Mars Express

From Wikipedia, the free encyclopedia

This article documents a current spaceflight.
Information may change rapidly as the mission progresses.
Concept model of the Mars Express spacecraft
Enlarge
Concept model of the Mars Express spacecraft

Mars Express is a Mars exploration mission of the European Space Agency and the first planetary mission attempted by the agency. "Express" originally referred to the spacecraft's relatively short interplanetary voyage, a result of being launched when the orbits of Earth and Mars brought them closer than ever before in recorded history (about 60,000 years). However "express" also describes the speed and efficiency with which the spacecraft was designed and built.

Mars Express consists of two parts, the Mars Express Orbiter and the Beagle 2, a lander designed to perform exobiology and geochemistry research. It was hoped the lander would shed light on whether Mars had once supported or possibly currently supports living organisms. Many of the instruments on the orbiter, including the camera systems and some spectrometers, are duplicates of those lost in the failed launch of the Russian Mars 96 mission in 1996 (European countries had provided much of the instrumentation and financing for that unsuccessful mission). The basic design of Mars Express is based on ESA's Rosetta mission, on which considerable money was spent developing the spacecraft. The same design will also be used for the Venus Express mission in order to increase reliability and reduce development cost and time.

Contents

[edit] Timeline

The spacecraft was launched on June 2, 2003 from Baikonur Cosmodrome in Kazakhstan, using a Soyuz-Fregat rocket, and began its inter-planetary voyage. The orbiter entered Mars orbit on December 25, 2003, and Beagle 2 entered Mars' atmosphere the same day. After repeated attempts to contact the lander failed, it was declared lost on February 6, 2004, by the Beagle 2 Management Board. On February 11, ESA announced an inquiry would be held into the failure of Beagle 2.

In the meantime, the Mars Express Orbiter has started its science phase and is performing excellently at the start of a two year survey of Mars.

In 2005, ESA scientists reported that the OMEGA (Visible and Infrared Mineralogical Mapping Spectrometer)(Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) instrument data indicates the presence of hydrated sulphates, silicates and various rock-forming minerals.

The Fourier spectrometer has detected methane in the atmosphere coming from areas near the equator with subsurface ice, a very important discovery indicating either some form of active vulcanism or subsurface microorganisms.[1]

On May 4, 2005, Mars Express deployed the first of its two 20-metre-long radar booms for its MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) experiment. At first the boom didn't lock fully into place; however, exposing it to sunlight for a few minutes on May 10 fixed the glitch. The second 20 m boom was successfully deployed on June 14. Both 20 m booms were needed to create a 40 m dipole antenna for MARSIS to work; a less crucial 7-meter-long monopole antenna was deployed on June 17. The radar booms were originally scheduled to be deployed in April 2004, but this was delayed out of fear that the deployment could damage the spacecraft through a whiplash effect. Due to the delay it was decided to split the four week commissioning phase in two parts, with two weeks running up to July 4 and another two weeks in December 2005. Nominal science observations began during July 2005. (For more info, see [1], [2], and ESA press release.)

In November 2005, with just a few weeks of measurements having been taken thus far, ESA released data from MARSIS which included buried impact craters, and hints of the presence of underground water-ice.

[edit] Mars Express instruments

  • Visible and Infrared Mineralogical Mapping Spectrometer (OMEGA)(Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) - France - Determines mineral composition of the surface up to 100 m resolution
  • Ultraviolet and Infrared Atmospheric Spectrometer (SPICAM) - France - Assesses elemental composition of the atmosphere
  • Sub-Surface Sounding Radar Altimeter (MARSIS) - Italy - A radar altimeter used to assess composition of sub-surface aimed at search for frozen water.
  • Planetary Fourier Spectrometer (PFS) - Italy - Makes observations of atmospheric temperature and pressure (observations suspended in September 2005: [3], currently working)
  • Energetic Neutral Atoms Analyser (ASPERA) - Sweden - Investigates interactions between upper atmosphere and solar wind
  • High Resolution Stereo Camera (HRSC)- Germany - Produces color images with up to 2 m resolution
  • Mars Express Lander Communications (MELACOM) - UK - Allows Mars Express to act as a communication relay for landers on the Martian surface.
  • Mars Radio Science Experiment (Mars) - Uses radio signals to investiage atmosphere, surface, and subsurface

[edit] See also

[edit] External links

[edit] References

  1. ^ Formisano V, Atreya S, Encrenaz T, Ignatiev N, Giuranna M (2004). "Detection of methane in the atmosphere of Mars". Science 306: 1758-1761.