Mars Global Surveyor

Chronology

Mission timeline

1. November 7, 1996, 17:00:50 UTC

   Launch

   Launched on a Delta II 7925

   NSSDCA's launch/orbital information page gives the launch date and time as 1996-11-07T17:00:50Z. The master catalog page describes the same vehicle as a Delta 7925, a Delta II Lite launch vehicle with nine strap-on solid-rocket boosters and a Star 48 (PAM-D) third stage.

   Earth
2. September 12, 1997, 01:17 UTC

   Orbit insertion

   Inserted into an elliptical capture orbit after a 10 month cruise

   After a 10 month cruise phase, the Mars Global Surveyor began its Mars orbit-insertion burn at 01:17 UT on 12 September 1997 and entered an elliptical capture orbit. The NSSDCA launch/orbital information table gives 00:37 UTC as the start epoch for its first Mars-orbit element set (261.00 x 54024.50 km, 44.99 hours, 93.260 degrees). This is a 40-minute difference between the reported burn-start time and an orbital-elements epoch; the source does not define these as the same event, so the offset is not treated as a demonstrated disagreement in burn time.

   Mars
3. September 23, 1998

   Milestone

   Aerobraking resumed after a five month hiatus

   One of the solar panels failed to latch properly when it was deployed and subsequently showed unexpected motion and moved past its fully deployed position when aerobraking began, thought to be due to the fracture of a damper arm and subsequent structural damage. A new aerobraking schedule was employed, which involved slower aerobraking putting less pressure on the solar panels through April 1998, at which time an 11.6 hour science phasing orbit with a 171 km periapsis was achieved and aerobraking was halted. After a 5 month hiatus, aerobraking was resumed on 23 September 1998. The launch/orbital information page carries the matching 171.40 x 17836.00 km, 11.64 hour orbit and ends its epoch on the same date.

   Mars
4. February 1999

   Milestone

   Reached the circular polar mapping orbit

   After aerobraking ended in February 1999, MGS was in a 118 minute circular polar science mapping orbit with an index altitude of 378 km. The orbit is sun-synchronous (2 a.m./2 p.m.) and maps over the 2 p.m. crossing from south to north, with a 7 day near-repeat cycle so Mars will be mapped in 26 day cycles. Science mapping began in mid-March 1999.

   Mars
5. January 2001

   Milestone

   Primary mission of one martian year completed

   The primary mission lasted one martian year (687 Earth days) through January, 2001. An extended mission took place until April 2002, and further extensions were added after it.

   Mars
6. November 2, 2006

   Loss of contact

   Last communication after more than nine years in Mars orbit

   NASA/JPL records last communication on 2 November 2006. A NASA review board concluded that the spacecraft appears to have succumbed to battery failure after a complex sequence involving onboard computer memory and ground commands; this is a likely-cause finding, not a directly observed failure mechanism. NASA Science lists 14 November 2006 as the mission-end date; that administrative date is retained separately from the last-communication date.

   Mars

Mission architecture

Vehicles

• Mars Global Surveyor · Orbiter

  Destinations: Mars