Mission Timeline:
Mars Odyssey Flight Phases and Significant Dates

To use the Mars Odyssey Gamma-Ray Spectrometer data effectively, it is essential to be familiar with the flight phases of the spacecraft and important mission milestones. The three main phases of the mission are:

Date Phase
April 7, 2001 Launch of the Mars 2001 Odyssey spacecraft from Kennedy Space Center, Florida, U.S.A.
April 7, 2001
through
Oct. 23, 2001
Cruise Phase of the Odyssey mission, the long journey to Mars.
Oct. 24, 2001
through
Feb. 18, 2002
Aerobraking Phase of the Odyssey mission, where the spacecraft uses the thin outer atmosphere of Mars to slow its speed and achieve a stable orbit.
Feb. 19, 2002
through the present
Primary Mapping Phase of the GRS mission.

Important Primary Mapping Phase Dates

It is important to note that from February 19, 2002 through June 1, 2002, the GRS was in Stowed Mapping configuration, with the Gamma Subsystem measuring background signals from the spacecraft before the GS boom was deployed.

Beginning June 5, 2002, and continuing through August, 2004, the spacecraft entered the Deployed Mapping phase, after the Gamma Subsystem boom was fully deployed, separating the GS from the background signals of the spacecraft.


Detailed Listing of Important Odyssey GRS Dates

The GRS Data Node querying software does not include information in output data about which phase of the mission the data was collected in. That information must be determined by the user according to the dates listed by the mission timeline, below:

Event(s) Date(s) Description or Information
Launch April 7, 2001 Launch of the Mars 2001 Odyssey spacecraft and beginning of the Cruise phase.
Cruise Phase Begins April 7, 2001
The cruise phase of the mission is the journey of the spacecraft to Mars, before orbital insertion and aerobraking.
CEB Powered On April 25, 2001 The Central Electronics Box (CEB) is powered on for the first time in flight, during the Cruise Phase.
GS, NS, and HEND are powered on May 2, 2001 The Gamma Subsystem (GS), the Neutron Spectrometer (NS), and the High Energy Neutron Detector (HEND) are powered on for the first time in flight, for testing and calibration en route to Mars.
GS Data collected off and on May 2, 2001
through
Sept. 4, 2001
Gamma Subsystem data is collected off and on during this period for testing and calibration of instruments.
NS and HEND data collected off and on May 2, 2001
through
Sept. 24, 2001
Neutron Spectrometer and Heigh Energy Neutron Detector data are collected intermittently during testing and calibration.
All Instruments Shut Down for MOI Sept. 24, 2001 All instruments on Odyssey are shut down for the Mars Orbit Insertion on September 24, 2001.
Cruise Phase Ends Oct. 23, 2001 The cruise phase of the mission is the journey of the spacecraft to Mars, before orbital insertion and aerobraking.
Aerobraking Maneuvers Begin Oct. 24, 2001 During the aerobraking phase, the spacecraft achieves a stable orbit around Mars.
Data Collection (Short) Oct. 24, 2001
to
Oct. 26, 2001
GS, NS, HEND data collected for 2 days
GRS Shut Down Oct. 26, 2001
through
Nov. 16, 2001
All Gamma Ray Spectrometer Instruments shut down when the spacecraft was put into safe mode.
Data Collection Nov. 16, 2001
through
Dec. 19, 2001
Science data was collected off and on during this period.
GRS Shut Down Dec. 19, 2001
through
Jan. 14, 2001
Science data was collected off and on during this period.
Data Collection Jan. 14, 2002
through
Feb. 18, 2002
Science data was collected off and on during this period, with a short data outage on February 15, 2002. There may be other data gaps during this period due to missing telemetry.
Aerobraking Maneuvers End February 18, 2002 During the aerobraking phase, the spacecraft achieved a stable orbit around Mars.
Primary Mapping Phase Begins Feb. 19, 2002 Primary Mapping phase of the mission began on Feb. 19, 2002, and is expected to continue until August, 2004.
Stowed Mapping Feb. 19, 2002
through
June 1, 2002
By this time the spacecraft has achieved a mapping orbit, and during the Stowed Mapping period the 6-meter Gamma Subsystem boom is not deployed, but still in "stowed" configuration. Data collection during this time includes the background hydrogen signal from the spacecraft.

During the stowed mapping period, two anneals were performed on the gamma detector. During these dates no science data was collected:

March 8, 2002 through March 22, 2002
and
May 6, 2002 through May 20, 2002.
Deployment of GS Boom June 1, 2002
through
June 4, 2002
The GRS was shut down on June 1, 2002 to prepare for the Gamma Subsystem Boom deployment, which was performed on June 4, 2002.
Deployed Mapping Phase June 5, 2002
through
August, 2004
The Deployed Mapping Phase is the primary scientific data collection phase of the mission.