Discoverer 26

Discoverer 26, also known as Corona 9019, was an American optical reconnaissance satellite which was launched in 1961. It was the sixth of ten Corona KH-2 satellites, based on the Agena-B.^[1]

Discoverer 26

Mission type	Optical reconnaissance
Operator	US Air Force/NRO
Harvard designation	1961 Pi 1
COSPAR ID	1961-016A
SATCAT no.	00160
Mission duration	2 days
Spacecraft properties
Spacecraft type	Corona KH-2
Bus	Agena-B
Manufacturer	Lockheed
Launch mass	1,150 kilograms (2,540 lb)
Start of mission
Launch date	7 July 1961, 23:29:48 (1961-07-07UTC23:29:48Z) UTC
Rocket	Thor DM-21 Agena-B 308
Launch site	Vandenberg LC-75-3-5
End of mission
Decay date	5 December 1961 (1961-12-06)
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee altitude	229 kilometers (142 mi)
Apogee altitude	713 kilometers (443 mi)
Inclination	82.9 degrees
Period	94 minutes
Discoverer ← Discoverer 25 Discoverer 27 → KH-2 Series ← Discoverer 25 (KH-2 5) Discoverer 28 (KH-2 7) →

The launch of Discoverer 26

The launch of Discoverer 26 occurred at 23:29:48 UTC on 7 July 1961. A Thor DM-21 Agena-B rocket was used, flying from Launch Complex 75-3-5 at the Vandenberg Air Force Base.^[2] Upon successfully reaching orbit, it was assigned the Harvard designation 1961 Pi 1.

Discoverer 26 was operated in a low Earth orbit, with a perigee of 229 kilometres (142 mi), an apogee of 713 kilometres (443 mi), 82.9 degrees of inclination, and a period of 94 minutes.^[3] The satellite had a mass of 1,150 kilograms (2,540 lb),^[4] and was equipped with a panoramic camera with a focal length of 61 centimetres (24 in), which had a maximum resolution of 7.6 metres (25 ft).^[5] Images were recorded onto 70-millimeter (2.8 in) film, and returned in a Satellite Recovery Vehicle, which was deorbited two days after launch. The Satellite Recovery Vehicle used by Discoverer 26 was SRV-511. Once its images had been returned, Discoverer 26's mission was complete, and it remained in orbit until it decayed on 5 December 1961.^[3]