Nimbus
type: Concept

Nimbus-4
change note: 2019-03-26 17:35:45.0 [sritz] update WeightedRelation (Platform-Instrument); update WeightedRelation (1);
change note: 2019-03-26 17:35:02.0 [sritz] update Resource (image); insert WeightedRelation (id: null related concept uuid: 7bf9f69e-3bc7-45ad-9224-969676d36d78 relationship type: null relationship value: null generated by: null);
change note: 2015-05-12 12:54:13.0 [saritz] update PrefLabel (Nimbus-4);
in scheme: platforms
definition: Nimbus-4 was launched in April 1970 and was the fourth in a series of second-generation meteorological research-and-development satellites that was designed to serve as a stabilized, earth-oriented platform for the testing of advanced meteorological sensor systems and for collecting meteorological data. The polar-orbiting spacecraft consisted of three major structures: (1) a ring-shaped sensor mount, (2) solar paddles, and (3) the control system housing. The solar paddles and the control system were connected to the sensor mount by a truss structure, giving the satellite the appearance of an ocean buoy. Nimbus-4 was nearly 3.7 m tall, 1.45 m in diameter at the base, and about 3 m across 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 ring provided mounting space for sensors and telemetry antennas. An H-frame structure mounted within the center of the torus provided support for the larger experiments and tape recorders. Mounted on the control system housing, which was on top of the spacecraft, were sun sensors, horizon scanners, gas nozzles for attitude control, and a command antenna. Use of an advanced attitude-control subsystem permitted the spacecraft's orientation to be controlled to within plus or minus 1 degree for all three axes (pitch, roll, and yaw). Primary experiments consisted of an image dissector camera system for providing daytime cloudcover pictures both in real-time and recorded modes, temperature-humidity infrared radiometer (THIR) for measuring daytime and nighttime surface and cloudtop temperatures as well as the water vapor content of the upper atmosphere, infrared interferometer spectrometer (IRIS) for measuring the emission spectra of the earth/atmosphere system, satellite infrared spectrometer (SIRS) for determining the vertical profiles of temperature and water vapor in the atmosphere, a monitor of ultraviolet sola…
type: Concept