Mars Global Surveyor

The Mars Global Surveyor (MGS) launched on November 7, 1996 and arrived in Mars orbit on September 11, 1997. Equipped with scientific instruments, the 1061 kg $154 million US craft is to produce a topographical map of Mars, and identify surface composition. Initially, the mapping mission was to begin in March 1998, but a malfunction in one of the two solar panels (not fully deployed) caused aerobraking to be done at a much slower pace. The craft needs to go from a 48-hour to a 2-hour polar orbit (380 km). Its mapping mission will being in March 1999.

Surveyor is about 1.9 x 1.4 metres in dimension. The materials used to build Surveyor are about the same as Pathfinder's Instrument Electronics Assemblies. It relays information back to Earth at around 43 bits/second.

On March 27, MGS suspended aerobraking to have a month of scientific operations. MGS is now in an elliptical orbit, can take pictures of the surface at an even closer distance than when the orbit circularizes. Imaging targets consisted of the Mars Pathfinder, Viking 1 and 2 landing sites, and the Cydonia region (where the "Face on Mars" is located). All of the targets except Viking 2 -- due to cloud cover -- were photographed. The main reason for imaging the Cydonia region was because of the 2-decade long dispute of the "Face on Mars." The Face of Cydonia, imaged by Viking, showed features on the Martian surface of a face. Controversy about whether the face was alien-made or a product of nature arose. When MGS imaged the area once more, the face was indiscernible. So, the mystery was solved. The "Face on Mars" is just a trick of angle lighting. Scientific operations ended on April 27.

Science Instruments

The science instruments of MGS consist of three major and two minor instruments:

TES (Thermal Emission Spectrometer) will find the composition of the Martian surface.

MOC (Mars Orbiter Camera) was initially put into the Mars Observer spacecraft that failed right before Mars orbit insertion. The spare camera has now been put into MGS to image the surface and the weather patterns. It consists of a wide and narrow-angle lens.

MOLA (laser altimeter) sends a laser onto Mars and measures how long it takes for it to get back to the craft. In this way, it will find out the height of geological features.

The two magnetometers placed each on a solar panel will detect any magnetic field the planet has.

The Relay Antenna will relay data from the lander missions NASA plans to send.