S-45A

S-45A

An S-45 satellite before launch
Mission type	Ionospheric
Operator	NASA
Mission duration	Failed to orbit
Spacecraft properties
Launch mass	33.6 kilograms (74 lb)
Start of mission
Launch date	24 May 1961, 19:48:05 UTC
Rocket	Juno II AM-19G
Launch site	Cape Canaveral LC-26B
Orbital parameters
Reference system	Geocentric
Regime	Highly elliptical (planned)

S-45A was an American satellite, which was lost in a launch failure in 1961. The satellite was intended to operate in a highly elliptical orbit, from which it was to have provided data on the shape of the ionosphere,^[1] and on the Earth's magnetic field.^[2] It was part of the Explorer programme, and would have been designated Explorer 12 had it reached orbit. It was the second of two identical satellites to be launched; the first, S-45, had also been lost in a launch failure, earlier in the year.^[2]

S-45A was launched aboard a Juno II rocket, serial number AM-19G. It was the final flight of the Juno II.^[3] The launch took place from Launch Complex 26B at the Cape Canaveral Air Force Station at 19:48:05 UTC on 24 May 1961.^[3] The system which was intended to ignite the second stage malfunctioned, and as a result that stage failed to ignite.^[4] The rocket failed to achieve orbit.^[5]

References

1. "Explorer S45A". NSSDC Master Catalog. NASA. Retrieved 14 July 2010.
2. Wade, Mark. "P-14". Encyclopedia Astronautica. Retrieved 14 July 2010.
3. McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 14 July 2010.
4. Krebs, Gunter. "Explorer: S-45". Gunter's Space Page. Retrieved 14 July 2010.
5. "Explorer Program". Mission and Spacecraft Library. NASA. Retrieved 14 July 2010.