HOME

TheInfoList



OR:

''Mars Express'' is a
space exploration Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is carried out mainly by astronomers with telescopes, its physical exploration though is conducted both by uncrewed robo ...
mission being conducted by the
European Space Agency , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (120 ...
(ESA). The ''Mars Express'' mission is exploring the planet
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...
, and is the first planetary mission attempted by the agency. "Express" originally referred to the speed and efficiency with which the
spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, ...
was designed and built. However, "Express" also describes the spacecraft's relatively short interplanetary voyage, a result of being launched when the orbits of Earth and Mars brought them closer than they had been in about 60,000 years. ''Mars Express'' consists of two parts, the ''Mars Express Orbiter'' and ''
Beagle 2 The ''Beagle 2'' is an inoperative British Mars lander that was transported by the European Space Agency's 2003 ''Mars Express'' mission. It was intended to conduct an astrobiology mission that would have looked for evidence of past life on Mar ...
'', a
lander Lander may refer to: Media and entertainment * ''Lander'' (computer game), computer game published by Psygnosis in 1999 * ''Lander'' (game demo), the 3D game demo provided with the Acorn Archimedes computer * Lander (Transformers), a fiction ...
designed to perform exobiology and geochemistry research. Although the lander failed to fully deploy after it landed on the Martian surface, the orbiter has been successfully performing scientific measurements since early 2004, namely, high-resolution imaging and mineralogical mapping of the surface, radar sounding of the subsurface structure down to the permafrost, precise determination of the atmospheric circulation and composition, and study of the interaction of the
atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A ...
with the
interplanetary medium The interplanetary medium (IPM) or interplanetary space consists of the mass and energy which fills the Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding ...
. Due to the valuable science return and the highly flexible mission profile, ''Mars Express'' has been granted several mission extensions. The latest was approved on 1 October 2020 and runs until 31 December 2022. Some of the instruments on the orbiter, including the camera systems and some
spectrometers A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the ...
, reuse designs from 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 design of ''Mars Express'' is based on ESA's Rosetta mission, on which a considerable sum was spent on development. The same design was also used for ESA's ''
Venus Express ''Venus Express'' (VEX) was the first Venus exploration mission of the European Space Agency (ESA). Launched in November 2005, it arrived at Venus in April 2006 and began continuously sending back science data from its polar orbit around Venus. ...
'' mission in order to increase reliability and reduce development cost and time. Because of these redesigns and repurposings, the total cost of the project was about $345 million- less than half of comparable U.S. missions. Arriving at Mars in 2003, ago (and counting), it is the second longest surviving, continually active spacecraft in orbit around a planet other than Earth, behind only NASA's still active ''
2001 Mars Odyssey ''2001 Mars Odyssey'' is a robotic spacecraft orbiting the planet Mars. The project was developed by NASA, and contracted out to Lockheed Martin, with an expected cost for the entire mission of US$297 million. Its mission is to use ...
''.


Mission profile and timeline overview


Mission overview

The ''Mars Express'' mission is dedicated to the orbital (and originally in-situ) study of the interior, subsurface, surface and atmosphere, and environment of the planet Mars. The scientific objectives of the ''Mars Express'' mission represent an attempt to fulfill in part the lost scientific goals of the Russian Mars 96 mission, complemented by exobiology research with Beagle-2. Mars exploration is crucial for a better understanding of the Earth from the perspective of comparative planetology. The spacecraft originally carried seven scientific instruments, a small lander, a lander relay and a Visual Monitoring Camera, all designed to contribute to solving the mystery of Mars' missing water. All of the instruments take measurements of the surface, atmosphere and interplanetary media, from the main spacecraft in polar orbit, which will allow it to gradually cover the whole planet. The total initial ''Mars Express'' budget excluding the lander was
The euro sign () is the currency sign used for the euro, the official currency of the eurozone and unilaterally adopted by Kosovo and Montenegro. The design was presented to the public by the European Commission on 12 December 1996. It consists o ...
150 million. The prime contractor for the construction of ''Mars Express'' orbiter was EADS Astrium Satellites.


