Phoenix

 2007-034A

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The first Mars Scout mission is Phoenix, led by LPL at the University of Arizona. Phoenix SOC will be at Tuscon. Spacecraft is built by Lockheed Martin Astronautics.

Phoenix will land in the north polar region ca. 70N The mission will determine polar climate and weather, and study the role of water and ice on the northern plains. It will carry a robot sampler arm to search for organic molecules. It will use the Mars Surveyor 2001 lander, whose mission was cancelled after the Mars 98 failures. The robot arm can excavate to a depth of 1m.

Launch by Delta II 7925-9.5. Approach Vinf = 3.5 km/s; entry at 5.75 km/s.

Cruise stage (with solar panels), aeroshell, MPL descent system. Operations at new U of Arizona SOC. Lander has 4 RCS and 4 ACS thrusters; they fired through the backshell for cruise operations. 12 landing thrusters each have 31N thrust.

Cruise is 2.64m dia 1.74m high 3.6m span, mass 82 kg.

Lander is 1.8m dia 1m? high disk + 2 panels each 2.0m dia, span 5.5m, total height 2.2m. Launch mass 680 kg. Entry mass 572.7 kg. Mass 524 kg at landing.

Mass budget
Cruise stage	82 kg
Lander cruise prop	25 kg
Back shell	110 kg
Aeroshell	62 kg
Lander dry	343 (363 on surf?)
Lander descent prop	58 kg
Lander descent prop used	38 kg
MP Total		680

Injection at 2255 km, vel 11.0215 km/s, C3 = 29.080, perigee 195.2 km

Planned landing site is 68.35N 233.0E (areocentric), the Green Valley site among the Scandia Colles in Vastitas Borealis. Initial postlanding estimate was 68.22N 234.30E. Pictures of the surface were transmitted via Odyssey one orbit later. Final estimate from MRO is 68.219N 234.248E.

16.9 kg prop left after landing. Parachute 7s later than predicted.

Backshell 90m S of lander, parachute 10m S of backshell.

Heatshield 50m SE of lander.

Phoenix
Date	Time	Event	Orbit
2007 Aug 4	0926:34	Launch by Delta 7925-9.5	CC SLC17A
		T+1:03 SRM 1-6 out
		T+1:05 SRM 7-9 out
		T+1:06 SRM 1-6 sep
		T+2:09 SRM 7-9 out
		T+2:11 SRM 7-9 sep
		T+4:23 MECO
		T+4:31 St 1 sep
	0931:10	T+4:36 SEIG-1
		T+5:03 Fairing sep
	0935:54	T+9:20 SECO-1	166 x 167 x 28.5
	1040:21	T+1:13:47 SEIG-2
	1042:36	T+1:16:02 SECO-2	162 x 5793 x 28.5
	1043:39	T+1:17:05 Stage 2 sep	148.41 163 x 5651 x 28.5
	1044:16	T+1:17:42 TES
	1045:44	T+1:19:10 TECO
	1050:39	T+1:24:05 Yo-yo despin
	1050:44	T+1:24:10 Stage 3 sep
	1054:16	T+1:27:42 Target interface point	195 x -40365 x 28.5
			193 x -40716 x 28.41 (Horizons)
	1718	Pass EL1:4
2007 Aug 6	0830	Leave Earth SOI (0.93Mkm)
2007 Aug 7	1336	Depart Earth sphere 1.5Mkm
		Mars miss distance 950000 km
2007 Aug 10	1830	TCM-1 18.5m/s 3:17
2007 Oct 24		TCM 46s 3m/s
2008 Apr 10		TCM 35s
2008 May 18	0045	TCM-5, 3s burn
2008 May 21	0924	Enter Mars sphere 1.082Mkm
2008 May 23	1345	Enter Mars SOI (0.58Mkm)
2008 May 25	2330?		-22 x -18951 x 69.72
	2323:40s	E-7 min Cruise separation
		E-5min Turn to entry
	2331:13	E-0s Entry 125 km, 5.7 km/s, gamma = -12
		5.6 km/s at -13.01 deg 77.7 az 197.7,69.36 124.5
	2334:50	E+228s Para deploy 13 km
	2335:03	E+236s Heat shield jettison 12 km
		E+261s Radar on
	2335:14	E+246s Leg deployment
	2338	E+405s Lander sep from backshell, 0.9 km
		Backshell Avoidance Manuever
		E+444 Throttle up
		E+465s Radar cutoff
	2338:39	E+446s Reconstructed landing time
	2338:24	E+470s Landing
		L+25min Solar array deploy
2008 Oct 27		Dust storm
2008 Nov 2		Last transmission
2009 May 25		end of ops

Payload:

• MARDI Descent imager (Malin)

• SSI Surface Stereoscopic Imager, Stereo Panoramic cameras (Arizona/Shinohara)

• Mass spectrometer

• RA Robotic arm - Trench digging arm, 2.4m (JPL/Bonitz) with ISAD (Icy Soil Acquisition Device).

• RAC Robotic arm camera (MPI-SolarSystem-Lindau/Arizona/Keller,Smith)

• TEGA Thermal evolved Gas Analyser (Arizona/UTD/Boynton)

• MECA Chemistry-microscopy instrument: (JPL/Hecht) optical and atomic force microscopes, wet chemistry lab for soil analysis

• TECP Electrical and thermal conducivity sensor probe (on arm)

• MET Meteorology lab (CSA,York/Whiteway); zenithal lidar, temperature/pressure station