Editing Deimos (moon) (section)

== Exploration ==
[[File:PIA17351-ApparentSizes-MarsDeimosPhobos-EarthMoon.jpg|thumb|Deimos and Phobos as seen from Mars, compared to the [[Moon]] as seen from Earth (in [[angular size]]s)]]
Overall, its exploration history is similar to those [[exploration of Mars|of Mars]] and [[Phobos (moon)#Exploration|of Phobos]].<ref>[http://oro.open.ac.uk/10715/1/Mars_Phobos_and_Deimos_Survey_revised2.pdf Mars Phobos and Deimos Survey (M-PADS)–A Martian Moons Orbiter and Phobos Lander] (Ball, Andrew J.; Price, Michael E.; Walker, Roger J.; Dando, Glyn C.; Wells, Nigel S; and Zarnecki, John C. (2009). Mars Phobos and Deimos Survey (M-PADS)–A Martian Moons Orbiter and Phobos Lander. Advances in Space Research, 43(1), pp. 120–127.)</ref> Deimos has been photographed close-up by several spacecraft whose primary mission has been to photograph Mars, including in March 2023 during a rare close encounter by the [[Emirates Mars Mission]].<ref>{{cite web |last1=Crane |first1=Leah |title=Amazing images of Mars's moon Deimos snapped by Emirates Mars Mission |url=https://www.newscientist.com/article/2370417-amazing-images-of-marss-moon-deimos-snapped-by-emirates-mars-mission/ |website=New Scientist |access-date=25 April 2023}}</ref> No landings on Deimos have been made.

In 1997 and 1998, the proposed ''Aladdin'' mission was selected as a finalist in the NASA [[Discovery Program]]. The plan was to visit both Phobos and Deimos, and launch projectiles at the satellites. The probe would collect the ejecta as it performed a slow flyby (~1&nbsp;km/s).<ref>{{cite book|last=Barnouin-Jha|first=Olivier S.|chapter=Aladdin: sample return from the moons of Mars|doi=10.1109/AERO.1999.794346|title=1999 IEEE Aerospace Conference. Proceedings (Cat. No.99TH8403)|volume=1|pages=403–412 vol.1|year=1999|isbn=978-0-7803-5425-8|s2cid=129101577}}</ref> These samples would be returned to Earth for study three years later.<ref>{{cite web|last=Pieters|first=Carle|title=ALADDIN: PHOBOS–DEIMOS SAMPLE RETURN|url=http://www.lpi.usra.edu/meetings/lpsc97/pdf/1113.PDF|work=28th Annual Lunar and Planetary Science Conference|access-date=28 March 2013}}</ref><ref>{{cite web|title=Messenger and Aladdin Missions Selected as NASA Discovery Program Candidates|url=http://www.jhuapl.edu/newscenter/pressreleases/1998/managed.asp|access-date=28 March 2013|archive-date=4 April 2017|archive-url=https://web.archive.org/web/20170404212543/http://www.jhuapl.edu/newscenter/pressreleases/1998/managed.asp|url-status=dead}}</ref> The principal investigator was [[Carle M. Pieters]] of [[Brown University]]. The total mission cost, including launch vehicle and operations was $247.7 million.<ref>{{cite web|title=Five Discovery mission proposals selected for feasibility studies|url=http://nssdc.gsfc.nasa.gov/planetary/text/discovery_pr_19981112.txt|access-date=28 March 2013}}</ref> Ultimately, the mission chosen to fly was ''[[MESSENGER]]'', a probe to the planet [[Mercury (planet)|Mercury]].<ref>{{cite web|title=NASA Selects Missions to Mercury and a Comet's Interior as Next Discovery Flights|url=http://nssdc.gsfc.nasa.gov/planetary/news/discovery_pr_19990707.html|access-date=28 March 2013}}</ref>

In 2008, NASA [[Glenn Research Center]] began studying a Phobos and Deimos [[sample-return mission]] that would use solar electric propulsion. The study gave rise to the "Hall" mission concept, a [[New Frontiers program|New Frontiers]]-class mission currently under further study.<ref>Lee, P. et al. 2010. Hall: A Phobos and Deimos Sample Return Mission. ''44th Lunar Planet. Sci. Conf.'', The Woodlands, TX. 1–5 Mar 2010. [#1633] {{bibcode|2010LPI....41.1633L}}.</ref>

Also, the sample-return mission called ''Gulliver'' has been conceptualized and dedicated to Deimos,<ref name=britt>{{Cite web|url=http://meetings.copernicus.org/epsc2010/abstracts/EPSC2010-463.pdf|title=Dr. Britt – The Gulliver Mission: Sample Return from Deimos}}</ref> in which 1 kilogram (2.2 pounds) of material from Deimos would be returned to Earth.<ref name="britt" />

