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Mars Express
CG image of Mars Express
Mission typeMars orbiter
COSPAR ID2003-022A Edit this at Wikidata
SATCAT no.27816
Mission durationElapsed:
20 years, 2 months and 13 days since launch
19 years, 7 months and 21 days at Mars
Spacecraft properties
Launch mass1,123 kg[1]
Dry mass666 kg (1,468 lb)
Power460 watts
Start of mission
Launch dateJune 2, 2003, 17:45 (2003-06-02UTC17:45Z) UTC
Launch siteBaikonur 31/6
Orbital parameters
Reference systemAreocentric
Periareion altitude298 km (185 mi)
Apoareion altitude10,107 km (6,280 mi)
Inclination86.3 degrees
Period7.5 hours
Mars orbiter
Spacecraft componentMars Express
Orbital insertionDecember 25, 2003, 03:00 UTC
MSD 46206 08:27 AMT
Mars lander
Spacecraft componentBeagle 2
Landing dateDecember 25, 2003, 02:54 UTC
Mars Express mission insignia
ESA Solar System insignia for the Mars Express mission  

Mars Express is a space exploration mission being conducted by the European Space Agency (ESA). The Mars Express mission is exploring the planet Mars, and is the first planetary mission attempted by the agency.[2] "Express" originally referred to the speed and efficiency with which the spacecraft was designed and built.[3] 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,[4] a lander 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 with the interplanetary medium.[4]

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 March 7, 2023 and runs until December 31, 2026.[5]

Some of the instruments on the orbiter, including the camera systems and some spectrometers, reuse designs from the failed launch of the Russian Mars 96 mission in 1996[2] (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 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.[6]

Arriving at Mars in 2003, 19 years, 7 months and 21 days 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.

Mission profile and timeline overview

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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 150 million.[7][8] 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:


Animation of Mars Express's trajectory around Sun
  Mars Express ·   Sun ·   Earth  ·   Mars

The spacecraft was launched on June 2, 2003, at 23:45 local time (17:45 UT, 1:45 p.m. EDT) from Baikonur Cosmodrome in Kazakhstan, 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 panels 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 flares ever recorded.

Lander jettison

The Beagle 2 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 Mars Odyssey 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.[9]

Orbit insertion

Animation of Mars Express's trajectory around Mars from December 25, 2003, to January 1, 2010
   Mars Express ·   Mars
Image of Mars Express in orbit, taken by Mars Global Surveyor
Artist's impression of the expected appearance of Mars Express at the time of the Mars Global Surveyor image

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

Illustration of Mars Express with MARSIS antenna deployed

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 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 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,[10][11] and 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. 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 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


The Mars Express orbiter is a cube-shaped spacecraft with two solar panel 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 antennas extend from opposite side faces perpendicular to the solar panels as part of the radar sounder.[12]


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.[12]

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 launch vehicle.


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 460 W. This loss of power does significantly impact the science return of the mission. Power is stored in three lithium-ion batteries with a total capacity of 64.8 Ah for use during eclipses. The power is fully regulated at 28 V, and the Terma power module (also used in Rosetta) is redundant.[13][14] During routine phase, the spacecraft's power consumption is in the range of 450–550 W.[15]


Attitude control (3-axis stabilization) is achieved using two 3-axis inertial measurement units, a set of two star cameras and two Sun sensors, gyroscopes, accelerometers, and four 12 N·m·s reaction wheels. 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.


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 (8.4 GHz) and S-band (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.[16][citation needed]

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, Madrid, Spain and Malargüe Station, Argentina.

In addition, further agreements with NASA Deep Space Network 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 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.[12]

Control unit and data storage

The spacecraft is run by two Control and Data management Units with 12 gigabits[12] 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 tool (MEXAR2).[17] 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.[17][18]


A replica of the Beagle 2 lander component of Mars Express at the Science Museum London

The Beagle 2 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. However, the landing attempt was unsuccessful and the lander was declared lost. A Commission of Inquiry on Beagle 2[9] 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.[19] The payload scientific instruments are:[20]

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.