Mission preparation

In the years preceding the launch of a spacecraft numerous teams of experts distributed over the contributing companies and organisations prepared the space and ground segments. Each of these teams focussed on the area of its responsibility and interfacing as required. A major additional requirement raised for the Launch and Early Orbit Phase (LEOP) and all critical operational phases was that it was not enough merely to interface; the teams had to be integrated into one Mission Control Team. All the different experts had to work together in an operational environment and the interaction and interfaces between all elements of the system (software, hardware and human) had to run smoothly for this to happen: * the flight operations procedures had to be written and validated down to the smallest detail; * the
control system A control system manages, commands, directs, or regulates the behavior of other devices or systems using control loops. It can range from a single home heating controller using a thermostat controlling a domestic boiler to large industrial ...
had to be validated; * system Validation Tests (SVTs) with the satellite had to be performed to demonstrate the correct interfacing of the ground and space segments; * mission Readiness Test with the
Ground Stations A ground station, Earth station, or Earth terminal is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft (constituting part of the ground segment of the spacecraft system), or reception of radio waves fro ...
had to be performed; * a Simulations Campaign was run.


Launch

The spacecraft was launched on June 2, 2003, at 23:45 local time (17:45 UT, 1:45 p.m. EDT) from
Baikonur Cosmodrome ''Baiqoñyr ğaryş ailağy'' rus, Космодром Байконур''Kosmodrom Baykonur'' , image = Baikonur Cosmodrome Soyuz launch pad.jpg , caption = The Baikonur Cosmodrome's "Gagarin's Start" Soyuz ...
in
Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, using a Soyuz-FG/ Fregat rocket. The ''Mars Express'' and Fregat booster were initially put into a 200 km Earth parking orbit, then the Fregat was fired again at 19:14 UT to put the spacecraft into a Mars transfer orbit. The Fregat and ''Mars Express'' separated at approximately 19:17 UT. The
solar panel A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...
s were then deployed and a trajectory correction manoeuvre was performed on June 4 to aim ''Mars Express'' towards Mars and allow the Fregat booster to coast into interplanetary space. The ''Mars Express'' was the first Russian-launched probe to successfully make it out of low Earth orbit since the Soviet Union fell.


Near Earth commissioning phase

The Near Earth commissioning phase extended from the separation of the spacecraft from the launcher upper stage until the completion of the initial check out of the orbiter and payload. It included the solar array deployment, the initial attitude acquisition, the declamping of the Beagle-2 spin-up mechanism, the injection error correction manoeuvre and the first commissioning of the spacecraft and payload (final commissioning of payload took place after Mars Orbit Insertion). The payload was checked out one instrument at a time. This phase lasted about one month.


The interplanetary cruise phase

This five month phase lasted from the end of the Near Earth Commissioning phase until one month prior to the Mars capture manoeuvre and included trajectory correction manoeuvres and payloads calibration. The payload was mostly switched off during the cruise phase, with the exception of some intermediate check-outs. Although it was originally meant to be a "quiet cruise" phase, It soon became obvious that this "cruise" would be indeed very busy. There were star Tracker problems, a power wiring problem, extra manoeuvres, and on October 28, the spacecraft was hit by one of the largest
solar flare A solar flare is an intense localized eruption of electromagnetic radiation in the Sun's atmosphere. Flares occur in active regions and are often, but not always, accompanied by coronal mass ejections, solar particle events, and other sol ...
s ever recorded.


Lander jettison

The
Beagle 2 The ''Beagle 2'' is an inoperative British Mars lander that was transported by the European Space Agency's 2003 ''Mars Express'' mission. It was intended to conduct an astrobiology mission that would have looked for evidence of past life on Mar ...
lander was released on December 19, 2003, at 8:31 UTC (9:31 CET) on a ballistic cruise towards the surface. It entered Mars' atmosphere on the morning of December 25. Landing was expected to occur at about 02:45 UT on December 25 (9:45 p.m. EST December 24). However, after repeated attempts to contact the lander failed using the ''Mars Express'' craft and the
NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...
''
Mars Odyssey ''2001 Mars Odyssey'' is a robotic spacecraft orbiting the planet Mars. The project was developed by NASA, and contracted out to Lockheed Martin, with an expected cost for the entire mission of US$297 million. Its mission is to use spectro ...
'' orbiter, it was declared lost on February 6, 2004, by the Beagle 2 management board. An inquiry was held and its findings were published later that year.


