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Satellite characteristics

Launch Date - End 27 June 1978 - 10 October 1978

Status Decommissioned

Orbit type Polar near circular orbit

Altitude 799

Orbit inclination 108

Orbit period 101

Satellite family: NASA-JPL Missions

In the late 1970s, JPL engineers and scientists realized that the sensors they were developing for interplanetary missions could be turned upon Earth itself to better understand our home planet. This has led to a series of highly successful Earth-monitoring missions that have evolved into a major segment of the Laboratory’s activities, now sponsored by NASA’s Science Mission

In 1978, JPL built an experimental satellite called Seasat to test a variety of oceanographic sensors including imaging radar, altimeters, radiometers and scatterometers. Many of the later Earth-monitoring instruments developed at JPL owe their legacy to the Seasat mission.

QuikScat was launched in 1999 and was carrying a scatterometer called SeaWinds that collected data until 2010.

Sensor characteristics

Sensor name ALT (Radar Altimeter)
Sensor short description

ALT was a Ku-band compressed pulse radar altimeter. Objective: Determination of sea surface profiles, currents, wind speeds and wave heights (first attempt to achieve 10 cm altitude precision from orbit).

Sensor type Radar altimeter
Resolution class NA
Swath width (at nadir) 2 km
Sensor name SAR (Synthetic Aperture Radar) Seasat
Sensor short description

The Seasat SAR sensor is regarded as the first imaging SAR system used in Earth orbit. A SAR antenna is mounted on the S/C with its boresight oriented at 20º from the vertical direction (look angle), pointing to the right of the flight path.

Sensor type Imaging microwave radar
Resolution class High (5 - 30 m)
Swath width (at nadir) 100 km
Max look angle 20°
Sensor name SASS (Seasat-A Scatterometer System)
Sensor short description
Sensor type Scatterometer
Resolution class NA
Swath width (at nadir) 500 km
Sensor name SMMR (Scanning Multichannel Microwave Radiometer)
Sensor short description

SMMR is a multispectral, dual-polarization microwave radiometer observing in K-band (~0.75cm to ~2.5cm), X-band (~2.5cm to ~4.0cm) and C-band (~4.0cm to ~8.0cm).

Sensor type Imaging radiometer (passive microwave)
Resolution class Very Low (> 1 km)
Spatial resolution 22 km to 120 km
Spectral bandwidth 6.6 GHZ (45.4 mm) 10.7 GHz (28 mm) 18.0 GHz (16.6 mm) 21.0 GHz (14.2 mm) 37.0 GHz (8.1 mm)
Swath width (at nadir) 600 km
Max look angle 42°
Sensor name VIRR (Visible and Infrared Radiometer)
Sensor short description
Sensor type Imaging radiometer (Vis/IR)
Resolution class Very Low (> 1 km)