Seasat

 1978-064A

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Seasat was built by Lockheed and based on the Agena D satellite. While Spacecraft Agena D satellites launched on Atlas D and Atlas SLV-3 boosters were considered to be part of the Atlas Agena D launch vehicle, Seasat's Agena D was considered to be a payload, launched by an Atlas F. The Seasat mission used a 120 inch diameter fairing from LMSC (larger than the standard Convair 84 inch Agena fairing). SAMSO 6595ATW at Vandenberg provided the launch services, and SAMSO provided the Atlas F. LeRC was responsible for the Atlas from the NASA side, with JPL responsible for the Agena and payload.

The Atlas F launch came at 0112 UT on 1978 Jun 27. The Atlas 23F sustainer engine cut off at T+4:45. The Atlas separated at T+5:08 and the Agena coasted until T+6:23 when it ignited for its first burn. Main engine cutoff came at T+10:14, with Seasat in an elliptical transfer orbit. At T+55:48, the Agena reignited, burning until T+57:34. Seasat 1 was now in a 773 x 803 km x 108.0 deg orbit. In October transmissions from Seasat were suddenly cut short by an electrical short circuit.

The radar altimeter had a 3 ns pulse time and operated at 13.5 GHz, with a nadir swath of 2-12 km and determined altitude and wave heights. The SAR was 20 deg off-nadir and had a swath of 100 km, with a spatial resolution of 25m. The scatterometer determined surface winds to 2 m/s. The VIRR, derived from the ITOS SR, provided cloud and temperature data. The SMMR provided sea surface temperature, sea ice mapping and surface winds.

Seasat 1
Date	Time	Event	Orbit
1978 Jun 27	0112	Launch by Atlas F
		T+2:09 BECO
		T+2:12 Booster sep
		T+3:27 Fairing
	0116	Sustainer cutoff (T+4:45)
		T+5:03 VECO
	0117	Atlas sep (T+5:08)
	0118	Agena MES-1 (T+6:25)
	0122	Agena MECO-1 T+10:14	185 x 784 x 108.0
	0209:28	T+57:15s MES-2
	0209:34	T+57:21s MECO-2
			773 x 803 x 108.0
1978 Aug 26		Rev 863, orbit adjust burn
1978 Oct 10	0312:02	Power failure