Editing Mars Express (section)

== Timeline of notable discoveries and events ==
For more than 20,000 orbits, ''Mars Express'' payload instruments have been nominally and regularly operated. The [[High Resolution Stereo Camera|HRSC camera]] has been consistently mapping the Martian surface with unprecedented resolution and has acquired many images.

=== First decade ===

==== 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]] (CO<sub>2</sub>) ice and 15% water ice.<ref>{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Water_at_Martian_south_pole |title=Water at Martian South Pole |publisher=[[ESA]] |date=March 17, 2004 |access-date=March 29, 2016 }}</ref>

* March 30: A press release announces that the orbiter has detected [[Methane on Mars|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.<ref>{{cite journal |last1=Formisano |first1=V. |last2=Atreya |first2=S. |last3=Encrenaz |first3=T. |author3-link=Thérèse Encrenaz |last4=Ignatiev |first4=N. |last5=Giuranna |first5=M. |title=Detection of Methane in the Atmosphere of Mars |journal=[[Science (journal)|Science]] |date=2004 |volume=306 |pages=1758–1761 |doi=10.1126/science.1101732 |pmid=15514118 |issue=5702 |bibcode = 2004Sci...306.1758F |s2cid=13533388 |doi-access=free }}</ref>

* 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]] 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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Water_and_methane_maps_overlap_on_Mars_a_new_clue|title=Water and methane maps overlap on Mars: a new clue?|publisher=[[ESA]]|date=September 20, 2004|access-date=March 29, 2016}}</ref>

==== 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.<ref>{{cite journal |last1=Mustard |first1=JF |title=Olivine and Pyroxene Diversity in the Crust of Mars |journal=Science |date=2005 |volume=307 |issue=5715 |pages=1594–7 |doi=10.1126/science.1109098|pmid=15718427 |bibcode=2005Sci...307.1594M |s2cid=15548016 |doi-access=free }}</ref><ref>{{cite journal |last1=Bargery |first1=AS|display-authors=etal|title=NEAR-INFRARED ANALYSIS OF TEMPE TERRA, OLYMPICA FOSSAE AND NILI FOSSAE FROM OMEGA DATA |journal=Lunar and Planetary Science |date=2006 |volume=XXXVII |page=1684}}</ref>
* February 8: The delayed deployment of the MARSIS antenna, planned for early May 2005, has been given a green light by ESA.<ref name=":2">{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Green_light_for_deployment_of_ESA_s_Mars_Express_radar|title=Green light for deployment of ESA's Mars Express radar|publisher=[[ESA]]|date=February 8, 2005|access-date=March 29, 2016}}</ref>

* May 5: The first boom of the MARSIS antenna was successfully deployed.<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/sci/tech/4516535.stm|title=First Marsis radar boom deployed|work=[[BBC News Online]]|date=May 5, 2005|access-date=March 29, 2016}}</ref> At first, there was no indication of any problems, but later it was discovered that one segment of the boom did not lock.<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/sci/tech/4528763.stm|title=Delay hits Mars radar deployment|work=[[BBC News Online]]|date=May 9, 2005|access-date=March 29, 2016}}</ref> 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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Operations/First_MARSIS_boom_successfully_deployed|title=First MARSIS boom successfully deployed|publisher=[[ESA]]|date=May 11, 2005|access-date=March 29, 2016}}</ref>

* June 14: The second boom was deployed, and on June 16 ESA announced it was a success.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Operations/Smooth_deployment_for_second_MARSIS_antenna_boom|title=Smooth deployment for second MARSIS antenna boom|publisher=[[ESA]]|date=June 16, 2005|access-date=March 29, 2016}}</ref>

* 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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Mars_Express_radar_ready_to_work|title=Mars Express radar ready to work|publisher=[[ESA]]|date=June 22, 2005|access-date=March 29, 2016}}</ref>

==== 2006 ====
* September 21: The High Resolution Stereo Camera (HRSC) has obtained images of the [[Cydonia (region of Mars)|Cydonia region]], the location of the famous "[[Cydonia Mensae|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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Cydonia_-_the_face_on_Mars|title=Cydonia – the face on Mars|publisher=[[ESA]]|date=September 21, 2006|access-date=March 29, 2016}}</ref>

* 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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Mars_Express_successfully_powers_through_eclipse_season|title=Mars Express successfully powers through eclipse season|publisher=[[ESA]]|date=September 26, 2006|access-date=March 29, 2016}}</ref>

* 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 [[Astronomical unit|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.<ref>{{cite web|url=https://issfd.org/ISSFD_2007/10-3.pdf|title=EFFECTS ON SPACECRAFT RADIOMETRIC DATA AT SUPERIOR SOLAR CONJUNCTION|last1=Morley|first1=Trevor|last2=Budnik|first2=Frank|publisher=European Space Operations Centre}}</ref>

* December: 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.

