Europe Explores The Planets

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Europe Explores The Planets

Individual results from Mars Express and Venus Express can be found in the following threads:

• Mars Express
  
• Exploration of Venus

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The planetary adventure continues - Mars Express and Venus Express operations extended

Venus Express is making unprecedented studies of the largely unkown phenomena taking
place in the Venusian atmosphere. Its suit of instruments is also digging into the interaction
between the solar wind and the planetary environment. Finally, the mission is also gathering
glimpses about the planet's surface, striclty coupled with the dense atmosphere.

Credits: ESA - AOES Medialab

27 February 2007
ESA's Mars Express and Venus Express missions, to explore our nearest neighbour planets Mars and Venus respectively, will continue to operate until early-May 2009. The decision was unanimously taken by ESA's Science Programme Committee last Friday.

The Science Programme Committee recognised the outstanding legacy that Mars Express and Venus Express are building for future generations of scientists, and noted the invaluable heritage that these missions are leaving to future missions to these planets. The decision to extend the two missions will allow to continue the exploitation of their unique potential.

So far, both missions have allowed an amazing amount of scientific discoveries of the highest quality. Both spacecraft are equipped with a suite of sophisticated scientific instruments - many of which share a common design and the same scientific teams, and the prime objective of both the missions is a comprehensive study of the respective planets at outstanding spatial and spectral resolution.


Mars Express left Earth for Mars on 2 June 2003. It reached destination after a 6-month
journey, and it is making a thorough investigation of the planet since early 2004.

Credits: ESA - D. Ducros

The extension of the Mars Express and Venus Express operations will not only allow to complete the coverage carried out during the scientific phases that took place so far, but will also sustain the synergy that is being created in the interpretation of the data sets collected from both missions. Furthermore, their operational synergies have allowed for substantial cost reductions not possible when operating just one of these missions.

The scientists involved can now not only focus on planet-specific results, but focus on comparative planetology to provide new solid arguments for the current theories of planetary formation and evolution, for the conditions favourable for life to emerge in the Solar System, and for the interaction of terrestrial planets’ environment with the solar wind.

Mars Express – the present and the future


In this HRSC 3D perspective view of the Marwth Vallis area (shades of grey), OMEGA
has mapped the water-rich minerals (blue). No hydrated minerals or sediments have been
detected, either in the channel or in its opening. However, the outflow was so violent as to
erode and expose ancient hydrated clay-rich minerals, tracing an early era when water
was present.

Credits: ESA/OMEGA/HRSC

Mars Express’s watch-word is 'global mapping', at unprecedented resolution, of surface, subsurface and atmosphere of Mars, with particular emphasis on the search for water in its various states and on the search for signs of biological processes.

Results achieved by Mars Express so far include the evidence of volcanic, fluvial and glacial activity on Mars from very early in its history until very recently – possibly still going on today; the first ever sub-surface radar sounding of another planet, that led to the discovery of underground water-ice and of buried impact basins; the first comprehensive study of the mineralogical composition of the planets surface, which provided the first mineralogical evidence for the past history of water on Mars – now known with certainty to have been very abundant in the early epochs; the detection of methane in the atmosphere as a possible 'tracer' of present life on Mars or as an indicator of present volcanism; the first global measurements of the ozone levels on day- and night-sides; the existence of mid-latitude auroras on Mars; the first detailed and quantitative indications of the atmospheric escape processes - just to mention a few.


The HRSC obtained this image of Aureum Chaos during orbit 456 with a resolution of
approximately 25 metres per pixel. The scene shows an area located at about 3º South
and 335º East, looking roughly north to north-east.

In right-hand corner, a roughly five kilometre-wide region of bright material is observed.
This material appears to form distinct layers that may have been created by the evaporation
of fluids or by hydrothermal activity.

Credits: ESA/DLR/FU Berlin (G. Neukum)

For Mars Express, a major remaining goal to be achieved is the completion of global coverage in general terms. The mission’s unique capability to produce high-resolution, stereo images in colour for geological interpretation, its capability to study the surface roughness and mineralogy, and the capability to probe at unique depths the subsurface of areas of interest as far as water and ice are concerned, makes Mars Express the ideal 'tool' to select candidate landing sites for future missions, especially valuable when the maximum possible coverage will have been reached thanks to the extended mission. Because Mars Express instruments are also largely complementary to the instruments of other missions to Mars, the data set obtained by this mission becomes even more important.

Venus Express – looking further


This movie, built with infrared images taken by the Ultraviolet/Visible/Near-Infrared
spectrometer (VIRTIS) on board ESA’s Venus Express, provides a close-up view of the
double-eyed vortex at Venus south pole. The images (ranging from 4.5 to 5.1 microns)
were taken on 29 May 2006, from a distance of about 64 000 kilometres from the planet.

Thanks to the use of different wavelengths, VIRTIS probed the atmosphere at different
depths, ranging from 70 kilometres to about 60 kilometres altitude. It is interesting to
see how the images contrast and the details increase while approaching the 60
kilometres altitude.

Credits: ESA/VIRTIS/INAF-IASF/Obs. de Paris-LESIA

Venus Express is still only half-way through its (initially planned) nominal mission, but has already revealed features never detected in such detail before. These include the huge, 'double-eyed' atmospheric vortex at Venus South Pole and its 3D structure varying with the altitude, the first solid indications of the complex structures and sub-structures that characterise the thick and noxious atmosphere of the planet and its complex cloud and wind systems. These are also being studied at low altitudes, down to the surface, thanks to the first systematic exploitation ever of the so-called 'infrared windows' present in the atmosphere.

Venus Express’ results also include preliminary important measurements of the atmospheric chemistry and temperature, and the analysis of the atmospheric escape processes in combination with the action of the solar wind, fundamental to understand the water history and the evolution of the planet's atmosphere.


