Clementine

 1994-004A

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Formally known as the Deep Space Program Science Experiment (DSPSE), the Ballistic Missile Defense Organization's first space probe was known as Clementine. Lawrence Livermore National Lab (LLNL) provided sensors for this BMDO mission to expose advanced sensors to high radiation dosage; the probe was built by NRL and operated by NRL's Naval Center for Space Technology (NCST).

The probe had a dry mass of 183 kg, with 231 kg of propellant giving a mass of 414 kg after ISA separated. With the kick motor, the ISA and the launch adapter total launch mass was 1687 kg. Clementine was 1.1m in diameter and 1.8m high.

The initial attempt to fire the TTI (Transfer Trajectory Injection) burn on Feb 2 was unsuccessful due to a command error. Success came a day later, and the Star 37FM solid motor placed Clementine on the first leg of a stunted phasing loop trajectory. An engineering burn of the bipropellant engine was carried out to clear the fuel lines in preparation for a calibration burn, later cancelled because of delays in jettisoning the interstage just prior to first apogee. Two perigee burns of the engine were used to raise the apogee to lunar distance, and on Feb 19 the spacecraft executed the LOI-1 burn to enter lunar orbit. A second LOI burn to refine the orbit was aborted when telemetry incorrectly showed that the door protecting the delicate sensors was open; the LOI-2 burn was successfully carried out the following day and Clementine began its mapping of the Moon. A number of manuevers were made to ensure complete mapping coverage.

After its successful lunar mapping mission, Clementine departed lunar orbit on May 3. At perigee on May 7, a software failure caused all the attitude control propellant to be depleted. The original plan had called for Clementine to depart Earth orbit with a lunar flyby on May 27 and head off to fly past the minor planet (1620) Geographos on 1994 Aug 30, with a possible further flyby of (3221) Verenia on 1995 Oct 21. This plan was now impossible, and managers decided to try and keep Clementine in Earth orbit. The main propulsion fuel was unaffected by the failure, and it was realized that by using the sun sensor to tell the instant Clementine was pointing in the right direction as it spun on its axis once a second, and pulsing the engine at exactly those times, limited control of Clementine's orbit was possible. Two leading edge lunar swingbys could place Clementine in a 12000 x 240000 km orbit. On May 27 Clementine made its first lunar swingby, at a distance of 8900 km, and fell back toward perigee. The perigee burn on May 31 was only partially successful and a followup trim burn was also insufficient. Then, on June 4, the spacecraft started losing electrical power and its signal became too weak to track. On June 24 the probe passed by the Moon again (at a distance of around 10000-20000 km?) and finally on Jul 20 an 8200 km flyby sent the probe into heliocentric orbit. Contact was recovered briefly in May 1995.

