June 23, 2000
The evidence is in the form of images taken with the camera on board NASA's Mars Global Surveyor (MGS), the only spacecraft now in orbit around the red planet. The images show surprisingly young features, most probably created by the seepage of groundwater on crater and valley slopes. Most of the features are at high latitudes in the southern hemisphere. They suggest that liquid water may still exist much closer to the surface of Mars than anyone thought possible, given the thin atmosphere and low temperatures on the planet today.
The evidence raises the stakes over two questions that Mars Express will set out to answer. Where is the water that flowed so copiously on the red planet early in its history? And is there life on Mars?
It now seems likely that much of the water remains in underground aquifers and may even be seeping to the surface in a few places today. If so, what allows the water to remain liquid on the surface long enough to carve the features seen by MGS? Are we witnessing evidence of the type of internal heating that gives rise to hot springs on Earth? Or are conditions at the surface sometimes different from what we expect?
"The water must be at less than 1 km depth and possibly as little as 100 m. This means that the radar (MARSIS) on board Mars Express should be able to detect it quite easily," says Jean-Loup Bertaux Principal Investigator for Mars Express's SPICAM experiment. The 1 km depth is well within the radar's capability of mapping underground water to a depth of 5 km.
"The discovery opens up again the door to life on Mars and adds impetus to Beagle 2, Mars Express's lander whose job is to look for signs of present and extinct life," says Chicarro. "On Earth, we know of all the incredible variety of organisms that survive in underground water, especially around hot springs. It could now be that this sort of environment exists on Mars."
Several Mars Express instruments will also be re-examining their list of interesting sites for special observation. "We'll be thinking about the most efficient way to operate our instrument to analyse as many of these water features as possible," says Gerhard Neukum, Principal Investigator for the High Resolution Stereo Camera (HRSC) on Mars Express. "The HRSC will be able to get images with as high a resolution as the camera on MGS, but we'll be able to point the camera more accurately and will be able to investigate the topography and morphology in great detail."
"Until these latest MGS images, my working hypothesis had been that Mars has come to rest, but it now seems that there's more activity than we'd expected," says Neukum.
Image 2
Numerous examples of Martian gullies that start in a layer roughly a
hundred metres below the surface (credit: NASA Mars Global Surveyor)
January 26, 2000
More at:
http://sci.esa.int/newsitem.cfm?TypeID=1&ContentID=9011&Storytype=22
13 Jan 2000
The meeting brought to an end the process known as the Preliminary Design Review (PDR), which scrutinises all stages of the design phase (Phase B). "The meeting went smoothly and the outcome is that Mars Express moves now full steam into Phase C/D (the construction phase)," said Rudi Schmidt, Mars Express Project Manager. "The findings of the review team will be taken on board by the Mars Express project and resolved as part of the normal work. This is a very good result and we have been popping a few corks."
An illustration supporting this release is available.
8 Dec 1999
Mars Polar Lander was due to land near the red planet's south pole last Friday. The spacecraft appeared to be on target and functioning well until entry into the Martian atmosphere when radio contact was lost, as expected, during the descent. Contact, however, was not re-established after touchdown and all attempts to establish it since have failed. NASA will continue attempts for another two weeks, but as time passes, the chances diminish of finding the lander and its two probes intact.
Mars Polar Lander was built in line with NASA's "faster, cheaper, better" philosophy which aims to cut the cost of, and increase opportunities for, space exploration. Mars Express, due for launch in June 2003, is also being built more quickly and cheaply than any of ESA's previous comparable planetary missions. "If one does a mission cheap and fast then risk goes up," says Schmidt. "But we are taking steps to reduce it by choosing the simplest possible design, performing a lot of system level testing, using existing designs and hardware, maintaining a conventional quality assurance programme and reducing flexibility and services to the scientific payload."
Mars Polar Lander, like Mars Express, is part of an international effort to explore Mars during the first decade of next century. "Its loss may cause a dip in confidence among the many international partners involved in exploration of the red planet. But we must learn from the recent failures and work even harder to safeguard the future missions," says Marcello Coradini, solar system manager at ESA and former chairman of the International Mars Exploration Working Group.
