Sample-return mission

File:Apollo 15 Genesis Rock.jpg, returned by the Apollo 15 lunar mission in 1971.]]

File:OSIRIS-REx Sample Return (NHQ202309240003).jpg mission shortly after touching down in the desert in Utah]]

A sample-return mission is a spacecraft mission to collect and return samples from an extraterrestrial location to Earth for analysis. Sample-return missions may bring back merely atoms and molecules or a deposit of complex compounds such as loose material and rocks. These samples may be obtained in a number of ways, such as soil and rock excavation or a collector array used for capturing particles of solar wind or cometary debris. Nonetheless, concerns have been raised that the return of such samples to planet Earth may endanger Earth itself.{{cite news |last=David |first=Leonard |title=Controversy Grows Over whether Mars Samples Endanger Earth - Planetary scientists are eager to bring Red Planet rocks, soil and even air to Earth, but critics fear the risk of contaminating our world's biosphere |url=https://www.scientificamerican.com/article/controversy-grows-over-whether-mars-samples-endanger-earth/ |date=23 June 2022 |work=Scientific American |accessdate=5 July 2022 }}

To date, samples of Moon rock from Earth's Moon have been collected by robotic and crewed missions; the comet Wild 2 and the asteroids 25143 Itokawa, 162173 Ryugu, and 101955 Bennu have been visited by robotic spacecraft which returned samples to Earth; and samples of the solar wind have been returned by the robotic Genesis mission.

In addition to sample-return missions, samples from three identified non-terrestrial bodies have been collected by other means: samples from the Moon in the form of Lunar meteorites, samples from Mars in the form of Martian meteorites, and samples from Vesta in the form of HED meteorites.

Scientific use

File:MarsMeteorite-NWA7034-716969main black beauty full.jpg

Samples available on Earth can be analyzed in laboratories, so we can further our understanding and knowledge as part of the discovery and exploration of the Solar System. Until now, many important scientific discoveries about the Solar System were made remotely with telescopes, and some Solar System bodies were visited by orbiting or even landing spacecraft with instruments capable of remote sensing or sample analysis. While such an investigation of the Solar System is technically easier than a sample-return mission, the scientific tools available on Earth to study such samples are far more advanced and diverse than those that can go on spacecraft. Further, analysis of samples on Earth allows follow up of any findings with different tools, including tools that can tell intrinsic extraterrestrial material from terrestrial contamination,{{cite journal |last1=Chan |first1=Queenie Hoi Shan |last2=Stroud |first2=Rhonda|author2-link= Rhonda Stroud |last3=Martins |first3=Zita |last4=Yabuta |first4=Hikaru |title=Concerns of Organic Contamination for Sample Return Space Missions |journal=Space Science Reviews |date=12 May 2020 |volume=216 |issue=4 |page=56 |doi=10.1007/s11214-020-00678-7 |pmid=32624626 |pmc=7319412 |bibcode=2020SSRv..216...56C |doi-access=free }} and those that have yet to be developed; in contrast, a spacecraft can carry only a limited set of analytic tools, and these have to be chosen and built long before launch.

Samples analyzed on Earth can be matched against findings of remote sensing for more insight into the processes that formed the Solar System. This was done, for example, with findings by the Dawn spacecraft, which visited the asteroid Vesta from 2011 to 2012 for imaging, and samples from HED meteorites (collected on Earth until then), which were compared to data gathered by Dawn.[http://www.planetary.org/blogs/emily-lakdawalla/2014/10091306-what-did-dawn-learn-at-vesta.html What did Dawn learn at Vesta?] The Planetary Society. These meteorites could then be identified as material ejected from the large impact crater Rheasilvia on Vesta. This allowed deducing the composition of the crust, mantle and core of Vesta. Similarly, some differences in the composition of asteroids (and, to a lesser extent, different compositions of comets) can be discerned by imaging alone. However, for a more precise inventory of the material on these different bodies, more samples will be collected and returned in the future, to match their compositions with the data gathered through telescopes and astronomical spectroscopy.