==== 2007 ====
[[File:Phobos over Mars' limb by HRSC.jpg|thumb|Greyscale view of [[Phobos (moon)|Phobos]] over Mars, 2007 (ESA/DLR/FU Berl|388x388px]]
* January: First agreements with NASA undertaken for the support by ''Mars Express'' on the landing of the American lander [[Phoenix (spacecraft)|''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.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/The_planetary_adventure_continues_-_Mars_Express_and_Venus_Express_operations_extended|title=The planetary adventure continues - Mars Express and Venus Express operations extended|publisher=[[ESA]]|date=February 27, 2007|access-date=March 29, 2016}}</ref>

* June 28: The High Resolution Stereo Camera (HRSC) has produced images of key tectonic features in [[Aeolis Mensae]].<ref name="aeolis">{{cite web
| title = Tectonic signatures at Aeolis Mensae
| work =ESA News
| publisher =European Space Agency
| date =June 28, 2007
| url =http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Tectonic_signatures_at_Aeolis_Mensae
| access-date =March 29, 2016}}</ref>

==== 2008 ====
* In March 2008, the ''Mars Express'' Team was the winner of the [[Sir Arthur Clarke Award]] for Best Team Achievement.<ref>{{Cite web |title=Sir Arthur Clarke Awards |url=https://www.bis-space.com/what-we-do/honours-and-awards/arthurs/ |access-date=2025-05-25 |website=The British Interplanetary Society |language=en-GB}}</ref>
* During a [[Phobos (moon)|Phobos]] flyby on 23 July 2008, ''Mars Express'' observed backscattering of [[solar wind]] protons at Phobos, a process previously reported at the Earth's [[Moon]], suggesting that it is common at airless bodies covered by [[regolith]].<ref>{{Cite journal |last=Futaana |first=Y. |last2=Barabash |first2=S. |last3=Holmström |first3=M. |last4=Fedorov |first4=A. |last5=Nilsson |first5=H. |last6=Lundin |first6=R. |last7=Dubinin |first7=E. |last8=Fränz |first8=M. |date=2010 |title=Backscattered solar wind protons by Phobos |url=https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010JA015486 |journal=Journal of Geophysical Research: Space Physics |language=en |volume=115 |issue=A10 |doi=10.1029/2010JA015486 |issn=2156-2202}}</ref> The next such observation occurred in January 2016.<ref>{{Cite journal |last=Futaana |first=Yoshifumi |last2=Holmström |first2=Mats |last3=Fedorov |first3=Andrey |last4=Barabash |first4=Stas |date=2021 |title=Does Phobos Reflect Solar Wind Protons? Mars Express Special Flyby Operations With and Without the Presence of Phobos |url=https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021JE006969 |journal=Journal of Geophysical Research: Planets |language=en |volume=126 |issue=11 |pages=e2021JE006969 |doi=10.1029/2021JE006969 |issn=2169-9100}}</ref>

==== 2009 ====
* February 4: The ESA's Science Programme Committee has extended the operations of ''Mars Express'' until December 31, 2009.<ref>{{cite web|url=http://sci.esa.int/solar-system/44174-mars-express-venus-express-cluster-missions-extended/|title=ESA extends missions studying Mars, Venus and Earth's magnetosphere|publisher=[[ESA]]|date=February 9, 2009|access-date=March 29, 2016}}</ref>

*October 7: ESA's Science Programme Committee has approved the extension of mission operations for ''Mars Express'' until December 31, 2012.<ref>{{cite web|url=http://sci.esa.int/director-desk/45685-mission-extensions-approved-for-science-missions/|title=Mission extensions approved for science missions|publisher=[[ESA]]|date=October 7, 2009|access-date=March 29, 2016}}</ref>
[[File:Orcus Patera by HRSC.jpg|thumb|[[Orcus Patera]] on Mars imaged by the [[High Resolution Stereo Camera|HRSC]] instrument aboard ''Mars Express'', 2010]]

==== 2010 ====
*March 5: Flyby of [[Phobos (moon)|Phobos]] to measure Phobos' gravity.<ref>{{cite news|url=http://spacefellowship.com/news/art18911/phobos-flyby-success.html|title=Phobos Flyby Success|work=[[Space Fellowship]]|date=March 5, 2010|access-date=March 29, 2016|archive-url=https://web.archive.org/web/20140221231830/http://spacefellowship.com/news/art18911/phobos-flyby-success.html|archive-date=February 21, 2014 }}</ref>

==== 2011 ====
*August 13: Safe mode following a Solid-State Mass Memory problem.<ref name="ESASCi">{{cite web|url=http://sci.esa.int/mars-express/49549-mars-express-observations-temporarily-suspended/|title=Mars Express observations temporarily suspended|publisher=[[ESA]]|date=November 24, 2011|access-date=March 29, 2016}}</ref>

*August 23: Solid-State Mass Memory problem.<ref name="ESASCi" />

*September 23: Safe mode following a Solid-State Mass Memory problem.<ref name="ESASCi" />

*October 11: Solid-State Mass Memory problem.<ref name="ESASCi" />

*October 16: Safe mode following a Solid-State Mass Memory problem.<ref name="ESASCi" />

*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.<ref name="ESASCi2">{{cite web|url=http://www.esa.int/Our_Activities/Operations/Mars_Express_steadily_returns_to_routine_operation|title=Mars Express steadily returns to routine operation|publisher=[[ESA]]|date=November 24, 2011|access-date=March 29, 2016}}</ref>