11 Nov 1999
Another important element of the payload was also confirmed. Following the positive outcome of various reviews, both at UK and European level, the UK Mars lander Beagle-2 was considered sufficently mature, both technically and financially, to commence Phase C/D in January 2000. The confirmation by SPC, as requested by the UK SPC delegation, comes in advance of the previously planned date (February 2000). As a consequence, the development of the entire Mars Express payload, Orbiter and Lander, can proceed in full harmony.
An image supporting this article is available.
11 Jun 1999
The Agency's Science Programme Committee (SPC) approved Mars Express after ESA's Council, meeting at ministerial level in Brussels on 11 and 12 May, had agreed the level of the science budget for the next 4 years, just enough to make the mission affordable. "Mars Express is a mission of opportunity and we felt we just had to jump in and do it. We are convinced it will produce first-rate science", says Hans Balsiger, SPC chairman.
As well as being a first for Europe in Mars exploration, Mars Express will pioneer new, cheaper ways of doing space science missions. "With a total cost of just 150 million euros, Mars Express will be the cheapest Mars mission ever undertaken", says Roger Bonnet, ESA's Director of Science.
Mars Express will be launched in June 2003. When it arrives at the red planet six months later, it will begin to search for water and life. Seven instruments, provided by space research institutes throughout Europe, will make observations from the main spacecraft as it orbits the planet. Just before the spacecraft arrives, it will release a small lander, provided by research institutes in the UK, that will journey on to the surface to look for signs of life.
The lander is called Beagle 2 after the ship in which Charles Darwin sailed round the world in search of evidence supporting his theory of evolution. But just as Darwin had to raise the money for his trip, so the search is on for public and private finance for Beagle 2. "Beagle 2 is an extremely important element of the mission", says Bonnet.
Europe's space scientists have envisaged a mission to Mars for over fifteen years. But limited funding has prevented previous proposals from going ahead. The positioning of the planets in 2003, however, offers a particularly favourable passage to the red planet -- an opportunity not to be missed. Mars Express will be joined by an international flotilla of spacecraft that will also be using this opportunity to work together on scientific questions and pave the way for future exploration.
ESA is now able to afford Mars Express because it will be built more quickly and cheaply than any other comparable mission. It will be the first of the Agency's new flexible missions, based on maximum reuse of technology off-the-shelf and from other missions (the Rosetta cometary mission in this case). Mars Express will explore the extent to which innovative working practices, now made possible by the maturity of Europe's space industry, can cut mission costs and the time from concept to launch: a new kind of relationship with industrial partners is starting. "We are adopting a new approach to management by delegating to Matra Marconi Space (the prime contractor) responsibility for the whole project. This means we can reduce the ESA's management costs" says Bonnet.
Despite the knock-down price, however, the future of Mars Express has hung in the balance because of the steady erosion of ESA's space science budget since 1995. Last November, the SPC said the mission could go ahead only if it could be afforded without affecting missions already approved, especially the FIRST infra-red observatory and the Planck mission to measure the cosmic microwave background.
On 19/20 May, the SPC, which has the ultimate decision over the Agency's science missions, agreed that the level of resources allowed was just sufficient to allow Mars Express to go ahead. "To do such an ambitious mission for so little money is a challenge and we have decided to meet", says Balsiger.
USEFUL LINKS FOR THIS STORY
From Mars Society Special Bulletin #15
April 22, 1999
Beagle 2, the first European spacecraft designed to land on another world, is Britain's contribution to the planned European Mars Express mission.
In March, the first practical field tests of Beagle 2 components took place when a prototype "mole" rover was put through its paces at a disused quarry in southern England. The mole -- a one-foot, long self-propelled vehicle -- can be deployed via a mobile launch system operated by a remote manipulator arm aboard the Beagle 2 lander. The aptly named mole is designed to burrow under Martian rocks to retrieve soil samples that have lain hidden from the worst effects of the Sun's u/v radiation. Samples can then be returned to the lander for analysis by on-board systems.
Tests of further elements of the Beagle 2 package can be expected later this year, and the Mars Society's U.K. web site will be carrying pictures of the mole in action, as soon as they are available.
Information on the Beagle 2 lander can be found at:
http://www.marssociety.org.uk/beagle2.htm
From: Ron Baalke
April 21, 1999
As demonstrated by NASA's Pathfinder mission and the highly celebrated Sojourner rover, robotics and rovers are essential elements of missions to explore planets and comets, to deploy instruments around a lander spacecraft, to provide visual observation, to sample surface material, and to feed analysis instruments. Such robotics have to function properly and be versatile in poorly known and often difficult terrain, with very restricted means of intervention from Earth due to the extreme remoteness.