One further focus of such investigation—besides the basic composition and geologic history of the various Solar System bodies—is the presence of the building blocks of life on comets, asteroids, Mars or the moons of the gas giants. Several sample-return missions to asteroids and comets are currently in the works. More samples from asteroids and comets will help determine whether life formed in space and was carried to Earth by meteorites. Another question under investigation is whether extraterrestrial life formed on other Solar System bodies like Mars or on the moons of the gas giants, and whether life might even exist there. The result of NASA's last "Decadal Survey" was to prioritize a Mars sample-return mission, as Mars has a special importance: it is comparatively "nearby", might have harbored life in the past, and might even continue to sustain life. Jupiter's moon Europa is another important focus in the search for life in the Solar System. However, due to the distance and other constraints, Europa might not be the target of a sample-return mission in the foreseeable future.

Planetary protection

{{Further|Planetary protection|Extraterrestrial sample curation}}

Planetary protection aims to prevent biological contamination of both the target celestial body and the Earth in the case of sample-return missions. A sample return from Mars or other location with the potential to host life is a category V mission under COSPAR, which directs to the containment of any unsterilized sample returned to Earth. This is because it is unknown what the effects such hypothetical life would be on humans or the biosphere of Earth.Joshua Lederberg [http://profiles.nlm.nih.gov/ps/access/BBGNMX.pdf Parasites Face a Perpetual Dilemma] (PDF). Volume 65, Number 2, 1999 / American Society for Microbiology News 77. For this reason, Carl Sagan and Joshua Lederberg argued in the 1970s that we should do sample-return missions classified as category V missions with extreme caution, and later studies by the NRC and ESF agreed.{{cite report |title=Assessment of Planetary Protection Requirements for Mars Sample Return Missions |publisher=National Research Council |date=2009 |url=http://www.nap.edu/openbook.php?record_id=12576&page=R1}}[https://web.archive.org/web/20130124081409/http://mepag.nasa.gov/reports/iMARS_FinalReport.pdf Preliminary Planning for an International Mars Sample Return Mission Report] of the International Mars Architecture for the Return of Samples (iMARS) Working Group 1 June 2008.[https://science.nasa.gov/media/medialibrary/2013/01/17/ESF_Mars_Sample_Return_backward_contamination_study.pdf European Science Foundation – Mars Sample Return backward contamination – Strategic advice and requirements] {{webarchive|url=https://web.archive.org/web/20160602150139/http://science.nasa.gov/media/medialibrary/2013/01/17/ESF_Mars_Sample_Return_backward_contamination_study.pdf |date=2016-06-02 }} July, 2012, {{ISBN|978-2-918428-67-1}} – see Back Planetary Protection section. (for more details of the document see [http://elib.dlr.de/78092/ abstract]).[http://planetaryprotection.nasa.gov/summary/msr Mars Sample Return: Issues and Recommendations]. Task Group on Issues in Sample Return. National Academies Press, Washington, DC (1997).

Sample-return missions

=First missions=

File:Apollo 11 2004 scan.jpg was the first mission to return extraterrestrial samples.]]