==== 2012 ====
* February 16: Resumes full science operations. There is still enough fuel for up to 14 additional years of operation.<ref>{{cite web|url=http://spaceflightnow.com/news/n1202/15marsexpress/|title=Mars Express back in business at the red planet|publisher=Spaceflight Now|first=Stephen|last=Clark|date=February 15, 2012|access-date=March 29, 2016}}</ref>
* In March 2012, a paper was published in [[JGR Planets|''JGR Planets'']] documenting the first detection of a faint infrared glow above the winter poles of Mars. This discovery was based on ''Mars Express''' OMEGA observations from 2004, 2005, and 2006.<ref>{{Cite web |title=ESA Science & Technology - A glow in the Martian night throws light on atmospheric circulation |url=https://sci.esa.int/web/mars-express/-/50198-a-glow-in-the-martian-night-throws-light-on-atmospheric-circulation |access-date=2025-05-18 |website=sci.esa.int |language=en-US}}</ref><ref>{{Cite journal |last1=Bertaux |first1=J. L. |last2=Gondet |first2=B. |last3=Lefèvre |first3=F. |last4=Bibring |first4=J. P. |last5=Montmessin |first5=F. |date=2012 |title=First detection of O 2 1.27 μ m nightglow emission at Mars with OMEGA/MEX and comparison with general circulation model predictions |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2011JE003890 |journal=Journal of Geophysical Research: Planets |language=en |volume=117 |issue=E11 |doi=10.1029/2011JE003890 |issn=0148-0227}}</ref>

* July: Solar corona studied with radio waves.<ref>{{cite web|url=http://sci.esa.int/mars-express/50629-radio-sounding-of-the-solar-corona-with-mars-express/|title=Radio sounding of the solar corona with Mars Express|publisher=[[ESA]]|date=July 24, 2012|access-date=March 29, 2016}}</ref>

* August 5/6: Assisted US probes ''[[Mars Odyssey]]'' and ''[[Mars Reconnaissance Orbiter]]'' in data collection and transfer on the [[Mars Science Laboratory]] landing.

==== 2013 ====
*''Mars Express'' produced a near-complete topographical map of Mars' surface.<ref>{{cite news | first1 = Elizabeth |last1=Gibney | title = Spectacular flyover of Mars | date = October 28, 2013 | url = http://www.nature.com/news/spectacular-flyover-of-mars-1.14041 | work = Nature News | access-date = November 17, 2013}}</ref>
*On 29 December, ''Mars Express'' performed the closest flyby to date of [[Phobos (moon)|Phobos]]
=== Second decade ===

==== 2014 ====
[[File:Rabe Crater perspective ESA310887.jpg|thumb|[[Rabe (crater)|Rabe crater]], 2014]]
* In October 2014, ESA reported ''Mars Express'' was healthy after the [[C/2013 A1|Comet Siding Spring]] flyby of Mars on 19 October<ref name="ESA-20141020">{{cite web |last=Denis |first=Michel |title=Spacecraft in great shape – our mission continues |url=http://blogs.esa.int/mex/2014/10/20/spacecraft-in-great-shape-our-mission-continues/ |date=October 20, 2014 |work=[[European Space Agency]] |access-date=October 21, 2014 }}</ref> &mdash; as were all NASA Mars orbiters<ref name="NASA-20141019">{{cite web |last1=Webster |first1=Guy |last2=Brown |first2=Dwayne |last3=Jones |first3=Nancy |last4=Steigerwald |first4=Bill |title=All Three NASA Mars Orbiters Healthy After Comet Flyby |url=http://www.jpl.nasa.gov/news/news.php?feature=4347 |date=October 19, 2014 |work=[[NASA]] |access-date=October 20, 2014 }}</ref> and [[Indian Space Research Organisation|ISRO's]] orbiter, the [[Mars Orbiter Mission]].<ref name="ISRO MOM safe after Mars comet flyby">{{cite news |author=Staff |title=I'm safe and sound, tweets MOM after comet sighting |url=http://www.thehindu.com/sci-tech/science/im-safe-and-sound-tweets-mom-after-comet-sighting/article6520803.ece |date=October 21, 2014 |work=[[The Hindu]] |access-date=October 21, 2014 }}</ref>

==== 2016 ====
* During a [[Phobos (moon)|Phobos]] flyby in January 2016, ''Mars Express'' again observed [[solar wind]] proton backscattering from the moon's surface. This was only second such observation by the spacecraft (first occured in 2008) and, as of 2025, this intermittency remains unexplained.<ref>{{Cite web |title=ESA’s Mars Express unravels mystery of martian moon using 'fake' flybys |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/ESA_s_Mars_Express_unravels_mystery_of_martian_moon_using_fake_flybys |access-date=2025-05-25 |website=www.esa.int |language=en}}</ref><ref>{{Cite journal |last=Futaana |first=Yoshifumi |last2=Holmström |first2=Mats |last3=Fedorov |first3=Andrey |last4=Barabash |first4=Stas |date=2021 |title=Does Phobos Reflect Solar Wind Protons? Mars Express Special Flyby Operations With and Without the Presence of Phobos |url=https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021JE006969 |journal=Journal of Geophysical Research: Planets |language=en |volume=126 |issue=11 |pages=e2021JE006969 |doi=10.1029/2021JE006969 |issn=2169-9100}}</ref>
* October 19: Assisted with data collection and transfer for the [[Schiaparelli EDM lander]] landing.
[[File:Martian south pole during summer by HRSC.jpg|thumb|South pole of Mars by ''Mars Express'', 2015 (ESA/DLR/FU Berlin)]]

