Mars Global Surveyor
Mars Global Surveyor is a NASA mission designed to study the planet Mars in depth using various highly useful scientific instruments. The mission was the first in 20 years to successfully reach the red planet. During its first year and a half, it dedicated itself to the aerobraking phase, consisting of acquiring the final orbit by going through the upper layers of the Martian atmosphere and thus slowing down its speed until it reached a suitable orbit. This period was longer than expected, so as not to damage the solar panels excessively. It followed a near-surface polar orbit and from there sent back to Earth the highest-resolution photos from Mars exploration and has returned more data than all previous missions combined.
The ship has the shape of a box measuring 1.7 x 1.17 x 1.17 meters, with two distinct parts; one for instruments and one for propulsion. The solar panels have a wingspan of 3.5 x 1.9m and provide 980W of power for the instruments. The dish has a diameter of 15 dm and an extensible arm of two meters.
The mission was funded by NASA and controlled from the Jet Propulsion Laboratory (JPL) and by Lockheed Martin Astronautics.
The ship
The spacecraft is a rectangular box 1.17 m x 1.17 m x 1.7 m in size, with two modules, one for equipment and one for propulsion. His experiments except for the magnetometer (mounted on the solar panel) are mounted on the equipment module of 1.17 x 1.17 m surface. The propulsion module measures 3.5 x 1.9 m, contains 380 kg of fuel with hydrazine, a main of N2O4 and two 596 N Wil boosters for corrections and orbital insertion. Communications are via a 1.5 m diameter parabolic antenna with a 2 m pole, two low gain antennas with 21.33 kbit/s x transmitter, 2 kbit/s engineering data, and 10 bit/ s auxiliary. Electricity is obtained from two 3.5 x 1.9 m solar panels, mounted on opposite sides of the ship; They provide 980 W of power to the ship, stored in two nickel-hydrogen batteries.
Instruments
- Mars Orbiter Camera (MOC): responsible for taking the high-resolution images of the planet as well as others of lower quality to have an overall view of the atmosphere and climate throughout the planet. The MOC camera is controlled by Malin Space Science Systems (MSSS)
- Thermal Emission Spectrometer (TES): is an interferometer that measures the amount of infrared light emitted by the surface of Mars
- Mars Orbiter Laser Altimeter (MOLA): its mission is to build a topographic map of Mars with a laser beam thrown to the surface
- Radio Science Investigations (RS): measure the variations of the signal sent from Earth to measure gravitational deviations.
- Magnetic Fields Investigation (MAG/ER): magnetometer dedicated to studying the magnetic field of Mars and its intensity.
- Mars Relay: support antenna for other NASA, Japan and ESA missions.
 Front view of the instruments |  Back view of the rest of the equipment |  Road and mission phases |
Earth Observations
This probe observed the Earth-Moon system in 2003, when it showed that our planet also has phases, just like Mercury, Venus and the Moon. The lunar phase is a purely geometric effect that is due to the relative position of the element that illuminates (the Sun), the illuminated and the observer.
The Global Surveyor also detected dark spots in the dunes below the south polar ice cap of Mars, between latitudes 60°-80°. The peculiarity of these spots is that 70% of them recur annually in the same place as the previous year. The spots on the dunes appear at the beginning of each spring and disappear at the beginning of each winter, so a team of scientists from Budapest have proposed that these spots could be of biological origin and of an extremophile nature. The ESA space agency it is also analyzing the phenomenon of these blobs using the Mars Express.
For their part, the designers of the camera aboard the 'Mars Global Surveyor', who obtained the images, estimate that the spots could simply be caused by evaporation and freezing of areas in the ice that they contain mainly carbon dioxide (CO2).
End of mission
On November 5, 2006, the last signal from the probe was received, after informing the ground controllers that it had problems with one of the solar panels. For weeks, NASA tried unsuccessfully to regain contact with the probe, both from the ground and from its Mars Reconnaissance Orbiter probe and also with its Spirit and Opportunity rovers. On November 22, 2006, the probe was given up as lost, thus ending one of NASA's most successful missions to Mars. However, the efforts to recover contact have not been completed; ESA, through its Mars Express probe, could have photographed the probe on December 9, which seems to be spinning out of control. Mars Express tried again to detect Mars Global Surveyor on December 21.[citation needed]
Preliminary research results indicate that in June 2006 software was sent to the probe containing an error in two memory addresses (already occupied by other processes, so they were rewritten). When the solar panels were blocked in November, the battery's radiator, which was supposed to keep it from getting too hot, was mistakenly turned towards the Sun, causing the battery to overheat and render it unusable. The probe would have gone into failsafe mode, but without a battery, it would be unable to contact Earth.[citation needed]