Another concept of sample-return mission from Phobos and Deimos is ''OSIRIS-REx&nbsp;2'', which would use heritage from the first ''[[OSIRIS-REx]]''.<ref>{{Cite journal|url=https://ui.adsabs.harvard.edu/abs/2012LPICo1679.4017E|title=OSIRIS-REx II to Mars — Mars Sample Return from Phobos and Deimos|first=T. L.|last=Elifritz|journal=Concepts and Approaches for Mars Exploration |date=1 June 2012|volume=1679|pages=4017|bibcode=2012LPICo1679.4017E |via=NASA ADS}}</ref>

In March 2014, a Discovery class mission was proposed to place an orbiter in Mars orbit by 2021 and study Phobos and Deimos. It was called ''[[Phobos And Deimos & Mars Environment]]'' (PADME).<ref name="lpsc 2014">{{cite conference |last1=Lee |first1=Pascal |last2=Bicay |first2=Michael |last3=Colapre |first3=Anthony |last4=Elphic |first4=Richard |title=Phobos And Deimos & Mars Environment (PADME): A LADEE-Derived Mission to Explore Mars's Moons and the Martian Orbital Environment. |url=http://www.hou.usra.edu/meetings/lpsc2014/pdf/2288.pdf |conference=45th Lunar and Planetary Science Conference (2014) |conference-url=http://www.hou.usra.edu/meetings/lpsc2014/ |date= 17–21 March 2014}}</ref><ref name="Reyes 2014">{{cite news |last=Reyes |first=Tim |url=http://www.universetoday.com/114871/making-the-case-for-a-mission-to-the-martian-moon-phobos/ |title=Making the Case for a Mission to the Martian Moon Phobos |work=Universe Today |date=1 October 2014 |access-date=5 October 2014}}</ref>

Human exploration of Deimos could serve as a catalyst for the human exploration of Mars. Recently,  it was proposed that the sands of Deimos or Phobos could serve as a valuable material for [[aerobraking]] in the colonization of Mars.<ref name="arias16">{{Cite conference |last=Arias |first=Francisco. J |date=2017 |title=On the Use of the Sands of Phobos and Deimos as a Braking Technique for Landing Large Payloads on Mars |conference=53rd AIAA/SAE/ASEE Joint Propulsion Conference |location=Atlanta, GA |doi=10.2514/6.2017-4876 |isbn=978-1-62410-511-1 |id=AIAA 201–4876}}</ref> See [[Phobos (moon)#Human missions|Phobos]] for more detail.

[[Indian Space Research Organisation|ISRO]]'s [[Mars Orbiter Mission]] captured the first pictures of the far side on Deimos.{{citation needed|date=August 2024}}

In April 2023, astronomers released close-up global images, for the first time, of Deimos that were taken by the Mars [[Hope orbiter]].<ref>{{Cite journal |last=Castelvecchi |first=Davide |date=24 April 2023 |title=First up-close images of Mars's little-known moon Deimos |url=https://www.nature.com/articles/d41586-023-01422-1 |journal=Nature |volume=617 |issue=7959 |pages=19 |bibcode=2023Natur.617...19C |doi=10.1038/d41586-023-01422-1 |pmid=37095410 |s2cid=258311112 |archive-url=https://web.archive.org/web/20230501165918/https://www.nature.com/articles/d41586-023-01422-1 |url-status=live|archive-date=1 May 2023 |access-date=5 May 2023}}</ref><ref name="SPC-20230424">{{cite news |last=Howell |first=Elizabeth |title=This is our 1st detailed look at Mars's most mysterious moon Deimos (photos) - The debate over the moon's origin story is not over yet. |url=https://www.space.com/mars-moon-deimos-image-origin-story |date=24 April 2023 |work=[[Space.com]] |accessdate=25 April 2023 }}</ref> Observations reported by this mission contravene the captured asteroid hypothesis and indicate [[basalt]]ic planetary origin of Deimos.<ref>{{cite news |url=https://www.sharjah24.ae/en/Articles/2023/04/24/EMM-unveils-new-Deimos-observations-at-EGU23-extends-mission |title=EMM unveils new Deimos observations at EGU23, extends mission |date=24 April 2023 |newspaper=Sharjah24}}</ref>

During its [[gravity assist]] from Mars en route to [[65803 Didymos]], the [[European Space Agency|ESA]]'s [[Hera (space mission)|''Hera'']] took observations of Deimos in March 2025, approaching at a distance of 300 km (190 mi).<ref>{{Cite web |last=Agency |first=European Space |title=Video: Time lapse simulation of Hera's Mars flyby |url=https://phys.org/news/2025-03-video-lapse-simulation-hera-mars.html |access-date=2025-03-13 |website=phys.org |language=en}}</ref>

The JAXA [[Martian Moons eXploration|MMX]] Mission [[Phobos (moon)#Exploration|to Phobos]] and Deimos is planned for launch in October 2026.<ref>{{cite web|title= JAXA Martian Moons eXploration mission |url=https://www.mmx.jaxa.jp/en/ |access-date=24 January 2025}}</ref> It will make flybys of Deimos to investigate its composition and structure, as well as performing a sample return [[Phobos (moon)#Exploration|on Phobos]] and placing a rover on that moon.