Discoverer 19


Discoverer 19, also known as RM-1, was an American satellite which was launched in 1960. It was a technology demonstration spacecraft, based on an Agena-B.[1]

Discoverer 19
Mission typeTechnology
OperatorUS Air Force/ARPA
Harvard designation1960 Tau 1
COSPAR ID1960-019A Edit this at Wikidata
SATCAT no.00068Edit this on Wikidata
Spacecraft properties
Launch mass1,060 kilograms (2,340 lb)
Start of mission
Launch date20 December 1960, 20:32 (1960-12-20UTC20:32Z) UTC
RocketThor DM-21 Agena-B 258
Launch siteVandenberg LC-75-3-5
End of mission
Decay date23 January 1961 (1961-01-24)
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee altitude206 kilometers (128 mi)
Apogee altitude578 kilometers (359 mi)
Inclination83.4 degrees
Period92.4 minutes
← Midas 2
RM-2 →
The launch of Discoverer 19

The launch of Discoverer 19 occurred at 20:32 UTC on 20 December 1960. 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 1960 Tau 1.

Discoverer 19 was operated in a low Earth orbit, with a perigee of 206 kilometres (128 mi), an apogee of 578 kilometres (359 mi), 83.4 degrees of inclination, and a period of 92.4 minutes.[3] The satellite had a mass of 1,060 kilograms (2,340 lb),[4] and was used to demonstrate technology for the Midas programme,[5] including infrared sensors.[4] Communication with the satellite was lost on Christmas Day 1960. It remained in orbit until 23 January 1961,[3] when it decayed and reentered the atmosphere.


  1. ^ Krebs, Gunter. "RM 1, 2 (Discoverer 19, 21)". Gunter's Space Page. Retrieved 30 June 2010.
  2. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 30 June 2010.
  3. ^ a b McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 30 June 2010.
  4. ^ a b Wade, Mark. "Midas". Encyclopedia Astronautica. Archived from the original on 20 November 2010. Retrieved 30 June 2010.
  5. ^ "Discoverer 19". NSSDC Master Catalog. NASA. Retrieved 30 June 2010.