==== 2017 ====
*On 19 June, the spacecraft took a notable image spanning from the North Pole up to [[Alba Mons]] and even farther south.<ref name="esamars">{{Cite web|url=http://www.sci-news.com/space/esa-image-mars-05553.html|title=ESA Releases Stunning New Image of Mars &#124; Space Exploration &#124; Sci-News.com|website=Breaking Science News &#124; Sci-News.com|date=December 20, 2017 }}</ref> The image was released in December 20, 2017, and was captured by HRSC.<ref name="esamars" /><ref>{{Cite web|url=https://www.dlr.de/EN/Service/about-relaunch/explanation.html?cms_url=https%3A%2F%2Fwww.dlr.de%2Fdlr%2Fen%2Fdesktopdefault.aspx%2Ftabid-10081%2F151_read-25327%2F|title=Relaunch explanation|website=NAV_NODE DLR Portal|access-date=October 19, 2019|archive-date=October 19, 2019|archive-url=https://web.archive.org/web/20191019051624/https://www.dlr.de/EN/Service/about-relaunch/explanation.html?cms_url=https%3A%2F%2Fwww.dlr.de%2Fdlr%2Fen%2Fdesktopdefault.aspx%2Ftabid-10081%2F151_read-25327%2F }}</ref>
[[File:Elongated cloud on Mars – annotated ESA401960.jpg|thumb|Elongated cloud on Mars, 2018<ref>{{Cite web |title=ESA Science & Technology - Elongated cloud on Mars &ndash; 10 October |url=https://sci.esa.int/web/mars-express/-/60882-elongated-cloud-on-mars-10-october |access-date=2025-05-20 |website=sci.esa.int}}</ref>]]

==== 2018 ====
[[File:Mars-SubglacialWater-SouthPoleRegion-20180725.jpg|thumb|Mars [[Planum Australe|South Pole]], site of [[Water on Mars|subglacial water]] (July 25, 2018)|354x354px]]
*Activated new AOCMS software which includes a gyroless attitude estimator to prolong the lifetime of the spacecraft's laser gyros<ref>{{Cite web |title=Mars Express v2.0 |url=https://www.esa.int/Enabling_Support/Operations/Mars_Express_v2.0 |access-date=April 12, 2022 |website=ESA.int }}</ref>
*In July 2018, a discovery was reported based on MARSIS [[radar]] studies, of a [[Water on Mars#Subglacial liquid water|subglacial lake]] on [[Mars]], {{convert|1.5|km|mi|abbr=on}} below the [[Planum Australe|southern polar ice cap]], and about {{convert|20|km|mi|abbr=on}} wide, the first known stable body of water on Mars.<ref name="SCI-20180725">{{cite journal |author=Orosei, R.|display-authors=etal|title=Radar evidence of subglacial liquid water on Mars |date=July 25, 2018 |journal=[[Science (journal)|Science]] |volume=361|issue=6401|pages=490–493|doi=10.1126/science.aar7268 |pmid=30045881|arxiv=2004.04587|hdl=11573/1148029|doi-access=free |bibcode=2018Sci...361..490O}}</ref><ref name="NYT-20180725">{{cite news |last1=Chang |first1=Kenneth |last2=Overbye |first2=Dennis |author-link2=Dennis Overbye |title=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. |url=https://www.nytimes.com/2018/07/25/science/mars-liquid-alien-life.html |date=July 25, 2018 |work=[[The New York Times]] |access-date=July 25, 2018 }}</ref><ref>{{cite web |title=Huge reservoir of liquid water detected under the surface of Mars |url=https://www.eurekalert.org/pub_releases/2018-07/aaft-hro072318.php |work=[[EurekAlert]]|date=July 25, 2018 |access-date=July 25, 2018 }}</ref><ref>{{cite web |title=Liquid water 'lake' revealed on Mars |url=https://www.bbc.co.uk/news/science-environment-44952710 |work=[[BBC News]]|date=July 25, 2018 |access-date=July 25, 2018 }}</ref>
* December 2018: ''Mars Express'' relays images of the 80-kilometer wide [[Korolev (Martian crater)|Korolev Crater]] filled with approximately 2200 cubic kilometers of water ice on the Martian surface.<ref name="DLR">{{cite web |title=A winter wonderland in red and white – Korolev Crater on Mars |url=https://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10081/151_read-31614/#/gallery/33106 |website=German Aerospace Center (DLR) |access-date=December 20, 2018}}</ref> Based on further evidence the crater ice is still part of much vaster ice resources at Mars poles.<ref name="TG1218">{{cite news |last=Sample |first=Ian |url=https://www.theguardian.com/science/2018/dec/21/mars-express-beams-back-images-of-ice-filled-korolev-crater |work=The Guardian |access-date=December 21, 2018 |title=Mars Express Beams Back Images of Ice-Filled Korolev Crater |date=December 21, 2018 }}</ref>