File:NASA Lunar Sample 60016.jpg

In July 1969, Apollo 11 achieved the first successful sample return from another Solar System body when it returned {{convert|22|kg}} of Lunar surface material. This was followed by {{convert|34|kg}} of material and Surveyor 3 parts from Apollo 12, {{convert|42.8|kg}} of material from Apollo 14, {{convert|76.7|kg}} of material from Apollo 15, {{convert|94.3|kg}} of material from Apollo 16, and {{convert|110.4|kg}} of material from Apollo 17.{{Citation needed|date=March 2019}} The Apollo program as a whole returned over {{convert|382|kg|lb|abbr=on}} of lunar rocks and regolith, including lunar soil, to the Lunar Receiving Laboratory in Houston.{{cite web |date=1 September 2016 |title=NASA Lunar Sample Laboatory Facility |url=https://curator.jsc.nasa.gov/lunar/lun-fac.cfm |access-date=15 February 2017 |website=NASA Curation Lunar |publisher=NASA |quote=A total of 382 kilograms of lunar material, comprising 2200 individual specimens returned from the Moon...}}Orloff 2004, [https://history.nasa.gov/SP-4029/Apollo_18-30_Extravehicular_Activity.htm "Extravehicular Activity"]{{cite book |last1=Chaikin |first1=Andrew |title=A Man On the Moon: The Voyages of the Apollo Astronauts |publisher=Penguin Books |year=2007 |edition=Third |location=New York |pages=611–613}} Today, 75% of the samples are stored at the Lunar Sample Laboratory Facility built in 1979.{{cite web |author=Kristen Erickson |date=16 July 2009 |editor=Amiko Kauderer |title=Rock Solid: JSC's Lunar Sample Lab Turns 30 |url=http://www.nasa.gov/mission_pages/apollo/40th/jsc_lunar_sample_lab_30.html |access-date=29 June 2012 |work=40th Anniversary of Apollo Program |publisher=NASA}}

In 1970, the robotic Soviet mission Luna 16 returned {{convert|101|g}} of lunar soil, followed by Luna 20's return of {{convert|55|g}} in 1974, and Luna 24's return of {{convert|170|g}} in 1976. Although they recovered far less than the Apollo missions, they did this fully automatically. Apart from these three successes, other attempts under the Luna programme failed. The first two missions were intended to compete with Apollo 11 and were undertaken shortly before it in June and July 1969. Luna E-8-5 No. 402 failed at start, and Luna 15 crashed on the Moon. Later, other sample-return missions failed: Kosmos 300 and Kosmos 305 in 1969, Luna E-8-5 No. 405 in 1970, Luna E-8-5M No. 412 in 1975 had unsuccessful launches, and Luna 18 in 1971 and Luna 23 in 1974 had unsuccessful landings on the Moon.{{cite web|url=http://www.astronautix.com/craft/lunaye85.htm|archive-url=https://web.archive.org/web/20020225145318/http://www.astronautix.com/craft/lunaye85.htm|url-status=dead|archive-date=25 February 2002|title=Luna Ye-8-5|last=Wade|first=Mark|publisher=Encyclopedia Astronautica|access-date=27 July 2010}}

In 1970, the Soviet Union planned for a 1975 first Mars sample-return mission in the Mars 5NM project. This mission was planned to use an N1 rocket, but this rocket never flew successfully and the mission evolved into the Mars 5M project, which would use a double launch with the smaller Proton rocket and an assembly at a Salyut space station. This Mars 5M mission was planned for 1979, but was canceled in 1977 due to technical problems and complexity.[http://www.novosti-kosmonavtiki.ru/content/numbers/213/50.shtml Советский грунт с Марса] {{in lang|ru}} {{webarchive |url=https://web.archive.org/web/20100408175307/http://www.novosti-kosmonavtiki.ru/content/numbers/213/50.shtml |date=8 April 2010 }}

=1990s=

The Orbital Debris Collection (ODC) experiment deployed on the Mir space station for 18 months in 1996–97 used aerogel to capture particles from low Earth orbit, including both interplanetary dust and man-made particles.{{cite web |title=Orbital Debris Collector (ODC) |url=https://historycollection.jsc.nasa.gov/history/shuttle-mir/science/iss/sc-iss-odc.htm |archive-url=https://web.archive.org/web/20210521230455/https://historycollection.jsc.nasa.gov/history/shuttle-mir/science/iss/sc-iss-odc.htm |url-status=dead |archive-date=21 May 2021 |website=NASA |access-date=7 April 2021 |date=16 July 1999}}

=2000s=

File:GenSC collection2 150dpi.jpg.]]

