Landsat 2

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Landsat 2
Landsat-1.jpg
Artist's rendering of Landsat 2.
Mission type Earth imaging
Operator NASA / NOAA
COSPAR ID 1975-004A
SATCAT no. 07615
Spacecraft properties
Manufacturer RCA Astro
Launch mass 953 kilograms (2,101 lb)
Start of mission
Launch date January 22, 1975 (1975-01-22)
Rocket Delta 2910
Launch site Vandenberg AFB SLC-2W
Orbital parameters
Reference system Geocentric
Regime Sun-synchronous
Semi-major axis 7,283.0 kilometres (4,525.4 mi)
Eccentricity 0.0008709
Perigee 906.3 kilometers (563.1 mi)
Apogee 919.0 kilometers (571.0 mi)
Inclination 98.9 degrees
Period 103.18 minutes
RAAN 192.8963°
Mean anomaly 345.3381°
Epoch 28 May 2016[1]

Landsat 2 is the second satellite of the Landsat program. The spacecraft originally carried a designation of ERTS-B (Earth Resource Technology Satellite B) but was renamed "Landsat 2" prior to its launch on January 22, 1975. Despite having a design life of one year, Landsat 2 operated for over seven years, finally ceasing operations on February 25, 1982.[2]

Development[edit]

Landsat 2 was manufactured by General Electrics's Space Division in Valley Forge, Pennsylvania.[2] This satellite was considered an experiment, unlike Landsat 1. It was originally designated as ERTS-B (Earth Resources Technology Satellite-B) and was renamed prior to launch.[3] The satellite's design life was for a minimum of one year.[2]

Satellite design[edit]

Operation[edit]

The spacecraft was 3 metres (9.8 ft) tall with a 1.5 metres (4.9 ft) diameter. Two solar panel arrays that were 4 metres (13 ft) long each each, with single axis articulation, generated power for the spacecraft. Landsat 2 had a liftoff weight of 953 kilograms (2,101 lb).[2]

The attitude was controlled with three hydrazine thrusters. The satellite transmitted data back to the ground with S-Band and Very High Frequency (VHF) transmitters, at a rate of 15 Mbps and 6 bit quantization. The satellite had three-axis fine attitude control with four wheels, which gave it +/- 0.7 degrees of control.[2]

Sensors[edit]

As in the case of its predecessor Landsat 1, the satellite's payload included two remote sensing instruments, the Return Beam Vidicon (RBV) and the Multi-Spectral Scanner (MSS). The specifications for these instruments were identical to those of the instruments carried on Landsat 1. This was not the case for Landsat 3, which added a short-lived thermal band to the MSS instrument. The data acquired by the MSS was considered more scientifically useful than the data returned from the RBV, which was rarely used and considered only for engineering evaluation purposes.[4]

Mission[edit]

Launch[edit]

Landsat 2 was launched January 22, 1975 on a Delta 2910 at Vandenberg Air Force Base in California.[3] The satellite was placed in a sun-synchronous, near-polar orbit with an inclination of 99.2 degrees and an altitude of 917 kilometres (570 mi). Landsat 2 circled Earth every 103 minutes, totaling 14 times per day. The orbital cycle was repeated every 18 days.[2]

Operations[edit]

It operated until February 25, 1982, when it was removed from operations due to a faulty yaw control thruster.[3] The satellite was placed in standby mode on March 31, 1983.[2]

References[edit]

  1. ^ "LANDSAT 2 Satellite details". N2YO. Retrieved 28 May 2016. 
  2. ^ a b c d e f g United States Geological Survey (2006-08-09). "Landsat 2 History". Retrieved 2007-01-16. 
  3. ^ a b c "Landsat 2". NASA Landsat Science. Retrieved March 26, 2017. 
  4. ^ "40+ Years of Earth Science: Landsat 2". National Aeronautics and Space Administration. July 12, 2005. Retrieved January 16, 2007.