This visible/ultraviolet image of Venus (380 nanometres) was taken by the Ultraviolet/
Visible/Near-Infrared spectrometer (VIRTIS) on board ESA’s Venus Express spacecraft on
19 April 2006, during the first orbit (capture orbit) around the planet, from a distance of
about 190 000 kilometres.

In the day side (blue part) it is possible to see interesting atmospheric stripe-like structures.
Spotted for the first time by Mariner 10 in the 1970s, they may be due to the presence of
dust and aerosols in the atmosphere, but their true nature is still unexplained.

Credits: ESA/VIRTIS/INAF-IASF/Obs. de Paris-LESIA

Venus Express' extension will allow to achieve a global coverage of the atmosphere of this planet, so similar and at the same time so different from Earth. It will also allow to completely address, thanks to a thorough analysis of surface temperature and chemistry maps, the question on whether Venus is a planet still geologically and volcanically active.

Thanks to its extension Venus Express will also be able to continue the first extensive study of the strong green-house effect on the planet – a subject extremely interesting for planetary climate experts, and an important element of comparison for the evolution of the green-house effect on Earth.


Note

Mars Express was launched on 2 June 2003 and reached Mars 6 months later. It started its scientific observations in early 2004. The mission was already extended until end-October 2007, and will now operate for almost two more Earth-years.

Venus Express was launched on 9 November 2005 and arrived to its destination after a five-month journey. It started its scientific phase in early June 2006. Initially planned to operate until end-September 2007, the mission will now take advantage of the extension of its operations for almost two further Earth-years.

Source: ESA - News Edited April 11, 2007 by Waspie_Dwarf

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Shared satellite architecture enables more efficient mission control

11 April 2007

Credits: ESA/J. Mai - www.juergenmai.comb

Flight Control Teams for Mars Express and Venus Express now work side-by-side for key aspects of their routine activities. The close cooperation supports team spirit, cross-training and improved efficiency.

Thanks to a common spacecraft architecture and use of standardised mission control software, spacecraft controllers from the Mars Express and Venus Express Flight Control Teams (FCTs) are now able to work in tandem, each providing support to both missions and boosting team cooperation.

The sharing enables reduced costs and better efficiency while maintaining reliability and boosting teamwork.

Since the end of 2006, the Mars and Venus Express Dedicated Control Rooms (DCRs) have been shifted and collocated into a six-workstation 'Combined DCR' facility at ESOC; spacecraft controllers ('spacons') from each team now pull shared shifts. A spacon from either team can operate both their own and the other mission, uploading commands and monitoring routine spacecraft operations for both.

Combined shifts enable closer cooperation

ESOC's new Combined DCR

Credits: ESA/J. Mai - www.juergenmai.comb

One of the challenges to be solved was combining and blending the widely differing spacon shifts, which were previously customised to match the orbits - and hence ground tracking station passes - of each mission.

Venus Express is in a highly elliptical, once-per-24-hour orbit around Venus, while Mars Express is in a highly elliptical orbit that circles the Red Planet every 8 hours.

This artist's impression shows ESA's Mars Express, flying in a survival-mode configuration (nicknamed 'Sumo'), while it enters eclipse around Mars. The spacecraft is shown in the power-saving warm-up attitude, with its base pointed towards the Sun to maximise solar heating.

Credits: ESA, Celestiab

"Venus Express is pretty regular, while Mars Express has some ground station passes lasting eight hours and some lasting ten minutes. We finally devised an eight-hour-shift schedule based on Venus Express," said Peter Wright, a spacecraft analyst for Mars Express.

He adds that, "The biggest advantages have come in closer cooperation between the teams - there is better knowledge sharing and communications, as well as a bigger pool of cross-trained spacons."


Shared mission architecture in space and on the ground

In addition, the spacecraft platforms of Mars Express and Venus Express - the underlying physical frame of the spacecraft supporting common functions such as power, communications, avionics systems and flight control - share a common engineering heritage and were designed and built using many of the same systems and components (as was Rosetta).

Extensive cross-training boosts flexibility

Old Venus Express DCR is now used for testing, simulations.

Credits: ESA/J. Mai - www.juergenmai.com

Traditionally, each ESA mission has a dedicated Flight Control Team (FCT) assigned to control all aspects of a single spacecraft's operations. Each spacecraft was custom-designed for its scientific tasks and planned trajectory, so the mission control system on the ground was also custom-developed and FCT members were custom-trained and worked solely on their mission.

In this case, spacons, spacecraft analysts and some engineers from both missions have gone through cross-familiarisation on each other's mission, made easier by the commonalities between the two spacecraft and their mission control infrastructure.

Such training is not trivial; there can be up to 20 000 parameters that affect the operation of a spacecraft like Mars or Venus Express.

This commonality enabled ESA to launch the three missions to widely differing destinations on a budget which would otherwise have been much higher. The satellites' scientific instruments are, of course, customised to their intended targets, which vary widely, but even some of these are common as well.

In addition, all three missions use the SCOS-2000 (Spacecraft Operating System 2000) mission control software for ground control; this software was developed at ESOC and has become the European standard system.


Boosting tech-family teamwork and reducing costs

The project has further entailed a great deal of harmonisation work with respect to staff scheduling as well as scheduling of control activities and ground station communication slots. Overall, it is estimated that the project has saved the equivalent of one spacon position as well as bringing strong benefits in terms of resource sharing and efficiency.

"There have been no real problems, and now there's more interesting work to do for both teams of spacons. Sitting in the same control room helps a lot; the spacons also have better morale now with two complex missions to work on," said Norbert Schmitt, a long-time ESA spacecraft engineer from the Venus Express team

Source: ESA - News