USA-85

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USA-85
Navstar-2.jpg
A Block IIA GPS satellite
Mission type Navigation
Operator US Air Force
COSPAR ID 1992-079A[1]
SATCAT № 22231[1]
Mission duration 7.5 years (planned)[2]
Spacecraft properties
Spacecraft type GPS Block IIA[2]
Manufacturer Rockwell[2]
Launch mass 1,816 kilograms (4,004 lb)[2]
Start of mission
Launch date 22 November 1992, 23:54:00 (1992-11-22UTC23:54Z) UTC
Rocket Delta II 7925-9.5, D216[3]
Launch site Cape Canaveral LC-17A[3]
End of mission
Deactivated 17 March 2008 (2008-03-18)
Orbital parameters
Reference system Geocentric
Regime Medium Earth
(Semi-synchronous)
Perigee 20,074 kilometres (12,473 mi)[4]
Apogee 20,290 kilometres (12,610 mi)[4]
Inclination 54.8 degrees[4]
Period 717.96 minutes[4]

USA-85, also known as GPS IIA-7, GPS II-16 and GPS SVN-32, was an American navigation satellite which formed part of the Global Positioning System. It was the seventh of nineteen Block IIA GPS satellites to be launched.

USA-85 was launched at 23:54:00 UTC on 22 November 1992, atop a Delta II carrier rocket, flight number D216, flying in the 7925-9.5 configuration.[3] The launch took place from Launch Complex 17A at the Cape Canaveral Air Force Station,[5] and placed USA-85 into a transfer orbit. The satellite raised itself into medium Earth orbit using a Star-37XFP apogee motor.[2]

On 23 December 1992, USA-85 was in an orbit with a perigee of 20,074 kilometres (12,473 mi), an apogee of 20,290 kilometres (12,610 mi), a period of 717.96 minutes, and 54.8 degrees of inclination to the equator.[4] It was intended to broadcast signal PRN 32, but this was changed to PRN 01 on 28 January 1993 after it was discovered that receivers could not track the PRN 32 signal. The spacecraft was operated in slot 4 of plane F of the GPS constellation,[6] and had a mass of 1,816 kilograms (4,004 lb). It had a design life of 7.5 years,[2] and was retired from service on 17 March 2008. It is unclear whether it has been retained as a backup satellite.

References[edit]

  1. ^ a b "Navstar 2A-07". US National Space Science Data Center. Retrieved 10 July 2012. 
  2. ^ a b c d e f Krebs, Gunter. "GPS-2A (Navstar-2A)". Gunter's Space Page. Retrieved 10 July 2012. 
  3. ^ a b c McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 10 July 2012. 
  4. ^ a b c d e McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 10 July 2012. 
  5. ^ McDowell, Jonathan. "Launch List". Launch Vehicle Database. Jonathan's Space Page. Retrieved 10 July 2012. 
  6. ^ Wade, Mark. "Navstar". Encyclopedia Astronautica. Retrieved 10 July 2012.