==== 2019 ====
*Based on data from the HRSC camera, there is geological evidence of an ancient planet-wide groundwater system.<ref>{{cite journal | doi = 10.1029/2018JE005802 | pmid = 31007995 | pmc = 6472477 | title = Geological Evidence of Planet-Wide Groundwater System on Mars | date = 2019 | last1 = Salese | first1 = Francesco | last2 = Pondrelli | first2 = Monica | last3 = Neeseman  | first3 = Alicia | last4 = Schmidt | first4 = Gene | last5 = Ori  | first5 = Gian Gabriele | journal = Journal of Geophysical Research: Planets | volume = 124 | issue = 2 | pages = 374–395 | bibcode = 2019JGRE..124..374S}}</ref><ref name="ESA">{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Mars_Express/First_evidence_of_planet-wide_groundwater_system_on_Mars|work=ESA|access-date=February 28, 2019|title=First evidence of planet-wide groundwater system on Mars}}</ref>

==== 2020 ====
*Between March and April 2020, ''Mars Express'' (along with other interplanetary missions by ESA) was briefly placed into a largely unattended safe configuration with science instruments turned off due to the worsening [[COVID-19 pandemic]] and the need to reduce on-site personnel at [[European Space Operations Centre|ESOC]].<ref>{{Cite web |title=ESA scales down science mission operations amid pandemic |url=https://www.esa.int/Science_Exploration/Space_Science/ESA_scales_down_science_mission_operations_amid_pandemic |access-date=2025-05-20 |website=www.esa.int |language=en}}</ref><ref>{{Cite web |title=Space missions return to science |url=https://www.esa.int/Enabling_Support/Operations/Space_missions_return_to_science |access-date=2025-05-20 |website=www.esa.int |language=en}}</ref>
*In September 2020, a discovery was reported based on MARSIS radar studies, of [[Water on Mars#Subglacial liquid water|three more subglacial lakes]] on Mars, {{convert|1.5|km|mi|abbr=on}} below the [[Planum Australe|southern polar ice cap]]. The size of the first lake found, and the largest, has been corrected to {{convert|30|km|mi|abbr=on}} wide. It is surrounded by 3 smaller lakes, each a few kilometres wide.<ref name="NatAstro">{{cite journal |last1=Lauro |first1=Sebastian Emanuel |last2=Pettinelli |first2=Elena |last3=Caprarelli |first3=Graziella |last4=Guallini |first4=Luca |last5=Rossi |first5=Angelo Pio |last6=Mattei |first6=Elisabetta |last7=Cosciotti |first7=Barbara |last8=Cicchetti |first8=Andrea |last9=Soldovieri |first9=Francesco |last10=Cartacci |first10=Marco |last11=Di Paolo |first11=Federico |last12=Noschese |first12=Raffaella |last13=Orosei |first13=Roberto |title=Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data |journal=Nature Astronomy |date=September 28, 2020 |volume=5 |pages=63–70 |doi=10.1038/s41550-020-1200-6 |publisher=Springer Nature Limited |arxiv=2010.00870 |s2cid=222125007 |issn=2397-3366}}</ref>
*A study published in December 2020 in [[JGR Planets|''JGR Planets'']] utilized the wide field of view of the [[Visual Monitoring Camera]], in combination with other instruments on ''Mars Express'' and other orbiters, to describe the life cycle of a large elongated [[orographic cloud]] that grows and fades on a daily basis during spring and summer over [[Arsia Mons]].<ref>{{Cite journal |last=Hernández-Bernal |first=J. |last2=Sánchez-Lavega |first2=A. |last3=del Río-Gaztelurrutia |first3=T. |last4=Ravanis |first4=E. |last5=Cardesín-Moinelo |first5=A. |last6=Connour |first6=K. |last7=Tirsch |first7=D. |last8=Ordóñez-Etxeberria |first8=I. |last9=Gondet |first9=B. |last10=Wood |first10=S. |last11=Titov |first11=D. |last12=Schneider |first12=N. M. |last13=Hueso |first13=R. |last14=Jaumann |first14=R. |last15=Hauber |first15=E. |date=2021 |title=An Extremely Elongated Cloud Over Arsia Mons Volcano on Mars: I. Life Cycle |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JE006517 |journal=Journal of Geophysical Research: Planets |language=en |volume=126 |issue=3 |pages=e2020JE006517 |doi=10.1029/2020JE006517 |issn=2169-9100}}</ref><ref>{{Cite web |title=Mars Express unlocks the secrets of curious cloud |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Mars_Express_unlocks_the_secrets_of_curious_cloud |access-date=2025-05-21 |website=www.esa.int |language=en}}</ref> A follow-up study published in 2022 used [[computational modeling]] to describe the physical mechanisms behind the cloud's formation.<ref>{{Cite journal |last=Hernández-Bernal |first=J. |last2=Spiga |first2=A. |last3=Sánchez-Lavega |first3=A. |last4=del Río-Gaztelurrutia |first4=T. |last5=Forget |first5=F. |last6=Millour |first6=E. |date=2022 |title=An Extremely Elongated Cloud Over Arsia Mons Volcano on Mars: 2. Mesoscale Modeling |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022JE007352 |journal=Journal of Geophysical Research: Planets |language=en |volume=127 |issue=10 |pages=e2022JE007352 |doi=10.1029/2022JE007352 |issn=2169-9100}}</ref>