ESA announced the discovery of water ice in the south polar ice cap, using data collected by the OMEGA instrument.
Mars Express orbiter reaches final science orbit altitude around Mars.
Orbiter detects polar ice caps that contain 85% carbon dioxide (CO2) ice and 15% water ice.[24]
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.[25]
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.
Scientists working with the PFS instrument announced that they tentatively discovered the spectral features of the compound ammonia 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.[26]


The delayed deployment of the MARSIS antenna has been given a green light by ESA.[29] It is planned to take place in early May 2005.
The first boom of the MARSIS antenna was successfully deployed.[30] At first, there was no indication of any problems, but later it was discovered that one segment of the boom did not lock.[31] The deployment of the second boom was delayed to allow for further analysis of the problem.
Using the Sun's heat to expand the segments of the MARSIS antenna, the last segment locked in successfully.[32]
The second boom was deployed, and on June 16 ESA announced it was a success.[33]
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.[34]


External image
image icon Cydonia region
ESA/DLR Credit — 13.7 m/pixel
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.[35]
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.[36]
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.[37]
Following the loss of NASA's Mars Global Surveyor (MGS), Mars Express team was requested to perform actions in the hopes of visually identifying the American spacecraft. Based on last ephemeris 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.


Greyscale view of Phobos over Mars, 2007
First agreements with NASA undertaken for the support by Mars Express on the landing of the American lander Phoenix in May 2008.
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".
As result of the science return, the Science Program Committee (SPC) granted a mission extension until May 2009.[38]
The High Resolution Stereo Camera (HRSC) has produced images of key tectonic features in Aeolis Mensae.[39]



The ESA's Science Programme Committee has extended the operations of Mars Express until December 31, 2009.[40]
ESA's Science Programme Committee has approved the extension of mission operations for Mars Express until December 31, 2012.[41]


Flyby of Phobos to measure Phobos' gravity.[42]


Safe mode following a Solid-State Mass Memory problem.[43]
Solid-State Mass Memory problem.[43]
Safe mode following a Solid-State Mass Memory problem.[43]
Solid-State Mass Memory problem.[43]
Safe mode following a Solid-State Mass Memory problem.[43]
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.[44]


Resumes full science operations. There is still enough fuel for up to 14 additional years of operation.[45]
Solar corona studied with radio waves.[46]
Assisted US probes Mars Odyssey and Mars Reconnaissance Orbiter in data collection and transfer on the Mars Science Laboratory landing.


Mars Express performed the closest flyby to date of Phobos
Rabe crater, 2014


ESA reported Mars Express was healthy after the Comet Siding Spring flyby of Mars on October 19, 2014[48] — as were all NASA Mars orbiters[49] and ISRO's orbiter, the Mars Orbiter Mission.[50]


Assisted with data collection and transfer for the Schiaparelli EDM lander landing.
South pole of Mars by Mars Express, 2015


Takes noted image spanning from the North pole up to Alba Mons and even farther south.[51] The image was released in December 20, 2017 and was captured by HRSC.[51][52]


Further information: Water on Mars






To celebrate the 20th anniversary of the spacecraft's launch, a livestream of images from the Visual Monitoring Camera was streamed online, marking the first livestream direct from Mars.[68]