The next mission to return extraterrestrial samples was the Genesis mission, which returned solar wind samples to Earth from beyond Earth orbit in 2004. Unfortunately, the Genesis capsule failed to open its parachute while re-entering the Earth's atmosphere and crash-landed in the Utah desert. There were fears of severe contamination or even total mission loss, but scientists managed to save many of the samples. They were the first to be collected from beyond lunar orbit. Genesis used a collector array made of wafers of ultra-pure silicon, gold, sapphire, and diamond. Each different wafer was used to collect a different part of the solar wind.{{cite web|title=A Little Glitz Goes a Long Way for NASA's Genesis|date=3 September 2004|url=https://www.nasa.gov/mission_pages/genesis/media/feature-glitz-090304.html|publisher=NASA|access-date=3 March 2023}}

File:Stardust Capsule on Ground.jpg mission]]

Genesis was followed by NASA's Stardust spacecraft, which returned comet samples to Earth on 15 January 2006. It safely passed by Comet Wild 2 and collected dust samples from the comet's coma while imaging the comet's nucleus. Stardust used a collector array made of low-density aerogel (99% of which is space), which has about 1/1000 of the density of glass. This enables the collection of cometary particles without damaging them due to high impact velocities. Particle collisions with even slightly porous solid collectors would result in the destruction of those particles and damage to the collection apparatus. During the cruise, the array collected at least seven interstellar dust particles.{{cite journal | last1=Westphal | first1=A. | last2=Stroud | first2=R.|author2-link= Rhonda Stroud |display-authors=etal | title=Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft | journal=Science | volume=345 | issue=6198 | pages=786–91 | date=15 Aug 2014 | bibcode=2014Sci...345..786W | doi=10.1126/science.1252496 | pmid=25124433 | hdl=2381/32470 | s2cid=206556225 | url=https://figshare.com/articles/journal_contribution/10129433 | hdl-access=free }}

=2010s and 2020s=

In June 2010 the Japan Aerospace Exploration Agency (JAXA) Hayabusa probe returned asteroid samples to Earth after a rendezvous with (and a landing on) S-type asteroid 25143 Itokawa. In November 2010, scientists at the agency confirmed that, despite failure of the sampling device, the probe retrieved micrograms of dust from the asteroid, the first brought back to Earth in pristine condition.{{cite news|url=https://www.bbc.co.uk/news/science-environment-11763484|title=Japan probe collected particles from Itokawa asteroid|first=Jonathan|last=Amos|work=BBC News|date=16 November 2010|access-date=16 November 2010}}

The Russian Fobos-Grunt was a failed sample-return mission designed to return samples from Phobos, one of the moons of Mars. It was launched on 8 November 2011, but failed to leave Earth orbit and crashed after several weeks into the southern Pacific Ocean.{{cite web |url=http://www.planetary.org/blog/article/00003327/ |title=Bruce Betts: Reflections on Phobos LIFE |author=Emily Lakdawalla |date=13 January 2012 |work=The Planetary Society Blog |access-date=17 March 2012}}{{cite news|url=https://www.nytimes.com/2012/01/16/science/space/russias-phobos-grunt-mars-probe-crashes-into-pacific.html|title=Russia's Failed Mars Probe Crashes Into Pacific|first=Andrew|last=Kramer|newspaper=The New York Times |date=15 January 2012|access-date=16 January 2012}}

File:OSIRIS-REX SamCam TAGSAM Event 2020-10-20 small.gif
— (Full-sized image)]]

