Nimbus 5 (also called Nimbus E or Nimbus V) was a

meteorological satellite A weather satellite or meteorological satellite is a type of Earth observation satellite that is primarily used to monitor the weather and climate of the Earth. Satellites are mainly of two types: polar orbiting (covering the entire Earth asyn ...

for the research and development of sensing technology. It was the fifth successful launch in a series of the

Nimbus program The Nimbus satellites were second-generation U.S. robotic spacecraft launched between 1964 and 1978 used for meteorology, meteorological research and development. The spacecraft were designed to serve as stabilized, Earth-oriented platforms fo ...

. The objective of Nimbus 5 was to test and evaluate advanced sensing technology, and to provide improved photographs of cloud formations.

Launch

Nimbus 5 was launched on December 11, 1972, by a

Delta Delta commonly refers to: * Delta (letter) (Δ or δ), the fourth letter of the Greek alphabet * D (NATO phonetic alphabet: "Delta"), the fourth letter in the Latin alphabet * River delta, at a river mouth * Delta Air Lines, a major US carrier ...

rocket from

Vandenberg Air Force Base Vandenberg may refer to: * Vandenberg (surname), including a list of people with the name * USNS ''General Hoyt S. Vandenberg'' (T-AGM-10), transport ship in the United States Navy, sank as an artificial reef in Key West, Florida * Vandenberg S ...

in California. The satellite orbited the

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

once every 107 minutes, at an inclination of 99°. Its

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

was and its

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

was .

Instruments

There were six science instruments aboard Nimbus 5. The satellite also included

Sun sensor A Sun sensor is a navigational instrument used by spacecraft to detect the position of the Sun. Sun sensors are used for Spacecraft attitude control, attitude control, solar array pointing, gyroscope, gyro updating, and safe mode (spacecraft), fai ...

s, and horizon scanners for navigation.

Infrared Temperature Profile Radiometer (ITPR)

The ITPR was designed to obtain vertical profiles of temperature and moisture in the atmosphere. A 3-dimensional map could then be created with a resolution of .

Selective Chopper Radiometer (SCR)

The SCR had three objectives: to observe the global atmospheric temperature structure, to observe the distribution of water vapor, and to measure the density of ice crystals in cirrus clouds. Its sensing resolution was about .

Nimbus E Microwave Spectrometer (NEMS)

NEMS was used to demonstrate the use of

microwave Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves. Its wavelength ranges from about one meter to one millimeter, corresponding to frequency, frequencies between 300&n ...

sensors for measuring

tropospheric The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the planetary s ...

temperature profiles, water content in clouds, and surface temperature. The instrument monitored five selected frequencies continuously. The data were recorded on a magnetic tape so they could be transmitted later.

Electrically Scanning Microwave Radiometer (ESMR)

ESMR was used for mapping the microwave radiation from Earth's surface. This information was used to measure the water content of clouds, and to observe sea ice. It was also used to test the use of microwaves to measure soil moisture. The antenna system was deployed after launch, and controlled by an onboard computer.

Surface Composition Mapping Radiometer (SCMR)

For measuring the thermal emission characteristics of Earth's surface and sea temperatures. A scanning mirror rotated ten times per second to sense sections wide. SCMR malfunctioned soon after launch.

Temperature/Humidity Infrared Radiometer (THIR)

THIR was used for measuring cloud top temperatures and water vapor content in the

stratosphere The stratosphere () is the second-lowest layer of the atmosphere of Earth, located above the troposphere and below the mesosphere. The stratosphere is composed of stratified temperature zones, with the warmer layers of air located higher ...

. It could measure cloud temperatures in the day and at night. The sensing unit was a

bolometer A bolometer is a device for measuring radiant heat by means of a material having a temperature-dependent electrical resistance. It was invented in 1878 by the American astronomer Samuel Pierpont Langley. Principle of operation A bolometer ...

made from

germanium Germanium is a chemical element; it has Symbol (chemistry), symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid or a nonmetal in the carbon group that is chemically ...

References

Weather satellites of the United States 1972 in spaceflight {{satellite-stub