Mariner 6

  1969-014A

---

The Mariner Mars 69 spacecraft were similar in design to the Mariner C probes. The first to be launched was M69-3, or Mariner F. During test operations at LC36A, the Atlas 5402 first stage of AC-19 was damaged and had to be replaced by Atlas 5105. M69-3 was swapped to AC-20 to save time.

Launch was at 0129:02 on 1969 Feb 25 by Atlas Centaur from Cape Kennedy's LC36. The single Centaur burn, direct ascent trajectory with an initial azimuth of 108 deg and a yaw burn to final heading of 133 deg, and led to solar orbit insertion at 0141 and Centaur separation at 0143. Centaur venting placed the final stage on a trajectory missing Mars by 637000 km. After a single course correction on 1969 Mar 1, Mariner VI flew past Mars at 0519 on 1969 Jul 31. The flyby was targeted for the equatorial Meridiani Sinus region, with varied light and dark albedo features.

Mariner 6
Date	Time	Event	Orbit
1969 Feb 25	0129:02	Launch by Atlas Centaur
	0131:33	BECO
	0131:36	Booster sep
	0132:18	Centaur insulation sep, 4 panels
	0132:54	Fairing sep
	0133:33	SECO
	0133:40	Atlas sep
	0133:49	Centaur MES
	0141:11	Centaur MECO, solar orbit	90 x Inf x 43
	0142:43	Centaur sep
	0146:45	Solar panels deployed
	0155:24	Centaur venting
1969 Mar 1	0054:44E	TCM 5s 3.1m/s
1969 Mar 3?		Solar orbit
1969 Mar 6	1911	Unlock scan platform; dV 0.01m/s
1969 Apr 28		Canopus lock problems
1969 May 3		Canopus reacquired
1969 Jul 29	0450	Far encounter begins
1969 Jul 29?		AC-20 flyby Mars 640000 km?
1969 Jul 30	0700	In Mars sphere
1969 Jul 31	0222	Near encounter
1969 Jul 31	0519:04	Mars flyby at 3429 km
	0927	End near encounter
1969 Aug 1	0335	Leave Mars sphere
	0546:15	Cruise mode
1969 Aug 7	1612	Resume playback mode
1969 Aug 11		UVS astronomy obs begins
1969 Nov 1		Begin extended mission
1970 Dec		Last contact
1974 Jan		Mars close approach 10Mkm?

Payload:

• TV camera

• IR spectrometer

• UV spectrometer

• IR radiometer, 8-12 mu, 18-25 mu. with 0.025m refracting telescopes