SOLRAD 8

Solrad 8
Mission type	Solar science
Operator	NASA
COSPAR ID	1965-093A
SATCAT no.	1738
Mission duration	Unknown
Spacecraft properties
Manufacturer	Naval Research Lab
Launch mass	56.7 kilograms (125 lb)
Start of mission
Launch date	November 19, 1968, 22:11:30 UTC
Rocket	Scout (rocket)
Launch site	Wallops Flight Facility
End of mission
Last contact	August 1967
Decay date	Unknown
Orbital parameters
Reference system	Geocentric
Regime	Circular orbit
Eccentricity	0.01302
Peri altitude	704 kilometers (437 mi)
Apo altitude	891 kilometers (554 mi)
Inclination	59.7 degrees
Period	100.8 minutes
Epoch	19 November 1965, 04:48:00 UTC
	Error: no value specified for required parameter "apsis"

The SOLRAD 8 satellite was one of the SOLRAD program that began in 1960 to provide continuous coverage of solar radiation with a set of standard photometers. SOLRAD 8 was a spin-stabilized satellite oriented with its spin axis perpendicular to the sun-satellite line so that the 14 solar X-ray and ultraviolet photometers pointing radially outward from its equatorial belt viewed the sun on each revolution. Data were transmitted in real time by means of an FM/AM the satellite's telemetry system and were recorded by the stations on the STADAN tracking network. The satellite performed nominally, except for the spin system, which failed to maintain 60 rpm (at spin rates below 10 rpm data reduction became difficult). The spin rate gradually decreased to 4 rpm on September 12, 1966. At that time, ground command succeeded in reactivating spinup to 78 rpm, which exhausted the gas supply. From this point, the spin rate gradually decreased to 10 rpm in August 1967, when data collection was substantially decreased..^[1]