Orbit insertion

''Mars Express'' arrived at Mars after a 400 million km journey and course corrections in September and in December 2003. On December 20 ''Mars Express'' fired a short thruster burst to put it into position to orbit the planet. The ''Mars Express'' orbiter then fired its main engine and went into a highly elliptical initial-capture orbit of 250 km × 150,000 km with an inclination of 25 degrees on December 25 at 03:00 UT (10:00 p.m., December 24 EST). First evaluation of the orbital insertion showed that the orbiter had reached its first milestone at Mars. The orbit was later adjusted by four more main engine firings to the desired 259 km × 11,560 km near-polar (86 degree inclination) orbit with a period of 7.5 hours. Near periapsis (nearest to Mars) the top deck is pointed down towards the Martian surface and near apoapsis (farthest from Mars in its orbit) the high gain antenna will be pointed towards Earth for uplink and downlink. After 100 days the apoapsis was lowered to 10,107 km and periapsis raised to 298 km to give an orbital period of 6.7 hours.


MARSIS deployment

On May 4, 2005, ''Mars Express'' deployed the first of its two 20-metre-long
radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...
booms for its MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) experiment. At first the boom did not 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 In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole wi ...
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. The deployment of the booms was a critical and highly complex task requiring effective inter-agency cooperation ESA, NASA, Industry and public Universities. Nominal science observations began during July 2005. (For more info see, an
ESA Portal - Mars Express radar ready to work
ESA press release.)


Operations of the spacecraft

Operations for ''Mars Express'' are carried out by a multinational team of engineers from ESA's Operation Centre ( ESOC) in
Darmstadt Darmstadt () is a city in the state of Hesse in Germany, located in the southern part of the Rhine-Main-Area (Frankfurt Metropolitan Region). Darmstadt has around 160,000 inhabitants, making it the fourth largest city in the state of Hesse ...
. The team began preparations for the mission about 3 to 4 years prior to the actual launch. This involved preparing the ground segment and the operational procedures for the whole mission. The Mission Control Team is composed of the Flight Control Team, Flight Dynamics Team, Ground Operations Managers, Software Support and Ground Facilities Engineers. All of these are located at ESOC but there are additionally external teams, such as the Project and Industry Support teams, who designed and built the spacecraft. The Flight Control Team currently consists of: * The Spacecraft Operations Manager * Six Operations Engineers (including three Mission Planners) * One Spacecraft Analyst * Six spacecraft controllers (SpaCons), shared with ExoMars Trace Gas Orbiter, BepiColombo and
Solar Orbiter The Solar Orbiter (SolO) is a Sun-observing satellite developed by the European Space Agency (ESA). SolO, designed to obtain detailed measurements of the inner heliosphere and the nascent solar wind, will also perform close observations of ...
. The team build-up, headed by the Spacecraft Operations Manager, started about 4 years before launch. He was required to recruit a suitable team of engineers that could handle the varying tasks involved in the mission. For ''Mars Express'' the engineers came from various other missions. Most of them had been involved with Earth orbiting satellites.


Routine phase: science return

Since orbit insertion ''Mars Express'' has been progressively fulfilling its original scientific goals. Nominally the spacecraft points to Mars while acquiring science and then slews to Earth-pointing to downlink the data, although some instruments like Marsis or Radio Science might be operated while spacecraft is Earth-pointing.


Orbiter and subsystems


Structure

The ''Mars Express'' orbiter is a cube-shaped spacecraft with two
solar panel A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...
wings extending from opposite sides. The launch mass of 1223 kg includes a main bus with 113 kg of payload, the 60 kg lander, and 457 kg of propellant. The main body is 1.5 m × 1.8 m × 1.4 m in size, with an aluminium honeycomb structure covered by an aluminium skin. The solar panels measure about 12 m tip-to-tip. Two 20 m long wire
dipole antenna In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole wi ...
s extend from opposite side faces perpendicular to the solar panels as part of the radar sounder.


