Stacksat (P87-2): POGS, TEX, and SCE

The U.S. military's STACKSAT mission involved the launch of three similar spacecraft, POGS, TEX and SCE. The POGS (Polar Orbiting Geomagnetic Survey) satellite was designed to measure the Earth's magnetic field vector as a function of position. Data from the experiment will be used to improve Earth navigation systems, and is stored in an experimental solid state recorder. TEX (Transceiver EXperiment) carries a variable power transmitter used to study ionospheric effects on RF transmissions. Data from the experiment will be used to determine minimum spacecraft transmitter power levels for transmission to ground receivers. SCE (Selective Communications Experiment) carries a variable frequency transmitter to study ionospheric effects at various RF frequencies, and is also designed to demonstrate message store and forward techniques. Six low cost ground stations were designed, built and located around the world to operate these spacecraft.

Spacecraft
Gravity gradient stabilized. Body mounted solar arrays provide ~15W orbit average power.

Payload
POGS carries a magnetometer to accurately map the Earth's magnetic field for the Defense Mapping Agency. Data is stored in a new Fairchild solid state recorder. TEX and SCE each carry specially designed transmitters to study ionospheric effects on radio signals.

Country of Origin	United States
Customer/User	US Navy (POGS, SCE), USAF (TEX)
Manufacturer(s)	Defense Systems Inc. (now CTA)
Orbit	741 km, incl. = 90 deg.
Design Life	3 years

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
POGS (USA 56 ?)	1990-031A	4/11/90	WSMC	Atlas E
TEX (USA 57 ?)	1990-031B	4/11/90	WSMC	Atlas E
SCE (USA 58 ?)	1990-031C	4/11/90	WSMC	Atlas E