Everything continues to go well with MAVEN as it is readied for arrival at Mars on Sunday, September 21st. All spacecraft systems are operating nominally. We had scheduled a final Trajectory Correction Maneuver (TCM-4) for September 12th.

However, the maneuver was cancelled because the flight path did not warrant a correction. MAVEN is right on track.

In the next few days the Mars Orbit Insertion (MOI) sequence will commence on the spacecraft. Most commands will be performed autonomously (without the need for commanding from Earth).

However, there are two ground command opportunities still available to alter the spacecraft's flight path, if necessary, in order to raise altitude for its first pass at Mars.

These altitude raise decisions will be made by the Project at approximately 24 hours and 6 hours prior to MOI, in close coordination with the Navigation team and the Navigation Advisory

Group. Right now we don't expect to need an additional maneuver because of how well the spacecraft is flying.

On Sunday evening, MAVEN will slew (turn) to point the main engines in the direction of travel and fire for about 33 minutes in order to slow down the spacecraft enough to "capture" into Mars orbit.

Although we have direct line of sight of MAVEN during the entire burn sequence, the observed data back on Earth will actually be viewed 12 minutes after the events occur because of the distance between Earth and Mars. For more details, check out this MAVEN MOI video, "Targeting Mars:"