ORBIT

The DE-1 orbit as it appeared shortly after launch. The spacecraft spin axis is perpendicular to the orbital plane. The argument of perigee advances at a rate of 108 degrees per year, thereby providing excellent coverage of the polar cap, the auroral field lines, and the equatorial region at radial distances extending out to 4.65 Earth radii.

		Initial Orbit Parameters
--------------------------------------------------------	
Parameter	DE-1			DE-2
--------------------------------------------------------
Apogee		3.63 Re			1012 km
Perigee		570 km			309 km
Inclination	89.91 deg		89.99 deg
Period		6 hours 49 min		98 min