Explorer 45

 1971-096A

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The SSS-A (SSS 1, Small Scientific Satellite 1) payload was a lightweight magnetospheric studies satellite, only 52 kg in mass and 0.69m long, 0.74m diameter, with two 0.8m and one 0.6m booms, as well as two 2.7m electric field booms. The project was managed by NASA Langley and the satellite was built by NASA-GSFC.

Launch was at 0552 by Scout B from the San Marco Platform in the Indian Ocean. It was delivered to a 466.9 min, 233 x 26895 km x 3.6 deg orbit.

SSS 1 operated until 1974 Sep 30, and reportedly reentered on 1992 Jan 10. However, the archival orbital data shows it close to reentry in March 1987.

Data associated with object 5598 issued in Dec 1991 showing it in a 200 x 1200 km orbit are no longer in the archive. This latter data seems likely to be an error and I conclude reentry was in 1987 Mar. The final stage is recorded as entering on 1987 Mar 3, but probably this was the payload. The fourth stage was in rapid decay in May 1979 and probably reentered in 1979 Jun-Jul.

Objects associated with Ex 45
	Date	Orbit
5598 (96A)
	1987 Mar	129 x 572 x 3.7
5973 (96B)	1972 Mar	270 x 26381 x 3.3
	1979 May 27	169 x 9232 x 3.5
5598 (UNK1)	1989 Oct	241 x 18489 x 3.7
5598 (UNK2)	1991 Dec	209 x 1281 x 3.7

An object was cataloged in 1989 Oct in a 241 x 18489 km x 3.7 deg orbit, which reentered in Jun 1992; by late 1991 it had a 5545 km apogee. These elements are also not in the public archive. The object may have been a despin weight from Explorer 45; Longanecker and Hoffman (1973, JGR 78, 4711) give a mass breakdown which includes 0.2 kg for despin weights and cables.

Explorer 45
Date	Time	Event	Orbit
1971 Nov 15	0552:00	Launch by Scout B S163CR	SM
		T+1m St 1 burnout
		T+1:20 St 2 burn
		T+2:40 Fairing sep, 104 km
		T+2:41 Stage 3 burn
		T+3:17? Stage 3 burnout
	0559:16	T+7:16 St 4 burn
	0559:46?	T+7:46? St 4 burnout	466.9 233 x 26895 x 3.6
		T+7:51 Injection
	0604?	Despin
	0605?	St 4 sep
1974 Sep 30		End of ops
1979 Jun?		Stage 4 reentered
1987 Mar 3		reentered
1989 Oct 30		71-96C cataloged
1991 Dec 25		71-96A	206 x 1203 x 3.7
1991 Dec 25		71-96C	244 x 5545 x 3.7
1992 Jan 10		reported reentry date
1992 Jun 26		1971-96C reentered

Payload:

• Aerodynamic heating expts

• Radiation damage

• Data recovery test

• Fluxgate magnetometer

• Search coil magnetometer

• Proton,alpha detector 25-872 keV p

• AC E field detector

• e/p analyser 0.8-25keV

• DC E field detector

• Electron solid state detector 35-400 keV