The European approach to planetary rovers is to build smaller rovers, so-called "micro-rovers" or even "nano-rovers". The rover having obtained the highest rating by ESA in a recent comparison of five different designs, is the "Nanokhod" rover, which is a rugged, simple, reliable yet effective rover, to deploy instruments in the surroundings of a lander. It is equipped with a tether cable, providing the rover with power and data connection to the lander. The rover is able to carry four scientific instruments to analyse different aspects of the soil and rocks on Mars, whereas Sojourner carried only one instrument.
Depending on the constellation of the planets, it takes between 10 and 40 minutes for radio signals to travel back and forth between Earth and Mars. This makes it impossible to control a Mars rover like driving a radio-controlled toy car here on Earth. Instead, high-level commands, stating the destinations the rover should go to and the preferred path, are generated on Earth and sent to the lander on the Martian surface. The lander control system on Mars afterwards controls the details of the rover's actual path to avoid obstacles in order to safely reach the destinations without tipping over or getting stuck.
The prime contractor is Space Applications Services (SAS) in Zaventem, who will design the complete system for the control of the Nanokhod rover, and implement the ground control station to define and programme the high-level commands, and to visualize a simulated rover moving in real-time in a model of the terrain around the lander obtained from images transmitted from stereo-cameras on the lander.
SAS is in this project supported by the Katholieke Universiteit Leuven (KUL) for terrain modelling / visualisation and path planning and by OptiDrive in Heverlee for the mechanical structure on which the stereo cameras are mounted; by the German Aerospace Centre (DLR) for lander software and space-qualified cameras; and the company von Hoerner & Sulger who builds the Nanokhod rover.
An agreement was signed in January between SAS and an organisation called C-CORE in Canada to use the SAS robot control system for controlling robots and vehicles that are extensively used in mining operations, which represents an important industry in the Canadian economy. The use of the SAS robot control systems will allow drivers of underground vehicles to get out from the harsh environment of the mine tunnels and instead operate the vehicles and mining machinery from control stations on the surface. This is a typical example of how technology developed for space can be used for applications here on Earth. SAS is currently identifying further terrestrial applications of this robot control system.
Space Applications Services - SAS - is a leader in the field of space systems design and software engineering, and implements leading edge technology and information systems for command, control, and training. SAS provides advanced information systems for both space and industrial applications in the areas of Spacecraft and ground segment design and operations, Automated planning and scheduling, Robotic control systems, Training and performance support, Internet and multi-media applications.
Southwest Research Institute (SwRI)
San Antonio, Texas
SwRI engineers will build part of the analyzer of space plasmas and energetic atoms (ASPERA-3) instrument -- one of a suite of instruments aboard Mars Express that will examine the present and past states of the martian atmosphere. Whether water on the planet might have sometime sustained life will also be addressed.
"The fact that Earth can maintain life is a unique condition in the solar system," says Dr. David Winningham, ASPERA-3 co-investigator and an Institute scientist in the SwRI Instrumentation and Space Research Division. "Mars Express could tell researchers what variables are needed to first create, then preserve over geological time, oceans and atmospheres."
Magnetic and gravity fields help maintain an atmosphere on Earth. When the solar wind, the supersonic stream of charged particles flowing out from the Sun, interacts with the planet, ion and electron particles become ionized and remain trapped in the magnetic field, enabling Earth to sustain an active, living atmosphere. The Earth's magnetic field acts as an invisible force that reflects away some of the harmful components, such as cosmic rays, brought by the solar wind.
On Mars, interactions with the solar wind also ionize particles, but they fly away because the planet lacks a magnetic field and a strong gravitational field. Over time, the release of particles continuously erodes the martian atmosphere. By examining the ionic composition with the Mars Express instruments, researchers will be able to determine whether particles, especially water particles, continue to fly away. After combining the data with theory, researchers can estimate the length of time atmospheric changes have been occurring. The spacecraft will also help researchers determine which component, if any, was missing from the martian atmosphere that allowed the planet to eventually become geologically inactive.
The ASPERA-3 instrument will measure the ion and electron particles of the planet's atmosphere. An additional neutral atom imager will return a volumetric image of the martian atmosphere to help characterize its present state -- how particles are flying away in a volumetric sense, for example -- and how the atmosphere has evolved. Data will also help determine if the changes contributed to the dehydration of Mars and the loss of its oceans and atmosphere, says Winningham.