Propulsion

The Soyuz/Fregat launcher provided most of the thrust ''Mars Express'' needed to reach Mars. The final stage of the Fregat was jettisoned once the probe was safely on a course for Mars. The spacecraft's on-board means of propulsion was used to slow the probe for Mars orbit insertion and subsequently for orbit corrections. The body is built around the main propulsion system, which consists of a bipropellant 400 N main engine. The two 267-liter propellant tanks have a total capacity of 595 kg. Approximately 370 kg are needed for the nominal mission. Pressurized helium from a 35-liter tank is used to force fuel into the engine. Trajectory corrections will be made using a set of eight 10 N thrusters, one attached to each corner of the spacecraft bus. The spacecraft configuration is optimized for a Soyuz/Fregat, and was fully compatible with a
Delta II Delta II was an expendable launch system, originally designed and built by McDonnell Douglas. Delta II was part of the Delta rocket family and entered service in 1989. Delta II vehicles included the Delta 6000, and the two later Delta 7000 va ...
launch vehicle.


Power

Spacecraft power is provided by the solar panels which contain 11.42 square meters of silicon cells. The originally planned power was to be 660 W at 1.5 AU but a faulty connection has reduced the amount of power available by 30%, to about 460W. This loss of power does significantly impact the science return of the mission. Power is stored in three
lithium-ion batteries A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also se ...
with a total capacity of 64.8Ah for use during eclipses. The power is fully regulated at 28 V, and the Terma power module (also used in ''
Rosetta Rosetta or Rashid (; ar, رشيد ' ; french: Rosette  ; cop, ϯⲣⲁϣⲓⲧ ''ti-Rashit'', Ancient Greek: Βολβιτίνη ''Bolbitinē'') is a port city of the Nile Delta, east of Alexandria, in Egypt's Beheira governorate. The R ...
'') is redundant. During routine phase, the spacecraft's power consumption is in the range of 450–550W.


Avionics

Attitude control (3-axis stabilization) is achieved using two 3-axis inertial measurement units, a set of two star cameras and two
Sun sensor A sun sensor is a navigational instrument used by spacecraft to detect the position of the sun. Sun sensors are used for attitude control, solar array pointing, gyro updating, and fail-safe recovery. In addition to spacecraft, sun sensors fin ...
s,
gyroscope A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rot ...
s,
accelerometer An accelerometer is a tool that measures proper acceleration. Proper acceleration is the acceleration (the rate of change of velocity) of a body in its own instantaneous rest frame; this is different from coordinate acceleration, which is acce ...
s, and four 12 N·m·s
reaction wheel A reaction wheel (RW) is used primarily by spacecraft for three-axis attitude control, and does not require rockets or external applicators of torque. They provide a high pointing accuracy, and are particularly useful when the spacecraft must be ...
s. Pointing accuracy is 0.04 degree with respect to the inertial reference frame and 0.8 degree with respect to the Mars orbital frame. Three on-board systems help ''Mars Express'' maintain a very precise pointing accuracy, which is essential to allow the spacecraft to use some of the science instruments.


Communications

The communications subsystem is composed of 3 antennas: A 1.6 m diameter parabolic dish high-gain antenna and two omnidirectional antennas. The first one provide links (telecommands uplink and telemetry downlink) in both
X-band The X band is the designation for a band of frequencies in the microwave radio region of the electromagnetic spectrum. In some cases, such as in communication engineering, the frequency range of the X band is rather indefinitely set at approxi ...
(8.4 GHz) and
S-band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave radio band, band of the electromagnetic spectrum covering frequency, frequencies from 2 to 4 gigahertz (GHz). Thus it c ...
(2.1 GHz) and is used during nominal science phase around Mars. The low gain antennas are used during launch and early operations to Mars and for eventual contingencies once in orbit. Two Mars lander relay UHF antennas are mounted on the top face for communication with the ''Beagle 2'' or other landers, using a Melacom transceiver.


