, and a
surface composition mapping radiometer (SCMR) for measuring the differences in
the thermal emission characteristics of the earth's surface.
Taken from the NSSDC System for Information Retrieval and Storage (SIRS). For
more information contact the NSSDC Coordinated Request and User Support Office,
301-286-6695 (NASA Goddard Space Flight Center, Code 933.4, Greenbelt, Maryland
Nimbus-5 User's Guide