SwRI has provided a family of imaging instruments, with different adaptations for varying conditions, for a number of NASA and ESA missions. The plasma experiment for planetary exploration (PEPE) instrument was launched aboard Deep Space One in October 1998, and the Cassini plasma spectrometer (CAPS) was launched aboard Cassini in October 1997. Similar instruments will also fly aboard the ESA missions Astrid 2 on December 10, MUNIN in late 1999, and Rosetta in 2003.
For more information about Mars Express and the ASPERA-3 instrument, visit the NASA web page at:
http://quest.arc.nasa.gov/mars/background/express.html.
ESA
Paris, 5 November 1998
"The green light for Mars Express shows that Europe is perfectly capable of seizing special chances in exploring space," said Roger Bonnet, ESA's director of science. "At a cost to ESA of 150 million ECU, Mars Express is the cheapest Mars mission ever, yet its importance and originality are far greater than the price tag suggests."
Bonnet continued: "Mars Express has been advertised by the Science Programme Committee as a test case for new approaches in procuring and managing future science projects, with a view to achieving major savings. In the international arena, Mars Express will confirm Europe's interest in a major target for space research in the new century, when we make our forceful debut at the Red Planet. In fact, Mars Express is designed to be a pivotal element of an international multi-mission, global effort for the exploration of Mars."
Development of the spacecraft will now proceed swiftly, to meet the deadline of an exceptionally favourable launch window early in June 2003. Mars Express will go into orbit around Mars at Christmas 2003.
Seven scientific instruments on board will include a high-resolution camera, a range of spectrometers, and a radar to penetrate below the surface. For the first time in the history of the exploration of the Red Planet, scientists can hope to detect sub-surface water, whether it exists in the form of undergound rivers, pools, glaciers or permafrost.
Signs of life on Mars, whether extinct or continuing today, may reveal themselves to a lander carried by Mars Express. This is Beagle 2, a project led by the Open University in the United Kingdom, with contributions from many other European countries. The lander also promises invaluable information about the chemistry of the Martian surface and atmosphere. Beagle 2 is to be independently funded. Some of the necessary funds have already been raised and ESA has agreed with the principal investigator to keep a place for Beagle 2 aboard Mars Express. The financial situation will be verified at a date to be agreed with the mission's prime contractor.
For more details about the mission visit the Mars Express web site
ESA
Paris, 19 June 1998
Why the hurry? The deadline is set in the form of a favourable launch opportunity just five years from now. The positions of Earth and Mars in their orbits at that time will mean that a spacecraft can reach Mars more quickly, carrying a greater weight of instruments, than from any other launch date in the next decade. A decision to proceed taken towards the end of 1998 would leave less than five years to create, test and launch a complex spacecraft and meet that deadline. Most judgements about Mars Express and its instruments have therefore to be made in advance if the engineers and scientists are to make sure that everything is ready for lift-off in June 2003.
The brisk pace is also fitting for the prototype of a new class of Flexi (flexible) missions. Mars Express is the first of what should become a series of relatively inexpensive and quick projects introduced into ESA's space science, to seize special opportunities to broaden the programme. At about one-quarter of the cost of the major Cornerstone missions, which have long lead-times, the Flexi missions replace the previous class of Medium missions, in ESA's forward planning. Streamlined management procedures for the Flexi missions help to keep down the costs to ESA while placing more responsibility on the industrial contractors and the participating scientists.
Space scientists advising ESA recognized the special opportunity for Mars Express after the failure of the Russian Mars 96 mission, in November 1996. It left a gap in the international programme for the exploration of Mars, and some of the key instruments which fell into the Pacific Ocean with Mars 96 had been devised by space scientists in ESA member states. The strong scientific interest in Mars within Europe, and the predicted advantage of the mid-2003 launch, led to the proposal to add Mars Express to ESA's programme.
A team led by the University of Rome will contribute the Subsurface Sounding Radar/Altimeter on Mars Express. This instrument will map the distribution of ice and liquid water with radar pulses penetrating the martian surface. It will chart the topography of the surface too, and the observed effects of the martian ionosphere on the radar waves will show how the solar wind influences the state of the atmosphere.