==== 2021 ====
* Two studies published in December 2020<ref>{{Cite journal |last=Fedorova |first=Anna |last2=Montmessin |first2=Franck |last3=Korablev |first3=Oleg |last4=Lefèvre |first4=Franck |last5=Trokhimovskiy |first5=Alexander |last6=Bertaux |first6=Jean-Loup |date=2021 |title=Multi-Annual Monitoring of the Water Vapor Vertical Distribution on Mars by SPICAM on Mars Express |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JE006616 |journal=Journal of Geophysical Research: Planets |language=en |volume=126 |issue=1 |pages=e2020JE006616 |doi=10.1029/2020JE006616 |issn=2169-9100}}</ref> and January 2021,<ref>{{Cite journal |last=Chaufray |first=J. -Y. |last2=Gonzalez-Galindo |first2=F. |last3=Lopez-Valverde |first3=M. A. |last4=Forget |first4=F. |last5=Quémerais |first5=E. |last6=Bertaux |first6=J. -L. |last7=Montmessin |first7=F. |last8=Chaffin |first8=M. |last9=Schneider |first9=N. |last10=Clarke |first10=J. T. |last11=Leblanc |first11=F. |last12=Modolo |first12=R. |last13=Yelle |first13=R. V. |date=2021-01-01 |title=Study of the hydrogen escape rate at Mars during martian years 28 and 29 from comparisons between SPICAM/Mars express observations and GCM-LMD simulations |url=https://www.sciencedirect.com/science/article/abs/pii/S0019103518306985 |journal=Icarus |series=From Mars Express to Exomars |volume=353 |pages=113498 |doi=10.1016/j.icarus.2019.113498 |issn=0019-1035}}</ref> that analyzed SPICAM data, show that water escape to space is accelerated by dust storms and Mars' proximity to the Sun, and suggest that some water may have retreated underground.<ref>{{Cite web |title=Mars water loss shaped by seasons and storms |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Mars_water_loss_shaped_by_seasons_and_storms |access-date=2025-05-22 |website=www.esa.int |language=en}}</ref>
* A study published in April 2021, that used SPICAM data to analyze the relationship between ozone and water vapour in the atmosphere of Mars, identified a previously unknown problem with climate models, that might be relevant also to studying the Earth's atmosphere.<ref>{{Cite web |title=Better understanding of Earth’s atmospheric chemistry from studying Mars? |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Better_understanding_of_Earth_s_atmospheric_chemistry_from_studying_Mars |access-date=2025-05-24 |website=www.esa.int |language=en}}</ref><ref>{{Cite journal |last=Lefèvre |first=F. |last2=Trokhimovskiy |first2=A. |last3=Fedorova |first3=A. |last4=Baggio |first4=L. |last5=Lacombe |first5=G. |last6=Määttänen |first6=A. |last7=Bertaux |first7=J.-L. |last8=Forget |first8=F. |last9=Millour |first9=E. |last10=Venot |first10=O. |last11=Bénilan |first11=Y. |last12=Korablev |first12=O. |last13=Montmessin |first13=F. |date=2021 |title=Relationship Between the Ozone and Water Vapor Columns on Mars as Observed by SPICAM and Calculated by a Global Climate Model |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JE006838 |journal=Journal of Geophysical Research: Planets |language=en |volume=126 |issue=4 |pages=e2021JE006838 |doi=10.1029/2021JE006838 |issn=2169-9100}}</ref>
* In November 2021, an experiment was performed to test whether ''Mars Express'' and the [[Trace Gas Orbiter|TGO]] lander relay communications radio could be used to perform [[radio occultation]] science,<ref>{{Cite web |title=ESA Mars orbiters: two-for-one science – Mars Express |url=https://blogs.esa.int/mex/2021/11/17/esa-mars-orbiters-two-for-one-science/ |access-date=April 11, 2022 }}</ref> as well as a series of tests of data relay from the CNSA [[Zhurong rover|''Zhurong'' rover]].<ref>{{Cite web |title=Mars Express keeps an ear out for Chinese rover – Mars Express |url=https://blogs.esa.int/mex/2021/10/27/mars-express-keeps-an-ear-out-for-chinese-rover/ |access-date=April 11, 2022 }}</ref>

==== 2022 ====
* On 14 February 2022, ''Mars Express'' observed a rare astronomical event — [[Deimos (moon)|Deimos]] passing in front of Jupiter and its [[Galilean moons]]. Measuring the duration of the occultation enabled a more precise determination of the position and orbit of Deimos.<ref>{{Cite web |last= |first= |date=2022 |title=Mars Express Observes Rare Celestial Alignments in Solar System {{!}} Sci.News |url=https://www.sci.news/space/mars-express-alignments-11295.html |access-date=2025-06-01 |website=Sci.News: Breaking Science News |language=en-US}}</ref>
* The onboard software of the MARSIS experiment was upgraded from [[Windows 98]] to Mars 2022 in order to improve the performance of the instrument.<ref>{{Cite web |title=Software Upgrade for 19-Year-Old Martian Water-Spotter |url=https://www.esa.int/Enabling_Support/Operations/Software_upgrade_for_19-year-old_martian_water-spotter |access-date=July 2, 2022 }}</ref><ref>{{Cite web |title=This Mars Orbiter Is Finally Getting A Software Update From Windows 98 |date=June 29, 2022 |url=https://www.slashgear.com/912406/this-mars-orbiter-is-finally-getting-a-software-update-from-windows-98/ |access-date=July 2, 2022 }}</ref>