File:Maps14227-fig-0005-m.jpg

The Japan Aerospace Exploration Agency (JAXA) launched the improved Hayabusa2 space probe on 3 December 2014. Hayabusa2 arrived at the target near-Earth C-type asteroid 162173 Ryugu (previously designated {{mpl|1999 JU|3}}) on 27 June 2018.{{Cite web|url=https://spaceflightnow.com/2018/06/28/japanese-spacecraft-reaches-asteroid-after-three-and-a-half-year-journey/|title=Japanese spacecraft reaches asteroid after three-and-a-half-year journey – Spaceflight Now|website=spaceflightnow.com|language=en-US|access-date=2018-09-23}} It surveyed the asteroid for a year and a half and took samples. It left the asteroid in November 2019{{cite news|last=Bartels|first=Meghan|url=https://www.space.com/hayabusa2-spacecraft-leaves-asteroid-ryugu.html|title=Farewell, Ryugu! Japan's Hayabusa2 Probe Leaves Asteroid for Journey Home|date=2019-11-13|work=Space.com}}{{cite press release|date=14 July 2020|title=Joint Statement for Cooperation in the Hayabusa2 Sample Return Mission by the Australian Space Agency and the Japan Aerospace Exploration Agency |url=https://www.jaxa.jp/press/2020/07/20200714-1_j.html|publisher=JAXA|access-date=14 July 2020}} and returned to Earth on 6 December 2020.{{cite news |title=Hayabusa-2: Capsule with asteroid samples in 'perfect' shape |website=BBC News |date=5 December 2020 |archive-url=https://web.archive.org/web/20230713195350/https://www.bbc.com/news/science-environment-55201662 |archive-date=2023-07-13 |url-status=live |url=https://www.bbc.com/news/science-environment-55201662}}