Payload principal investigators links

See also


  1. ^ "Mars Express". NASA Space Science Data Coordinated Archive. Retrieved November 30, 2022.
  2. ^ a b Howell, Elizabeth (July 26, 2018). "European Space Agency's Mars Express". Retrieved April 1, 2023.
  3. ^ "Mars Express Frequently Asked Questions". ESA. February 18, 2009. Retrieved March 28, 2016.
  4. ^ a b "NASA - NSSDCA - Spacecraft - Details". National Aeronautics and Space Administration. Retrieved April 1, 2023.
  5. ^ "Extended life for ESA's science missions". ESA. March 7, 2023. Retrieved March 20, 2023.
  6. ^ Announcement by the European Space Agency on the launch of the Mars Express space probe: "Mars en route for the red planet". (2004). Historic documents of 2003.Washington, DC: CQ Press. Retrieved from[permanent dead link]
  7. ^ "Mars Express: Summary". European Space Agency. March 29, 2011.
  8. ^ "Mars Express". NSSDC ID: 2003-022A. NASA. Retrieved December 7, 2018.
  9. ^ a b "Beagle 2 ESA/UK Commission of Inquiry". April 5, 2004. Retrieved March 29, 2016.
  10. ^ "Glitch strikes Mars Express' radar boom – space – May 9, 2005 – New Scientist". Archived from the original on February 5, 2008.
  11. ^ "Mars Express' kinky radar straightened out – space – May 12, 2005 – New Scientist". Archived from the original on February 6, 2008.
  12. ^ a b c d "The spacecraft / Mars Express". ESA. October 10, 2005. Retrieved March 29, 2016.
  13. ^ Stage, Mie (January 19, 2014). "Terma-elektronik vækker rumsonde fra årelang dvale". Ingeniøren. Retrieved March 29, 2016.
  14. ^ Jensen, H.; Laursen, J. (2002). "Power Conditioning Unit for Rosetta/Mars Express". Space Power. Astrophysics Data System. 502: 249. Bibcode:2002ESASP.502..249J.
  15. ^ "MEX — ASI-PROC". Planetary Radar Operational Center. March 29, 2016. Archived from the original on April 13, 2016. Retrieved March 29, 2016.
  16. ^ "QinetiQ to put Mars in the picture". Qinetiq. Archived from the original on August 31, 2006. Retrieved March 29, 2016. Consisting of a lightweight bespoke transponder and transceiver weighing less than 650 grams, the system will provide the 10,000-kilometre UHF radio communications link between the Mars Express orbiter and Beagle-2 lander.
  17. ^ a b "Artificial intelligence boosts science from Mars". ESA. April 29, 2008. Retrieved March 29, 2016.
  18. ^ Cesta, Amedeo (2007). "Mexar2: AI Solves Mission Planner Problems" (PDF). IEEE Intelligent Systems. 22 (4): 12–19. doi:10.1109/MIS.2007.75. S2CID 14477705. Archived from the original (PDF) on March 5, 2012. Retrieved December 7, 2011.
  19. ^ Andrew Wilson; Agustin Chicarro (2004). ESA SP-1240: Mars Express: the scientific payload. Noordwijk, Netherlands: ESA Publications Division. ISBN 978-92-9092-556-9.
  20. ^ "Mars Express orbiter instruments". ESA. November 30, 2005. Retrieved March 29, 2016.
  21. ^ Bibring JP, Langevin Y, Mustard JF, Poulet F, Arvidson R, Gendrin A, Gondet B, Mangold N, Pinet P, Forget F (2006). "Global mineralogical and aqueous mars history derived from OMEGA/Mars express data". Science. 312 (5772): 400–404. Bibcode:2006Sci...312..400B. doi:10.1126/science.1122659. PMID 16627738.
  22. ^ a b c d e f Chicarro, A.F. (2003). MARS EXPRESS MISSION: Overview and Scientific Observations (PDF) (Report). Retrieved March 29, 2016.
  23. ^ Peplow, Mark (September 7, 2005). "Martian methane probe in trouble". News@nature. Nature: news050905–10. doi:10.1038/news050905-10. Retrieved March 29, 2016.
  24. ^ "Water at Martian south pole". ESA. March 17, 2004. Retrieved March 29, 2016.