Earth stations

Although communications with Earth were originally scheduled to take place with the ESA 35-meter wide Ground Station in New Norcia (Australia) New Norcia Station, the mission profile of progressive enhancement and science return flexibility have triggered the use of the ESA ESTRACK Ground Stations in
Cebreros Station Cebreros Station (also known as DSA 2 or Deep Space Antenna 2) is a European Space Agency, ESTRACK radio antenna station for communication with spacecraft, located about 10 km east of Cebreros and 90 km from Madrid, Spain, operated by th ...
,
Madrid Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a metropolitan area population of approximately 6.7 million. It is the second-largest city in the European Union (EU), and ...
, Spain and Malargüe Station,
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the List of South American countries by area, second-largest ...
. In addition, further agreements with NASA
Deep Space Network The NASA Deep Space Network (DSN) is a worldwide network of American spacecraft communication ground segment facilities, located in the United States (California), Spain (Madrid), and Australia (Canberra), that supports NASA's interplanetary ...
have made possible the use of American stations for nominal mission planning, thus increasing complexity but with a clear positive impact in scientific returns. This inter-agency cooperation has proven effective, flexible and enriching for both sides. On the technical side, it has been made possible (among other reasons) thanks to the adoption of both Agencies of the Standards for Space Communications defined in CCSDS.


Thermal

Thermal control is maintained through the use of radiators, multi-layer insulation, and actively controlled heaters. The spacecraft must provide a benign environment for the instruments and on-board equipment. Two instruments, PFS and OMEGA, have infrared detectors that need to be kept at very low temperatures (about −180 °C). The sensors on the camera (HRSC) also need to be kept cool. But the rest of the instruments and on-board equipment function best at room temperatures (10–20 °C). The spacecraft is covered in gold-plated aluminium-tin alloy thermal blankets to maintain a temperature of 10–20 °C inside the spacecraft. The instruments that operate at low temperatures to be kept cold are thermally insulated from this relatively high internal temperature, and emit excess heat into space using attached radiators.


Control unit and data storage

The spacecraft is run by two Control and Data management Units with 12 gigabits of solid state mass memory for storage of data and housekeeping information for transmission. The on-board computers control all aspects of the spacecraft functioning including switching instruments on and off, assessing the spacecraft orientation in space and issuing commands to change it. Another key aspect of the ''Mars Express'' mission is its
artificial intelligence Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech ...
tool (MEXAR2). The primary purpose of the AI tool is the scheduling of when to download various parts of the collected scientific data back to Earth, a process which used to take ground controllers a significant amount of time. The new AI tool saves operator time, optimizes bandwidth use on the DSN, prevents data loss, and allows better use of the DSN for other space operations as well. The AI decides how to manage the spacecraft's 12 gigabits of storage memory, when the DSN will be available and not be in use by another mission, how to make the best use of the DSN bandwidth allocated to it, and when the spacecraft will be oriented properly to transmit back to Earth.


Lander

The ''
Beagle 2 The ''Beagle 2'' is an inoperative British Mars lander that was transported by the European Space Agency's 2003 ''Mars Express'' mission. It was intended to conduct an astrobiology mission that would have looked for evidence of past life on Mar ...
'' lander objectives were to characterize the landing site geology, mineralogy, and geochemistry, the physical properties of the atmosphere and surface layers, collect data on Martian meteorology and climatology, and search for possible signatures of
life Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from that which does not, and is defined by the capacity for growth, reaction to stimuli, metabolism, energy ...
. However, the landing attempt was unsuccessful and the lander was declared lost. A Commission of Inquiry on ''Beagle 2'' identified several possible causes, including airbag problems, severe shocks to the lander's electronics which had not been simulated adequately before launch, and problems with parts of the landing system colliding; but was unable to reach any firm conclusions. The spacecraft's fate remained a mystery until it was announced in January 2015 that NASA's Mars Reconnaissance Orbiter, using HiRISE, had found the probe intact on the surface of Mars. It was then determined that an error had prevented two of the spacecraft's four solar panels from deploying, blocking the spacecraft's communications. ''Beagle 2'' was the first British and first European probe to achieve a landing on Mars.