==== 2023 ====
* In January 2023, the first global high-resolution map of aqueous minerals (formed through interaction with water) at Mars was published using data from ''Mars Exp''<nowiki/>''ress''<nowiki/>' OMEGA and [[Mars Reconnaissance Orbiter|MRO]]'s CRISM instruments.<ref>{{Cite web |title=New water map of Mars will prove invaluable for future exploration |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/New_water_map_of_Mars_will_prove_invaluable_for_future_exploration |access-date=2025-05-18 |website=www.esa.int |language=en}}</ref><ref>{{Cite journal |last1=Carter |first1=John |last2=Riu |first2=Lucie |last3=Poulet |first3=François |last4=Bibring |first4=Jean-Pierre |last5=Langevin |first5=Yves |last6=Gondet |first6=Brigitte |date=2023 |title=A Mars orbital catalog of aqueous alteration signatures (MOCAAS) |url=https://linkinghub.elsevier.com/retrieve/pii/S0019103522002664 |journal=Icarus |language=en |volume=389 |pages=115164 |doi=10.1016/j.icarus.2022.115164|bibcode=2023Icar..38915164C }}</ref>
* June 3: 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.<ref>{{Cite web |title=Tune in for first Mars livestream |url=https://www.esa.int/Enabling_Support/Operations/Tune_in_for_first_Mars_livestream |access-date=June 2, 2023 }}</ref>

=== Third decade ===
[[File:Olympus Mons - ESA Mars Express.png|thumb|[[Olympus Mons]] - ESA ''Mars Express'' [[High Resolution Stereo Camera|HRSC instrument]] image]]

==== 2024 ====
* Published in January 2024, a new research analysed [[MARSIS]] radar data collected over the preceding decade and concluded that the [[Medusae Fossae Formation]] at Mars equator, previously thought to be likely composed of dry deposits, instead includes a large amount of water ice.<ref>{{Cite web |title=Buried water ice at Mars's equator? |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Buried_water_ice_at_Mars_s_equator |access-date=2025-05-18 |website=www.esa.int |language=en}}</ref><ref>{{Cite journal |last1=Watters |first1=Thomas R. |last2=Campbell |first2=Bruce A. |last3=Leuschen |first3=Carl J. |last4=Morgan |first4=Gareth A. |last5=Cicchetti |first5=Andrea |last6=Orosei |first6=Roberto |last7=Plaut |first7=Jeffrey J. |date=2024 |title=Evidence of Ice-Rich Layered Deposits in the Medusae Fossae Formation of Mars |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GL105490 |journal=Geophysical Research Letters |language=en |volume=51 |issue=2 |pages=e2023GL105490 |doi=10.1029/2023GL105490 |bibcode=2024GeoRL..5105490W |issn=1944-8007}}</ref>

* In May 2024, computers on ''Mars Express'' (as well as on another ESA mission, ''[[BepiColombo]]'') reported a sharp increase in the number of memory errors, coinciding with a massive [[solar flare]].<ref>{{Cite web |title=Can't stop won't stop: Solar Orbiter shows the Sun raging on |url=https://www.esa.int/Science_Exploration/Space_Science/Solar_Orbiter/Can_t_stop_won_t_stop_Solar_Orbiter_shows_the_Sun_raging_on |access-date=2025-05-18 |website=www.esa.int |language=en}}</ref>
* In June 2024, a new study was published in [[Nature Geoscience|''Nature Geoscience'']], providing first evidence for water frost near Mars equator, specificaly atop the [[Tharsis]] volcanoes. This work used data from ESA's ''Mars Express'' and [[Trace Gas Orbiter|TGO]] missions.<ref>{{Cite web |date=2024-07-01 |title=Surprising Discovery of Frost on Martian Volcanoes Near Equator – "Thought Impossible" |url=https://scitechdaily.com/surprising-discovery-of-frost-on-martian-volcanoes-near-equator-thought-impossible/ |access-date=2025-05-18 |website=SciTechDaily |language=en-US}}</ref><ref>{{Cite journal |last1=Valantinas |first1=A. |last2=Thomas |first2=N. |last3=Pommerol |first3=A. |last4=Karatekin |first4=O. |last5=Ruiz Lozano |first5=L. |last6=Senel |first6=C. B. |last7=Temel |first7=O. |last8=Hauber |first8=E. |last9=Tirsch |first9=D. |last10=Bickel |first10=V. T. |last11=Munaretto |first11=G. |last12=Pajola |first12=M. |last13=Oliva |first13=F. |last14=Schmidt |first14=F. |last15=Thomas |first15=I. |date=2024 |title=Evidence for transient morning water frost deposits on the Tharsis volcanoes of Mars |url=https://www.nature.com/articles/s41561-024-01457-7 |journal=Nature Geoscience |language=en |volume=17 |issue=7 |pages=608–616 |doi=10.1038/s41561-024-01457-7 |bibcode=2024NatGe..17..608V |issn=1752-0908}}</ref>
* In July 2024, a study was published in [[Radio Science|''Radio Science'']] documenting the first routine use of mutual radio occultation technique at another planet, specifically the measurements of physical properties of the [[Atmosphere of Mars|Martian atmosphere]] conducted using a radio link between ESA's ''Mars Express'' and [[Trace Gas Orbiter|TGO]] orbiters between 2020 and 2023.<ref>{{Cite web |last1=Dunning |first1=Hayley |last2=London |first2=Imperial College |title=Repurposed technology used to probe new regions of Mars' atmosphere |url=https://phys.org/news/2024-07-repurposed-technology-probe-regions-mars.html |access-date=2025-05-18 |website=phys.org |language=en}}</ref><ref>{{Cite journal |last1=Parrott |first1=Jacob |last2=Svedhem |first2=Håkan |last3=Witasse |first3=Olivier |last4=Wilson |first4=Colin |last5=Müller-Wodarg |first5=Ingo |last6=Cardesín-Moinelo |first6=Alejandro |last7=Schmitz |first7=Peter |last8=Godfrey |first8=James |last9=Reboud |first9=Olivier |last10=Geiger |first10=Bernhard |last11=Sánchez-Cano |first11=Beatriz |last12=Nava |first12=Bruno |last13=Migoya-Orué |first13=Yenca |date=2024 |title=First Results of Mars Express—ExoMars Trace Gas Orbiter Mutual Radio Occultation |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023RS007873 |journal=Radio Science |language=en |volume=59 |issue=7 |pages=e2023RS007873 |doi=10.1029/2023RS007873 |bibcode=2024RaSc...5907873P |issn=1944-799X}}</ref>