  25. ^ Formisano, V; Atreya, S; Encrenaz, T; Ignatiev, N; Giuranna, M (2004). "Detection of methane in the atmosphere of Mars". Science. 306 (5702): 1758–1761. Bibcode:2004Sci...306.1758F. doi:10.1126/science.1101732. PMID 15514118. S2CID 13533388.
  26. ^ "Water and methane maps overlap on Mars: a new clue?". ESA. September 20, 2004. Retrieved March 29, 2016.
  27. ^ Mustard, JF (2005). "Olivine and Pyroxene Diversity in the Crust of Mars". Science. 307 (5715): 1594–7. Bibcode:2005Sci...307.1594M. doi:10.1126/science.1109098. PMID 15718427. S2CID 15548016.
  28. ^ Bargery, AS; et al. (2006). "NEAR-INFRARED ANALYSIS OF TEMPE TERRA, OLYMPICA FOSSAE AND NILI FOSSAE FROM OMEGA DATA". Lunar and Planetary Science. XXXVII: 1684.
  29. ^ "Green light for deployment of ESA's Mars Express radar". ESA. February 8, 2005. Retrieved March 29, 2016.
  30. ^ "First Marsis radar boom deployed". BBC News Online. May 5, 2005. Retrieved March 29, 2016.
  31. ^ "Delay hits Mars radar deployment". BBC News Online. May 9, 2005. Retrieved March 29, 2016.
  32. ^ "First MARSIS boom successfully deployed". ESA. May 11, 2005. Retrieved March 29, 2016.
  33. ^ "Smooth deployment for second MARSIS antenna boom". ESA. June 16, 2005. Retrieved March 29, 2016.
  34. ^ "Mars Express radar ready to work". ESA. June 22, 2005. Retrieved March 29, 2016.
  35. ^ "Cydonia – the face on Mars". ESA. September 21, 2006. Retrieved March 29, 2016.
  36. ^ "Mars Express successfully powers through eclipse season". ESA. September 26, 2006. Retrieved March 29, 2016.
  37. ^ Morley, Trevor; Budnik, Frank. "EFFECTS ON SPACECRAFT RADIOMETRIC DATA AT SUPERIOR SOLAR CONJUNCTION" (PDF). European Space Operations Centre.
  38. ^ "The planetary adventure continues - Mars Express and Venus Express operations extended". ESA. February 27, 2007. Retrieved March 29, 2016.
  39. ^ "Tectonic signatures at Aeolis Mensae". ESA News. European Space Agency. June 28, 2007. Retrieved March 29, 2016.
  40. ^ "ESA extends missions studying Mars, Venus and Earth's magnetosphere". ESA. February 9, 2009. Retrieved March 29, 2016.
  41. ^ "Mission extensions approved for science missions". ESA. October 7, 2009. Retrieved March 29, 2016.
  42. ^ "Phobos Flyby Success". Space Fellowship. March 5, 2010. Archived from the original on February 21, 2014. Retrieved March 29, 2016.
  43. ^ a b c d e "Mars Express observations temporarily suspended". ESA. November 24, 2011. Retrieved March 29, 2016.
  44. ^ "Mars Express steadily returns to routine operation". ESA. November 24, 2011. Retrieved March 29, 2016.
  45. ^ Clark, Stephen (February 15, 2012). "Mars Express back in business at the red planet". Spaceflight Now. Retrieved March 29, 2016.
  46. ^ "Radio sounding of the solar corona with Mars Express". ESA. July 24, 2012. Retrieved March 29, 2016.
  47. ^ Gibney, Elizabeth (October 28, 2013). "Spectacular flyover of Mars". Nature News. Retrieved November 17, 2013.
  48. ^ Denis, Michel (October 20, 2014). "Spacecraft in great shape – our mission continues". European Space Agency. Retrieved October 21, 2014.
  49. ^ Webster, Guy; Brown, Dwayne; Jones, Nancy; Steigerwald, Bill (October 19, 2014). "All Three NASA Mars Orbiters Healthy After Comet Flyby". NASA. Retrieved October 20, 2014.
  50. ^ Staff (October 21, 2014). "I'm safe and sound, tweets MOM after comet sighting". The Hindu. Retrieved October 21, 2014.
  51. ^ a b "ESA Releases Stunning New Image of Mars | Space Exploration |". Breaking Science News | December 20, 2017.
  52. ^ "Relaunch explanation". NAV_NODE DLR Portal.