Scientific instruments

The scientific objectives of the ''Mars Express'' payload are to obtain global high-resolution photo-geology (10 m resolution), mineralogical mapping (100 m resolution) and mapping of the atmospheric composition, study the subsurface structure, the global atmospheric circulation, and the interaction between the atmosphere and the subsurface, and the atmosphere and the interplanetary medium. The total mass budgeted for the science payload is 116 kg. The payload scientific instruments are: * 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. Is mounted inside pointing out the top face. Instrument mass: 28.6 kg * Ultraviolet and Infrared Atmospheric Spectrometer (SPICAM) - France - Assesses elemental composition of the atmosphere. Is mounted inside pointing out the top face. Instrument mass: 4.7 kg * Sub-Surface Sounding Radar Altimeter ( MARSIS) - Italy - A radar
altimeter An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. The measurement of altitude is called altimetry, which is related to the term bathymetry, the measurement of depth under water. The m ...
used to assess composition of sub-surface aimed at search for frozen water. Is mounted in the body and is nadir pointing, and also incorporates the two 20 m antennas. Instrument mass: 13.7 kg * Planetary Fourier Spectrometer ( PFS) - Italy - Makes observations of atmospheric temperature and pressure (observations suspended in September 2005). Is mounted inside pointing out the top face and is currently working. Instrument mass: 30.8 kg * Analyzer of Space Plasmas and Energetic Atoms
ASPERA
- Sweden - Investigates interactions between upper atmosphere and solar wind. Is mounted on the top face. Instrument mass: 7.9 kg * High Resolution Stereo Camera (HRSC) - Germany - Produces color images with up to 2 m resolution. Is mounted inside the spacecraft body, aimed through the top face of the spacecraft, which is nadir pointing during Mars operations. Instrument mass: 20.4 kg * Mars Express Lander Communications (MELACOM) - UK - Allows ''Mars Express'' to act as a communication relay for landers on the Martian surface. (Has been used on both Mars Exploration Rovers, and was used to support the landing of NASA's ''Phoenix'' mission) * Mars Radio Science Experiment (MaRS) - Uses radio signals to investigate atmosphere, surface, subsurface, gravity and solar corona density during solar conjunctions. It uses the communications subsystem itself. * Visual Monitoring Camera, a small camera to monitor the lander ejection.


Scientific discoveries and important events

For more than 20,000 orbits, ''Mars Express'' payload instruments have been nominally and regularly operated. The HRSC camera has been consistently mapping the Martian surface with unprecedented resolution and has acquired multiple images.


2004

* January 23 :: ESA announced the discovery of water ice in the south polar ice cap, using data collected by the OMEGA instrument. * January 28 :: ''Mars Express'' orbiter reaches final science orbit altitude around Mars. * March 17 :: Orbiter detects polar ice caps that contain 85%
carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
(CO2) ice and 15% water ice. * March 30 :: A press release announces that the orbiter has detected methane in the Martian atmosphere. Although the amount is small, about 10 parts in a thousand million, it has excited scientists to question its source. Since methane is removed from the Martian atmosphere very rapidly, there must be a current source that replenishes it. Because one of the possible sources could be microbial life, it is planned to verify the reliability of these data and especially watch for difference in the concentration in various places on Mars. It is hoped that the source of this gas can be discovered by finding its location of release. * April 28 :: ESA announced that the deployment of the boom carrying the radar-based MARSIS antenna was delayed. It described concerns with the motion of the boom during deployment, which can cause the spacecraft to be struck by elements of it. Further investigations are planned to make sure that this will not happen. * July 15 :: Scientists working with the PFS instrument announced that they tentatively discovered the spectral features of the compound
ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous ...
in the Martian atmosphere. Just like methane discovered earlier (see above), ammonia breaks down rapidly in Mars' atmosphere and needs to be constantly replenished. This points towards the existence of active life or geological activity; two contending phenomena whose presence so far have remained undetected.


2005

* 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. * February 8 :: The delayed deployment of the MARSIS antenna has been given a green light by ESA. It is planned to take place in early May 2005. * May 5 :: The first boom of the MARSIS antenna was successfully deployed. At first, there was no indication of any problems, but later it was discovered that one segment of the boom did not lock. The deployment of the second boom was delayed to allow for further analysis of the problem. * May 11 :: Using the Sun's heat to expand the segments of the MARSIS antenna, the last segment locked in successfully. * June 14 :: The second boom was deployed, and on June 16 ESA announced it was a success. * June 22 :: ESA announces that MARSIS is fully operational and will soon begin acquiring data. This comes after the deployment of the third boom on June 17, and a successful transmission test on June 19.