The OSIRIS-REx mission was launched in September 2016 on a mission to return samples from the asteroid 101955 Bennu.{{cite web|url=https://www.nasa.gov/press-release/nasa-s-osiris-rex-speeds-toward-asteroid-rendezvous |title=NASA's OSIRIS-REx Speeds Toward Asteroid Rendezvous |publisher=NASA|date=9 September 2016|access-date=9 September 2016}}{{cite web|url=https://www.bbc.co.uk/news/science-environment-37309903 |title=Asteroid probe begins seven-year quest |publisher=BBC News|date=9 September 2016|access-date=9 September 2016}} The samples are expected to enable scientists to learn more about the time before the birth of the Solar System, initial stages of planet formation, and the source of organic compounds that led to the formation of life.{{cite web|title=NASA To Launch New Science Mission To Asteroid In 2016|url=http://www.nasa.gov/home/hqnews/2011/may/HQ_11-163_New_Frontier.html|publisher=NASA}} It reached the proximity of Bennu on 3 December 2018,{{cite news | url = https://www.nytimes.com/2018/12/03/science/osiris-rex-bennu-asteroid-arrival.html | title= NASA's Osiris-Rex Arrives at Asteroid Bennu After a Two-Year Journey | first= Kenneth | last = Chang | date = 3 December 2018 | access-date = 3 December 2018 | newspaper = The New York Times }} where it began analyzing its surface for a target sample area over the next several months. It collected its sample on 20 October 2020,{{Cite web|last=Potter|first=Sean|date=2020-10-20|title=NASA's OSIRIS-REx Spacecraft Successfully Touches Asteroid|url=http://www.nasa.gov/press-release/nasa-s-osiris-rex-spacecraft-successfully-touches-asteroid|access-date=2020-10-21|website=NASA}}{{Cite web|title=NASA's OSIRIS-REx Successfully Stows Sample of Asteroid Bennu|url=https://www.asteroidmission.org/?latest-news=nasas-osiris-rex-successfully-stows-sample-of-asteroid-bennu|access-date=2020-11-29|website=OSIRIS-REx Mission|language=en-US}} and landed back on Earth again on 24 September 2023, making OSIRIS-REx the fifth successful sample return mission for mankind, in its return of samples from an extra-terrestrial body.{{cite news |last=Miller |first=Katrina |title=A NASA Spacecraft Comes Home With an Asteroid Gift for Earth - The seven-year OSIRIS-REX mission ended on Sunday [9/23/2023] with the return of regolith from the asteroid Bennu, which might hold clues about the origins of our solar system and life. + comment |url=https://www.nytimes.com/2023/09/24/science/nasa-osiris-rex-asteroid-sample-landing.html#permid=127970460 |date=24 September 2023 |work=The New York Times |url-status=live |archiveurl=https://ghostarchive.org/archive/b1Z0E |archivedate=25 September 2023 |accessdate=25 September 2023 }}{{cite web |url=https://blogs.nasa.gov/osiris-rex/2023/09/24/capsule-containing-asteroid-bennu-sample-has-landed/|title=Capsule Containing Asteroid Bennu Sample Has Landed |publisher=NASA |date=24 September 2023}}{{cite news |last=Chang |first=Kenneth |title=Bye-Bye, Bennu: NASA Heads Back to Earth With Asteroid Stash in Tow - The OSIRIS-REX mission will spend two years cruising home with space rock samples that could unlock secrets of the early solar system. |url=https://www.nytimes.com/2021/05/10/science/nasa-osiris-rex-asteroid.html|date=10 May 2021 |work=The New York Times |accessdate=11 May 2021 }}{{cite web |url=https://ehpd.gsfc.nasa.gov/documents/552572main_OSIRIS_REx_Factsheet.pdf |title=OSIRIS-REx Factsheet |publisher=NASA/Explorers and Heliophysics Projects Division |date=August 2011}} Shortly after the sample container was retrieved and transferred to an "airtight chamber at the Johnson Space Center in Houston, Texas", the lid on the container was opened. Scientists commented that they "found black dust and debris on the avionics deck of the OSIRIS-REx science canister" on the initial opening. Later study was planned. On 11 October 2023, the recovered capsule was opened to reveal a "first look" at the asteroid sample contents.{{cite news |author=Staff |title=Likely asteroid debris found upon opening of returned NASA probe |url=https://phys.org/news/2023-09-asteroid-debris-nasa-probe.html |date=27 September 2023 |work=Phys.org |url-status=live |archiveurl=https://archive.today/20230927134525/https://phys.org/news/2023-09-asteroid-debris-nasa-probe.html |archivedate=27 September 2023| accessdate=27 September 2023 }}{{cite news |last=Chang |first=Kenneth |title=NASA Unveils First Glimpse of 'Scientific Treasure' Collected From Asteroid - Scientists said they got more material than expected from the Osiris-Rex mission during its seven-year journey to the asteroid Bennu. |url=https://www.nytimes.com/2023/10/11/science/nasa-asteroid-osiris-rex-bennu.html |date=11 October 2023 |work=The New York Times |url-status=live |archiveurl=https://archive.today/20231011174611/https://www.nytimes.com/2023/10/11/science/nasa-asteroid-osiris-rex-bennu.html |archivedate=11 October 2023 |accessdate=12 October 2023 }} On 13 December 2023, further studies of the returned sample were reported and revealed organic molecules as well as unknown materials which require more study to have a better idea of their composition and makeup.{{cite news |last=Kuthunur |first=Sharmila |title='What is that material?': Potentially hazardous asteroid Bennu stumps scientists with its odd makeup - Scientists found signs of organic molecules in the first samples of potentially hazardous asteroid Bennu, as well as a 'head scratching' material that has yet to be identified. |url=https://www.livescience.com/space/space-exploration/what-is-that-material-potentially-hazardous-asteroid-bennu-stumps-scientists-with-its-odd-makeup |date=13 December 2023 |work=LiveScience |url-status=live |archiveurl=https://archive.today/20231214014121/https://www.livescience.com/space/space-exploration/what-is-that-material-potentially-hazardous-asteroid-bennu-stumps-scientists-with-its-odd-makeup |archivedate=14 December 2023 |accessdate=13 December 2023 }}{{cite news |last=Rabie |first=Passant |title=It's Been 2 Months. Why Can't NASA Open the Asteroid Sample Container? - The space agency is having to develop new tools to crack open the canister containing bits from asteroid Bennu |url=https://gizmodo.com/nasa-osiris-rex-asteroid-samples-bennu-stuck-container-1851102598 |date=15 December 2023 |work=Gizmodo |url-status=live |archiveurl=https://archive.today/20231215230642/https://gizmodo.com/nasa-osiris-rex-asteroid-samples-bennu-stuck-container-1851102598 |archivedate=15 December 2023 |accessdate=16 December 2023 }} On 13 January 2024, NASA reported finally fully opening, after three months of trying, the recovered container with samples from the Bennu asteroid.{{cite news |last=MacDonald |first=Cheyenne |title=NASA finally got the stuck lid off its asteroid Bennu sample container - Thanks to some stubborn fasteners, the agency spent three months locked out of the sample OSIRIS-REx dropped off. |url=https://www.engadget.com/nasa-finally-got-the-stuck-lid-off-its-asteroid-bennu-sample-container-185814782.html |date=13 January 2024 |work=Engadget |url-status=live |archiveurl=https://archive.today/20240114015754/https://www.engadget.com/nasa-finally-got-the-stuck-lid-off-its-asteroid-bennu-sample-container-185814782.html |archivedate=14 January 2024 |accessdate=13 January 2024 }}{{cite news |last=Rabie |first=Passant |title=NASA Finally Opened the Asteroid Container and Holy Crap That's a Lot of Asteroid - After months of struggling to get to the bulk of the OSIRIS-REx asteroid sample, the space agency has unveiled a treasure trove of ancient rocks and dust. |url=https://gizmodo.com/nasa-osiris-rex-canister-reveal-asteroid-sample-trove-1851184737 |date=22 January 2024 |work=Gizmodo |url-status=live |archiveurl=https://archive.today/20240123011843/https://gizmodo.com/nasa-osiris-rex-canister-reveal-asteroid-sample-trove-1851184737 |archivedate=23 January 2024 |accessdate=22 January 2024 }} The total weight of the recovered material weighed {{convert|121.6|g|oz|abbr=on}}, over twice the mission's goal.{{cite news |last=Rabie |first=Passant |title=We Finally Know How Much of That Asteroid OSIRIS-REx Grabbed in Space - Engineers struggled to open the sample canister for months, but it was all worth it for twice the amount of asteroid they thought they were getting. |url=https://gizmodo.com/how-much-nasa-osiris-rex-collected-asteroid-space-1851261317 |date=15 February 2024 |work=Gizmodo |url-status=live |archiveurl=https://archive.today/20240216145102/https://gizmodo.com/how-much-nasa-osiris-rex-collected-asteroid-space-1851261317 |archivedate=16 February 2024 |accessdate=16 February 2024 }}

