Explorer 13

Explorer 13

Explorer 13 (S-55A)
Operator	NASA
Harvard designation	1961 χ1
COSPAR ID	1961-022A
SATCAT no.	180
Website	1961-022A
Mission duration	3 days
Spacecraft properties
Manufacturer	GSFC
Launch mass	86 kg (190 lb)
Start of mission
Launch date	August 25, 1961, 19:26 (1961-08-25UTC19:26) UTC
Rocket	Scout X-1
Launch site	Wallops LA-3
End of mission
Last contact	August 28, 1961 (1961-08-29)
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Eccentricity	0.07392
Perigee altitude	125 km (78 mi)
Apogee altitude	1,164 km (723 mi)
Inclination	37.7°
Period	97.5 minutes
Epoch	August 25, 1961
Instruments
Instruments Cadmium Sulfide Cell Micrometeorite Detector Copper Wire Micrometeroite Detector Pressurized Cell Micrometeorite Detector Impact Detection Grid Detectors
Explorers

Explorer 13 (also called S-55A) was an American satellite launched as part of Explorers program. Was launched on August 25, 1961 from Wallops Flight Facility, Virginia, U.S..

Mission

Explorer 13 was injected into a geocentric orbit of moderate eccentricity using a Scout launch vehicle. The objectives of the flight were to test vehicle performance and guidance and to investigate the nature and effects of micrometeoroids on the spacecraft systems. The scientific instrumentation consisted of cadium sulfide-cell, wire-grid, piezoelectric, pressurized-cell, and foil-type micrometeoroid detectors.

The spacecraft was a 1.93 m × 0.61 m (6.3 ft × 2.0 ft) cylinder. The orbit was lower than planned, and the spacecraft reentered the atmosphere on August 28, 1961, after only slightly more than 2 days in orbit. No penetrations were recorded by this satellite during experiment operations. This aided in determination of useful flux limits for subsequent experiment design.