Mars Global Surveyor
Mars Orbiter Camera (MOC)

2002 Solar Conjunction Sampler

MGS MOC Releases MOC2-316 to MOC2-319, 8 August 2002

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was turned off on July 31, 2002, and it will remain off until at least August 19, 2002. During this time, Mars is behind the Sun relative to Earth, and communication with the spacecraft is extremely limited (for several days, there will be no communication at all). MOC is off during this time because any images it might acquire could not be transmitted to Earth, and the twice-weekly targeting schedules can not be sent to the spacecraft.

Solar Conjunction is the term used to describe the period when the Sun is between Earth and Mars---from the Earth, Mars appears to move towards, and eventually merge with, the Sun. Solar Conjunction comes around about every 25 months, the first solar conjunction for MGS occurred in May 1998, the second in June/July 2000, the third in August 2002. Each time, the MOC was turned off and safely returned to service after the conjunction period ended.

With the MOC "on vacation," the MOC Operations Team can also take a short breather, having commanded over 125,000 images over the past 4+ years. However, "short" is the operative word, as in a few days the team will be hard at work preparing for the MOC turn-on later in the month. The pictures shown here (click on icons, below) are examples of some of the things the MOC team has been seeing in the past few months leading up to Solar Conjunction, including continued monitoring of mid-latitude gullies, dust devils, and chance observations of unusual landforms.

Meridiani Crater

Newton Gullies

Dust Devil

"Inca City"

Malin Space Science Systems, Inc.