  53. ^ "Mars Express v2.0". Retrieved April 12, 2022.
  54. ^ Orosei, R.; et al. (July 25, 2018). "Radar evidence of subglacial liquid water on Mars". Science. 361 (6401): 490–493. arXiv:2004.04587. Bibcode:2018Sci...361..490O. doi:10.1126/science.aar7268. hdl:11573/1148029. PMID 30045881.
  55. ^ Chang, Kenneth; Overbye, Dennis (July 25, 2018). "A Watery Lake Is Detected on Mars, Raising the Potential for Alien Life - The discovery suggests that watery conditions beneath the icy southern polar cap may have provided one of the critical building blocks for life on the red planet". The New York Times. Retrieved July 25, 2018.
  56. ^ "Huge reservoir of liquid water detected under the surface of Mars". EurekAlert. July 25, 2018. Retrieved July 25, 2018.
  57. ^ "Liquid water 'lake' revealed on Mars". BBC News. July 25, 2018. Retrieved July 25, 2018.
  58. ^ "A winter wonderland in red and white – Korolev Crater on Mars". German Aerospace Center (DLR). Retrieved December 20, 2018.
  59. ^ Sample, Ian (December 21, 2018). "Mars Express beams back images of ice-filled Korolev crater". The Guardian. Retrieved December 21, 2018.
  60. ^ Salese, Francesco; Pondrelli, Monica; Neeseman, Alicia; Schmidt, Gene; Ori, Gian Gabriele (2019). "Geological Evidence of Planet‐Wide Groundwater System on Mars". Journal of Geophysical Research: Planets. 124 (2): 374–395. Bibcode:2019JGRE..124..374S. doi:10.1029/2018JE005802. PMC 6472477. PMID 31007995.
  61. ^ "First evidence of planet-wide groundwater system on Mars". ESA. Retrieved February 28, 2019.
  62. ^ Lauro, Sebastian Emanuel; Pettinelli, Elena; Caprarelli, Graziella; Guallini, Luca; Rossi, Angelo Pio; Mattei, Elisabetta; Cosciotti, Barbara; Cicchetti, Andrea; Soldovieri, Francesco; Cartacci, Marco; Di Paolo, Federico; Noschese, Raffaella; Orosei, Roberto (September 28, 2020). "Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data". Nature Astronomy. Springer Nature Limited. 5: 63–70. arXiv:2010.00870. doi:10.1038/s41550-020-1200-6. ISSN 2397-3366. S2CID 222125007.
  63. ^ Hernández-Bernal, J.; Sánchez-Lavega, A.; del Río-Gaztelurrutia, T.; Ravanis, E.; Cardesín-Moinelo, A.; Connour, K.; Tirsch, D.; Ordóñez-Etxeberria, I.; Gondet, B.; Wood, S.; Titov, D. (March 2021). "An Extremely Elongated Cloud over Arsia Mons Volcano on Mars: I. Life Cycle". Journal of Geophysical Research: Planets. 126 (3). arXiv:2103.03919. Bibcode:2021JGRE..12606517H. doi:10.1029/2020JE006517. ISSN 2169-9097. S2CID 232147554.
  64. ^ "ESA Mars orbiters: two-for-one science – Mars Express". Retrieved April 11, 2022.
  65. ^ "Mars Express keeps an ear out for Chinese rover – Mars Express". Retrieved April 11, 2022.
  66. ^ "Software upgrade for 19-year-old martian water-spotter". Retrieved July 2, 2022.
  67. ^ "This Mars Orbiter Is Finally Getting A Software Update From Windows 98". June 29, 2022. Retrieved July 2, 2022.
  68. ^ "Tune in for first Mars livestream". Retrieved June 2, 2023.

Map of Mars
Interactive image map of the global topography of Mars, overlaid with the position of Martian rovers and landers. Coloring of the base map indicates relative elevations of Martian surface.
Clickable image: Clicking on the labels will open a new article.
Legend:   Active (white lined, ※)  Inactive  Planned (dash lined, ⁂)
Beagle 2Beagle 2
Bradbury Landing
Deep Space 2
Deep Space 2
Rosalind FranklinRosalind Franklin
Mars 2Mars 2
Mars 3Mars 3
Mars 6Mars 6
Mars Polar Lander
Mars Polar Lander ↓
Schiaparelli EDM
Schiaparelli EDM
Viking 1
Viking 1
Viking 2Viking 2