March 6 , 
1996

Jim Sahli
Goddard Space Flight Center
Greenbelt, Md.   20771
(Phone:  301-286-0697)

Polar Status Report #2

	After 12 days on orbit, NASA's newest space physics 
laboratory continues to perform very well!  Polar was launched 
successfully from Vandenberg AFB in California at 6:24 a.m. 
EST Feb. 24. on a Delta II rocket and is in an elliptical polar 
orbit.

	"As of Day 12, we have raised perigee using on-board 
propulsion and powered on all but two of the Polar 
instruments.  Mission operations continue to hum right along 
on schedule," said Dr. Bob Hoffman, who is the Polar Project 
Scientist at the NASA Goddard Space Flight Center in 
Greenbelt, Md.

	"We expect to power on the remaining instruments this 
week and ramp up the high voltages on all the instruments by 
Day 31 into the flight.  We will be ready to begin normal 
science operations a week later.  Also this week we have 
started deploying the long wire antennas and successfully 
deployed the six meter lanyard booms.  Next week, the 
Goddard flight operations engineers will uncage the despun
platform.  This platform will point the three imaging 
instruments at the Earth," said Hoffman.

	Polar is the latest spacecraft in NASA's Global Geospace 
Science mission series, which is part of the International 
Solar-Terrestrial Physics program. Polar and a sister 
spacecraft, Wind, are slated to 
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perform simultaneous, coordinated measurements of key 
regions of 
Earth's space environment.  Included are observations of entry 
and transport of solar plasma over Earth's magnetic poles, 
imaging of the northern aurora (Northern lights) and 
investigations of solar wind properties.  Wind was launched in 
November 1994.

	The Polar spacecraft carrying 11 instruments is 
currently in a elliptical orbit with an apogee of 32,000 statute 
miles and a perigee of 3,200 statute miles on a polar path 
inclined 86 degrees from the equator.

	The satellite is a spin-stabilized cylinder-shaped 
spacecraft 7.9 feet in diameter and 6.9 feet high excluding the 
despun platform. Dry weight is 2,200 pounds, with an 
additional 660 pounds of hydrazine propellant for orbit and 
attitude control.  Its design life is three years.

	The 11 instruments on the Polar spacecraft were 
supplied by university and industry teams as well as NASA 
laboratories.  Data from the instruments will be used to study 
a vast range of phenomena from electromagnetic radiation to 
charged particles from very low to relativistic energies.  
Especially important on Polar are the three high resolution 
imagers looking down on the Earth's polar region.  The 
instruments will image at wavelengths from the visible to 
ultraviolet and into the X-ray region.

	Goddard is managing the Polar project for the Office of 
Space Sciences at NASA Headquarters in Washington, D.C.

	Information about the Polar mission and the ISTP are 
available on the Internet at the following  locations:

Polar:    http://www-istp.gsfc.nasa.gov/ISTP/ggs_project.html

ISTP:     http://www-istp.gsfc.nasa.gov/

	Information will be updated on the Goddard Audio News 
Service, 301-286-NEWS(6397), as it becomes available.

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