Press Release

Mars Global Surveyor Status Report November 11, 1999

By SpaceRef Editor
November 11, 1999
Filed under

Thursday, November 11, 1999 (DOY 308/19:00:00 to DOY 315/19:00:00 UTC)

Launch / Days since Launch = Nov 7, 1996 / 1100 days

Start of Mapping / Days since Start of Mapping = April 1, 1999 / 224 days Last Orbit Covered by this Report = 3032

Total Orbits = 4714

Total Mapping Orbits = 3032

Recent Events:

The mm008 sequence continues executing nominally and will continue execution through November 17. Development of the
mm009 sequence has begun. Work has also begun on the development and validation of the mini-sequences required for MR
commanding in support of the DS2 microprobes mission on December 3. The change approved last week to update the
sampling rate for critical spacecraft telemetry, that will allow us to more fully characterize and ascertain the cause of the
HGA position error counts, has been uplinked to the spacecraft. At this time we have not had a repeat of the event with the
new telemetry in place.

HGA Anomaly:

The HGA inner gimbal angle continues to decrease and is currently at 70.7degrees. The inner gimbal angle will continue
decreasing, reaching the location of the gimbal obstruction at 41.5 deg in early February. Work continues on the design and
implementation of a new mapping data collection and return plan that will maximize the science data return for the
remainder of the nominal mapping mission. The updated mapping command blocks have been generated and will be released
to JPL early next week so they can begin implementing them in the sequencing software. This will support the start of
system level validation in the STL in the next few weeks.

Spacecraft Health:

All other subsystems continue to report nominal status.


There have been 26 uplinks to the spacecraft during the last week, including new star catalogs and ephemeris files, and
instrument command loads. Total command files radiated to the spacecraft since launch is 4082.

Upcoming Events:

1) Validation and uplink of the mm009 sequence November 15.

2) Validation and uplink of the DS2 MR mini-sequences.

SpaceRef staff editor.