WMAP

 2001-027A

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The Microwave Anisotropy Probe is a MIDEX mission launched by Delta 7425-10 to the Earth-Sun L2 point. 3 month transit to L2 with lunar flybys.

The satellite observes from 22 to 90 GHz with a resolution of 13-55 arcmin. Mass 837 kg full, incuding 72 kg prop.

Box 3.8 h 2.0w? 5.0 span with a circular deployable solar array/thermal shield panel. GSFC mission and GSFC-built spacecraft. The instrument was built in collaboration with Princeton.

A slight SES-1 overburn was required to achieve the desired parking orbit.

In Feb 2003 MAP was renamed WMAP, the Wilkinson Microwave Anisotropy Probe, after David T. Wilkinson (1935-2002), one of the leaders of the COBE and MAP satellite programs. The WMAP team announced their preliminary results at the same time, with values of the Hubble Constant, the age of the universe, the breakdown of baryonic matter, dark matter and dark energy, and the first measurement of the time of reionization.

Close passes (less than 10 million km) to the Earth are predicted in Apr 2025 and Nov 2039.

MAP
Date	Time	Event	Orbit
2001 Jun 30	1946:46	Launch by Delta 7425-10	CC SLC17B
		T+1:03 SRM 1-4 burnout
		T+1:08 SRM 1-4 sep 22 km	-6320 x 28 ?
		T+4:24 MECO
		T+4:30 Stage 1 sep
		T+4:37 SES-1 113 km	-4470 x 160 ?
		T+4:58 Fairing sep 125 km 5.4 km/s	-4400 x 160 ?
		T+5:48	-4189 x 159
		T+7:52	-3426 x 167
		T+10:16	-1767 x 170
		T+10:30	-1482 x 170
		T+10:58	-926 x 169
		T+11:08	-741 x 169
		T+11:24	-370 x 169
	1958:29	T+11:43 SECO-1 (7s late)	167 x 204 x 28.75
	2004	Solar array deploy
	2104:29	T+1:17:43 SES-2
	2104:33	T+1:17:47 SECO-2	181 x 308 x 28.8
	2105:26	T+1:18:40 Stage 2 sep
	2108:03	T+1:19:17 TES
	2108:31	T+1:20:45 TECO
	2112:13	T+1:25:27 Yo-yo despin
	2112:18	T+1:25:32 Stage 3 sep	182 x 290991
	2127s	SES-3 depletion	201 x 325 x 26.9
2001 Jun 30			181 x 289038 x 28.7
2001 Jul 1			182 x 292492 x 28.7
	1308	Pass EL1:4
2001 Jul 2		Apogee 1
2001 Jul 3	2214	Pass 96479 km from the Moon
2001 Jul 4	1322	A1 Cal burn, 0.8kg 105s 1.9m/s	1017 x 299475 x 28.7
2001 Jul 7		Delta stage 2 reentry
2001 Jul 8	0433	Perigee 1 burn TCM 1275s 20.2m/s
2001 Jul 8			3100 x 347000 x 28.3
2001 Jul 12	1611	A2 cal burn 40s 0.2m/s at 347891 km
2001 Jul 17	0336	Perigee 2, TCM 176s 2.5m/s at 2955 km
2001 Jul 18			3002 x 354103 x 28.3
2001 Jul 21	1854	A3 cal burn 40s 0.3m/s 356012 km
2001 Jul 25			4720 x 355851 x 28.8
2001 Jul 26	1229	Perigee 3, TCM 546s 7.4m/s 4741km
2001 Jul 27	0430	P3C, TCM 23.8s 0.3m/s at 158306 km
2001 Jul 29	2011	Enter Lunar sphere
2001 Jul 30	1637	Lunar flyby 5279 km
2001 Jul 31	1257	Depart Lunar sphere
2001 Aug 1			182832 x 1178307 x 28.1
2001 Aug 6	1637	MCC1 17.8s 0.1m/s at 755736 km
2001 Aug 9		Begin science data collection
2001 Aug 13			213681 x 1175513 x 28.1
2001 Aug 21			203451 x 1262240 x 29.25
2001 Aug 26		Within 1.2Mkm
2001 Aug 28			239618 x 1333433 x 30.85
2001 Sep 14	1551	MCC2 6.6s 0.04m/s at 1402107 km
2001 Sep 29			270609 x 1468691 x 40.28
2001 Oct 1		Arrive L2
2001 Oct 10			258144 x 1479888 x 42.22
2001 Nov 2			306445 x 1495753 x 38.15
2001 Dec 13			327623 x 1453870 x 30.87
2002 Jan 4			418706 x 1444582 x 32.19
2002 Jan 8			385538 x 1440816 x 32.80
2002 Jan 15			357519 x 1441727 x 33.02
2002 Jan 16	1650	SK1 72s 0.4m/s
2002 May 8	1603	SK2 53s 0.34m/s
2002 Jul 30	1638	SK3 72s 0.5m/s
2002 Nov 5	1921	SK4 96s 0.56m/s
2003 Mar 12	1350	SK5 50s 0.3m/s
2003 Nov 12	1511	SK6 42s 0.25m/s
2004 Mar 9	1524	SK7 112s 0.66m/s
2010 Aug 14		end of science ops
2010 Aug 19		end of calibration ops
2010 Sep 8		To heliocentric orbit , 20 min burn
2010 Sep 30	1540	Departure burn
	1640:55	End burn
2010 Oct 19	2020	Begin final burn
	2124	Complete burn, 27.7m/s
2012 Jan			1.002 x 1.090 AU x 0.15
2013 Jan			1.001 x 1.085 AU x 0.15

Payload:

• Dual Gregorian 1.4 x 1.6m reflectors

• Differential microwave radiometers 22, 30, 40, 60 and 90 GHz