Clementine
Date	Time	Event	Orbit
1994 Jan 25	1634	Launch by Titan 2G
1994 Jan 25	1636	Titan Stage 1 sep T+2:30
	1637?	Fairing sep
	1639?	Titan stage 2 MECO
	1639?	Titan stage 2 sep	259 x 296 x 67
1994 Jan 26	0000		251 x 287 x 66.96
1994 Jan 29	0000		247 x 285 x 66.96
1994 Feb 3	0000		244 x 285 x 66.96
1994 Feb 3	0610	Spinup	250 x 290 x 66.97
1994 Feb 3	0629	TTI burn, Star 37, 2960 m/s	51.2h 252 x 126728 x 66.42
1994 Feb 3	1859		284 x 126962 x 66.48
1994 Feb 3	1900	BPE engineering burn, 3.5 m/s	284 x 126962 x 66.48
1994 Feb 4	0800??	ISA separation near apogee	292 x 126938 x 66.48
1994 Feb 4		Apogee 1
1994 Feb 5	1000	Approach P1	289 x 126259 x 66.36
1994 Feb 5	1001	P1 burn, 213 m/s	413 x 364015 x 66.36
1994 Feb 6	0100	Pass EL1:4
1994 Feb 6	0959	Approach P1C	437 x 367462 x 66.31
1994 Feb 6	1000	P1C burn 31.9 m/s	437 x 367464 x 66.31
1994 Feb 7		Titan stage 2 exploded
1994 Feb 11	s	Apogee 2	385673 km?
1994 Feb 15	1252		855 x 390389 x 63.04
1994 Feb 15	1253	P2 burn, 7.4 m/s	856 x 385388 x 63.04
1994 Feb 16	1259		843 x 410558 x 63.25
1994 Feb 16	1300	P2C burn 1.4 m/s	860 x 409800 x 63.25
1994 Feb 17	0959		793 x 410158 x 64.25
1994 Feb 18	2040?	Enter lunar sphere
1994 Feb 19	1251	LOI approach	404 x Infinity x 89.5
1994 Feb 19	1251.32	LOI-1 burn 460.3 m/s
1994 Feb 19	1257.42	LOI-1 cutoff, lunar orbit	LO 401 x 5426 x 89.49
1994 Feb 20	1241	LOI-2 burn 1.2 m/s	402 x 5388 x 89.33 from 402 x 5425 x 89.33
1994 Feb 21	1216	LOI-2 burn, 2nd attempt, 103.5 m/s	397 x 2965 x 89.27
1994 Feb 22	1217	LOI-2 trim, 5.3 m/s	382 x 2971 x 89.32
1994 Mar 11	0600	Pre LOM 1	445 x 2909 x 89.78
1994 Mar 11	0629	LOM 1 burn, 19 m/s	445 x 2909 x 89.78
1994 Mar 26	0221	Apsidal Rot 1 burn, 106 m/s
		Move periselene from 30S to 30N	447 x 2904 x 89.78
	1241	Apsidal Rot 2 burn, 106 m/s	1008 x 3560 x 89.50
1994 Mar 27	1830	Rotation trim, 3.8 m/s	448 x 2905 x 90.06
1994 Apr 11	0629	LOM 2 burn, 8.7 m/s	428 x 2925 x 90.00
1994 May 3	1300		369 x 2984 x 89.76
1994 May 4	0324:15	LOD (Lunar Orbit Departure), 453.3 m/s
1994 May 4	0330		24737 x Infinity x 107.9
1994 May 5	0055	Depart lunar sphere
1994 May 7	1330		68424 x 452909 x 21.36
1994 May 7	1345	Attitude control failure	68429 x 451989 x 21.34
1994 May 8	0556	2P1 Perigee 68408
1994 May 12	0154	Pre Test mv 1	66832 x 453021 x 21.35
1994 May 12	0159	Test mv 1	66963 x 453381 x 21.30
1994 May 13	0030	Pre Test mv 2	66116 x 453547 x 21.30
1994 May 13	0034	Test mv 2	66057 x 451669 x 21.21
1994 May 16	0530	2A1 Apogee 454929 km?
1994 May 18	1300	Pre 2A2 burn	62600 x 451739 x 21.21
1994 May 20	1300	Post 2A2 burn	57261 x 444300 x 21.12
1994 May 24		2A2 Apogee
1994 May 27		Lunar flyby 8900 km
1994 May 31	2057	2A3 burn,	44768 x 388197 x 19.50
1994 May 31		Trim burn
1994 Jun 5		Contact lost
1994 Jun 24		Lunar flyby
1994 Jul 20		Lunar flyby 8200 km
1994 Jul 21		Solar orbit
1995 Feb 20		DSN contact
1995 Mar 1		Solar orbit	1.02 x 1.06 AU x 0.07
1995 Apr 10		Commanded DSPSE
1995 May 4		Fuel dump burn

Payload:

• UV/Vis imager

• HiRes camera (connected to LIDAR)

• LWIR camera

• NIR camera

• Lidar for laser altimetry Nd YAG laser