2006

* September 21 :: The High Resolution Stereo Camera (HRSC) has obtained images of the Cydonia region, the location of the famous " Face on Mars". The massif became famous in a photo taken in 1976 by the American ''Viking 1'' Orbiter. The image recorded with a ground resolution of approximately 13.7 metres per pixel. * September 26 :: The ''Mars Express'' spacecraft emerged from an unusually demanding eclipse introducing a special, ultra-low-power mode nicknamed 'Sumo' - an innovative configuration aimed at saving the power necessary to ensure spacecraft survival. ::This mode was developed through teamwork between ESOC mission controllers, principal investigators, industry, and mission management. * October :: In October 2006 the ''Mars Express'' spacecraft encountered a superior solar conjunction (alignment of Earth-Sun-Mars-orbiter). The angle Sun-Earth-orbiter reached a minimum on October 23 at 0.39° at a distance of 2.66 AU. Operational measures were undertaken to minimize the impact of the link degradation, since the higher density of electrons in the solar plasma heavily impacts the radio frequency signal. * December :: Following the loss of NASA's ''
Mars Global Surveyor ''Mars Global Surveyor'' (MGS) was an American robotic space probe developed by NASA's Jet Propulsion Laboratory and launched November 1996. MGS was a global mapping mission that examined the entire planet, from the ionosphere down through t ...
'' (MGS), ''Mars Express'' team was requested to perform actions in the hopes of visually identifying the American spacecraft. Based on last
ephemeris In astronomy and celestial navigation, an ephemeris (pl. ephemerides; ) is a book with tables that gives the trajectory of naturally occurring astronomical objects as well as artificial satellites in the sky, i.e., the position (and possibly ...
of MGS provided by JPL, the on-board high definition HRSC camera swept a region of the MGS orbit. Two attempts were made to find the craft, both unsuccessful.


2007

* January :: First agreements with NASA undertaken for the support by ''Mars Express'' on the landing of the American lander ''Phoenix'' in May 2008. * February :: The small camera VMC (used only once to monitor the lander ejection) was recommissioned and first steps were taken to offer students the possibility to participate in a campaign "Command Mars Express Spacecraft and take your own picture of Mars". * February 23 :: As result of the science return, the Science Program Committee (SPC) granted a mission extension until May 2009. * June 28 :: The High Resolution Stereo Camera (HRSC) has produced images of key tectonic features in
Aeolis Mensae Aeolis Mensae is a tableland feature in the northwest Aeolis quadrangle of Mars. Its location is centered at 2.9° south latitude and 219.6° west longitude, in the Martian dichotomy, transition zone between the Martian highlands and lowlands. ...
.


2008

* The Mars Express Team was the winner of the
Sir Arthur Clarke Award The Sir Arthur Clarke Award is a British award given annually since 2005 in recognition of notable contributions to space exploration, particularly British achievements. Nominations for the awards are made by members of the public, with shortlis ...
for Best Team Achievement.


2009

* February 4 :: The ESA's Science Programme Committee has extended the operations of ''Mars Express'' until December 31, 2009. *October 7 ::ESA's Science Programme Committee has approved the extension of mission operations for ''Mars Express'' until December 31, 2012.


2010

*March 5 ::Flyby of Phobos to measure Phobos' gravity.


2011

*August 13 ::Safe mode following a Solid-State Mass Memory problem. *August 23 ::Solid-State Mass Memory problem. *September 23 ::Safe mode following a Solid-State Mass Memory problem. *October 11 ::Solid-State Mass Memory problem. *October 16 ::Safe mode following a Solid-State Mass Memory problem. *November 24 ::Science operations are resumed using the Short Mission Timeline and Command Files instead of the Long Time Line resident on the suspect Solid-State Mass Memory.


2012

* February 16 ::Resumes full science operations. There is still enough fuel for up to 14 additional years of operation. * July ::Solar corona studied with radio waves. * August 5/6 :: Assisted US probes ''
Mars Odyssey ''2001 Mars Odyssey'' is a robotic spacecraft orbiting the planet Mars. The project was developed by NASA, and contracted out to Lockheed Martin, with an expected cost for the entire mission of US$297 million. Its mission is to use spectro ...
'' and '' Mars Reconnaissance Orbiter'' in data collection and transfer on the
Mars Science Laboratory Mars Science Laboratory (MSL) is a robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity'', a Mars rover, in Gale Crater on August 6, 2012. The overall objectives include investigati ...
landing.