* In September 2024, a new cloud atlas of Mars has been published, containing images of Martian clouds by ''Mars Express'' from the past 20 years.<ref>{{Cite web |last=Anderson |first=Paul Scott |date=2024-09-18 |title=New Cloud Atlas of Mars for cloudspotting on the red planet |url=https://earthsky.org/space/cloud-atlas-of-mars-clouds-dust-storms/ |access-date=2025-05-18 |website=earthsky.org |language=en-US}}</ref><ref>{{Cite report |url=https://meetingorganizer.copernicus.org/EPSC2024/EPSC2024-44.html |title=Clouds and Storms as seen by HRSC - A catalogue of atmospheric phenomena on Mars |last1=Tirsch |first1=Daniela |last2=Machado |first2=Pedro |last3=Brasil |first3=Francisco |last4=Hernández-Bernal |first4=Jorge |last5=Sánchez-Lavega |first5=Agustín |last6=Carter |first6=John |last7=Montmessin |first7=Franck |last8=Hauber |first8=Ernst |last9=Matz |first9=Klaus-Dieter |date=2024-07-03 |publisher=Copernicus Meetings |issue=EPSC2024-44 |doi=10.5194/epsc2024-44 |doi-access=free |language=en}}</ref>

==== 2025 ====
* In February 2025, a study was published in ''[[Nature Communications]]'' suggesting that the red color of Mars is caused by iron oxides containing water, known as [[ferrihydrite]], and not by [[hematite]] that forms under dry conditions, as thought before. This work used data from ''Mars Express'' and other spacecraft.<ref>{{Cite web |title=Have we been wrong about why Mars is red? |url=https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Have_we_been_wrong_about_why_Mars_is_red |access-date=2025-05-18 |website=www.esa.int |language=en}}</ref><ref>{{Cite journal |last1=Valantinas |first1=Adomas |last2=Mustard |first2=John F. |last3=Chevrier |first3=Vincent |last4=Mangold |first4=Nicolas |last5=Bishop |first5=Janice L. |last6=Pommerol |first6=Antoine |last7=Beck |first7=Pierre |last8=Poch |first8=Olivier |last9=Applin |first9=Daniel M. |last10=Cloutis |first10=Edward A. |last11=Hiroi |first11=Takahiro |last12=Robertson |first12=Kevin |last13=Pérez-López |first13=Sebastian |last14=Ottersberg |first14=Rafael |last15=Villanueva |first15=Geronimo L. |date=2025-02-25 |title=Detection of ferrihydrite in Martian red dust records ancient cold and wet conditions on Mars |journal=Nature Communications |language=en |volume=16 |issue=1 |pages=1712 |doi=10.1038/s41467-025-56970-z |pmid=40000645 |pmc=11861699 |bibcode=2025NatCo..16.1712V |issn=2041-1723}}</ref>
* In May 2025, ESA updated the software solution from 2018 which was meant to prolong the lifetime of the spacecraft's gyroscopes. This new update could allow ''Mars Express'' to stay operational until 2034 and be ready to support the [[Martian Moons eXploration|MMX spacecraft]] in 2029.<ref>{{Cite web |title=Mars Express updates software, extends lifetime until 2034 |url=https://www.esa.int/Enabling_Support/Operations/Mars_Express_updates_software_extends_lifetime_until_2034 |access-date=2025-05-17 |website=www.esa.int |language=en}}</ref>