The link between the solar wind and the fate of water on Mars is the concern of the Swedish Institute of Space Physics in Kiruna, and the ASPERA experiment lead. Mars may have lost most of its water by solar effects destroying water vapour in the atmosphere. By sensing neutral and charged atomic particles in the planet's vicinity, ASPERA will shed light on any such mechanism for dehydrating Mars.
The escape of gas from Mars will also be seen by SPICAM UV, which is the special responsibility of the Service d'Aeronomie at Verrieres near Paris. The instrument will examine the martian atmosphere by ultraviolet light. A major aim of SPICAM UV is to clarify the threat that solar ultraviolet rays and oxidizing chemicals (ozone and hydroxyl) may have posed to any life incipient on Mars.
Comprehensive observations of the martian atmosphere, and of its gases, dust and weather, will come from PFS, an infrared instrument provided by a team led by the Istituto di Fisica dello Spazio Interplanetario in Frascati. It measures the intensities of infrared rays at sharply defined wavelengths. PFS will also monitor temperature changes on the surface, and investigate the seasonal frost on Mars.
To provide minerological information about the surface of Mars is the job of the mapping spectrometer OMEGA, supervised by the Institut d'Astrophysique Spatiale at Orsay near Paris. It will observe the gases and dust in the atmosphere too, but the main aim of OMEGA is to use visible and infrared signatures to distinguish materials on the surface -- silicates, hydrated minerals, oxides and carbonates, organic frosts and ices.
Confirming Europe's chance to make a distinctive and original contribution to the study of Mars is a unique German instrument, the High Resolution Stereo Camera. It will provide unprecedented images in stereo and colour, showing details of the surface down to 12-15 metres, across huge areas. Its images will enable scientists to re-evaluate the the history of Mars and its volcanic and water-eroded features, as well as giving clearer impressions of dust storms, frost and other weather-related events. The principal investigator for the stereo camera is at the Institut fur Planetenerkundung in Berlin.
A valuable addition to the science of Mars Express requires no special onboard equipment. The Radio Science Experiment, masterminded at the University of Cologne, will use the radio communications link between the spacecraft and the Earth to probe the martian atmosphere. Effects of the martian surface on radio signals reflected from it will give fresh clues to the surface composition, and the radio science observations will help to refine the measurements of heights and effects of gravity, made with the stereo camera.
Family resemblances between the experiments on Mars Express and those selected for the Rosetta mission to Comet Wirtanen show a coherence in ESA's approach to the science of the Solar System. Rosetta is due to fly a few months before Mars Express.
For more details visit the Mars Express web site.
JOINT PRESS NOTICE FROM THE OPEN UNIVERSITY and ROYAL ASTRONOMICAL SOCIETY
25 February 1998
In the last few days, the European Space Agency (ESA) has received scientific and technical proposals from investigators across Europe wishing to be involved in Mars Express. The mission is planned to launch in 2003, a date which offers the best opportunity (in terms of the relative positions of Mars and Earth) to study the red planet at the beginning of the next millennium.
Amongst the proposals received by ESA are several for orbiter science which were originally planned for the ill-fated Mars 96 mission - for example, studying atmospheric composition or mapping the surface at various wavelengths. New concepts include a ground-penetrating radar which will be able to search for the planet's missing water. In addition to the orbiter payload, a group of three landers will touch down on the surface of Mars and offer an exciting extension to the scientific investigations. Two small (45 kg) landers have been proposed to investigate geophysical properties, including seismology and meteorology. A larger (90 kg) lander, known as Beagle 2, will also be part of the network of geophysical stations, although its main task will be to answer geochemical questions, particularly whether life could have once existed on Mars. Beagle 2 is named after the 19th century ship whose voyage enabled Charles Darwin to make momentous progress in understanding the evolution of life on Earth. The Beagle 2 consortium is headed by Professor Colin Pillinger of the Planetary Sciences Research Institute (PSRI) at the Open University. Dr. Mark Sims of the Space Sciences Centre at the University of Leicester is the Project Manager.
Beagle 2 offers a unique opportunity for British and European university and government scientists and industrial partners to work together to explore Mars. Its integrated package of instruments will analyse samples collected from below the inhospitable surface in search of a much fuller understanding of the planet's geochemistry and of evidence for past life. The Beagle 2 instrument providers are supported by a large number of researchers in the life sciences who expect to benefit mutually from comparisons between Earth and Mars.