2013

*''Mars Express'' produced a near-complete topographical map of Mars' surface. *December 29 ::''Mars Express'' performed the closest flyby to date of Phobos


2014

* October 19 ::ESA reported ''Mars Express'' was healthy after the Comet Siding Spring flyby of Mars on October 19, 2014 — as were all NASA Mars orbiters and ISRO's orbiter, the
Mars Orbiter Mission The Mars Orbiter Mission (MOM), also called ''Mangalyaan'', was a space probe orbiting Mars since 24 September 2014. It was launched on 5 November 2013 by the Indian Space Research Organisation (ISRO). It was India's first interplanetary mis ...
.


2016

* October 19 :: Assisted with data collection and transfer for the
Schiaparelli EDM lander Schiaparelli may refer to: * Schiaparelli (surname), Italian surname * Schiaparelli (fashion house), founded by Elsa Schiaparelli and later revived Astronomy * Schiaparelli (lunar crater), a relatively small crater in the LQ10 (Seleucus) quadran ...
landing.


2017

*June 19 ::Takes noted image spanning from the North pole up to
Alba Mons Alba Mons (formerly and still occasionally known as Alba Patera, a term that has since been restricted to the volcano's summit caldera; also initially known as the Arcadia ring) is a volcano located in the northern Tharsis region of the planet Ma ...
and even farther south. The image was released in December 20, 2017 and was captured by HRSC.


2018

*Activated new AOCMS software which includes a gyroless attitude estimator to prolong the lifetime of the spacecraft's laser gyros *July 2018, a discovery is reported based on MARSIS
radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...
studies, of a subglacial lake on
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...
, below the southern polar ice cap, and about wide, the first known stable body of water on Mars. * December 2018 ''Mars Express'' relays images of the 80-kilometer wide Korolev Crater filled with approximately 2200 cubic kilometers of water ice on the Martian surface. Based on further evidence the crater ice is still part of much vaster ice resources at Mars poles.


2019

*Based on data from the HRSC camera, there is geological evidence of an ancient planet-wide groundwater system.


2020

*Sept 2020, a discovery is reported based on MARSIS radar studies, of a three more subglacial lakes on Mars, below the southern polar ice cap. The size of the first lake found, and the largest, has been corrected to wide. It is surrounded by 3 smaller lakes, each a few kilometres wide.


2021

* Investigation of
orographic Orography is the study of the topographic relief of mountains, and can more broadly include hills, and any part of a region's elevated terrain. Orography (also known as ''oreography'', ''orology'' or ''oreology'') falls within the broader disci ...
cloud extending from Arsia Mons volcano * An experiment to test whether the Mars Express and TGO lander relay communications radio could be used to perform occultation radio science * Tests of data relay from the CNSA Zhurong Rover


2022

* The onboard software of the MARSIS experiment was upgraded in order to improve the performance of the instrument.


Payload principal investigators links

* HRS
Mars Express FU Berlin

MARSIS
Uni Roma "La Sapienza"
PFS
IFSI/INAF * SPICAM * OMEG
Institut Astrophysique Spatial


Qinetiq

Uni Köln
ASPERA


See also

* * * *
List of Mars orbiters The following table is a list of Mars orbiters, consisting of space probes which were launched from Earth and are currently orbiting Mars. As of February 2021, there have been 18 spacecraft missions operating in Mars' orbit, 8 of which are cu ...
* List of missions to Mars * *


References


External links


''ESA Mars Express'' project
– official website
''ESA Mars Express'' project
– scientific website


Mars Express Mission Profile
b
NASA's Solar System Exploration


* ttp://mars.jpl.nasa.gov/express/gallery/artwork/ NASA Art Gallery of Mars Express
Can show present over head position of Mars Express
{{Portal bar, Solar System
Express Express or EXPRESS may refer to: Arts, entertainment, and media Films * '' Express: Aisle to Glory'', a 1998 comedy short film featuring Kal Penn * '' The Express: The Ernie Davis Story'', a 2008 film starring Dennis Quaid Music * ''Express'' ...
Express Express or EXPRESS may refer to: Arts, entertainment, and media Films * '' Express: Aisle to Glory'', a 1998 comedy short film featuring Kal Penn * '' The Express: The Ernie Davis Story'', a 2008 film starring Dennis Quaid Music * ''Express'' ...
Mars Express Mars Express Geography of Mars Attached spacecraft Spacecraft launched by Soyuz-FG rockets