 Explorer 9 before launch | |
| Names | S-56A Explorer IX NASA S-56A |
|---|---|
| Mission type | Air density research |
| Operator | NASA |
| Harvard designation | 1961 Delta 1 |
| COSPAR ID | 1961-004A |
| SATCAT no. | 00081 |
| Mission duration | 3 years (achieved) |
| Spacecraft properties | |
| Spacecraft | Explorer IX |
| Spacecraft type | Air Density Explorer |
| Bus | S-56 |
| Manufacturer | Langley Research Center |
| Launch mass | 7 kg (15 lb) |
| Dimensions | 3.66 m (12.0 ft) diameter |
| Power | solar cells and rechargeable batteries |
| Start of mission | |
| Launch date | 16 February 1961, 13:05:00 GMT |
| Rocket | Scout X-1 (ST-4) |
| Launch site | Wallops Flight Facility, LA-3 |
| Contractor | Vought |
| Entered service | 16 February 1961 |
| End of mission | |
| Decay date | 9 April 1964 |
| Orbital parameters | |
| Reference system | Geocentric orbit[1] |
| Regime | Medium Earth orbit |
| Perigee altitude | 545 km (339 mi) |
| Apogee altitude | 2,225 km (1,383 mi) |
| Inclination | 38.91° |
| Period | 118.6 minutes |
| Instruments | |
| Satellite Drag Atmospheric Density | |
Explorer Program | |
Explorer 9, known as S-56A before launch, was a NASA satellite which was launched in February 1961 to study the density and composition of the upper thermosphere and lower exosphere.[2] It was a reflight of the failed Explorer S-56 mission, and consisted of a 7 kg (15 lb), 3.66 m (12.0 ft) balloon which was deployed into a medium Earth orbit.[3] The mission was conducted by NASA's Langley Research Center.
- ^ Cite error: The named reference
Displaywas invoked but never defined (see the help page). - ^ Smith, Woody. "Explorer Spacecraft Series". NASA. Retrieved 17 June 2010.
This article incorporates text from this source, which is in the public domain.
- ^ Wade, Mark. "S-56". Encyclopedia Astronautica. Archived from the original on 28 October 2002. Retrieved 17 June 2010.