File:Chang'e-6 lunar regolith.jpg mission.]]

China's CNSA launched the Chang'e 5 and 6 lunar sample-return mission on 23 November 2020 and 3 May 2024 respectively, which returned to Earth with 2 kilograms of lunar soil each on 16 December 2020 and 25 June 2024 respectively.{{Cite web|date=2020-12-16|title=China recovers Chang'e-5 moon samples after complex 23-day mission|url=https://spacenews.com/china-recovers-change-5-moon-samples-after-complex-23-day-mission/|access-date=3 March 2023|website=SpaceNews|language=en-US}} These were the first lunar sample-return missions in over 40 years.{{Cite web|last=Jones|first=Andrew|date=28 November 2020|title=China's Chang'e 5 enters lunar orbit for historic attempt to return moon samples|url=https://www.space.com/china-chang-e-5-moon-sample-return-lunar-orbit|access-date=2020-11-29|website=Space.com|language=en}} The Chang'e 6 mission, which landed in the Apollo crater basin in the southern hemisphere of the lunar far side, was the first to retrieve samples from the far side of the Moon, as all previous collective lunar samples having been collected from the near side.{{Cite web |author1=Rahul Rao |date=2024-06-25 |title=China's Chang'e 6 probe will soon bring samples of the moon's far side to Earth — and scientists are getting excited |url=https://www.space.com/change-6-sample-return-science-investigations-scientists |access-date=2024-06-26 |website=Space.com |language=en}}

=Current missions=

CNSA's Tianwen-2 was launched in May 2025 with the aim to return samples from 469219 Kamoʻoalewa which was launched in 2025.{{Cite web |date=2021-08-10 |title=China Plans Near-Earth Asteroid Smash-and-Grab |url=https://spectrum.ieee.org/china-plans-near-earth-asteroid-smash-and-grab |access-date=2021-11-04 |website=IEEE Spectrum |language=en}}

= Future missions =

CNSA plans for a Mars sample return mission by 2030.{{cite web |url= http://news.xinhuanet.com/english/china/2012-10/10/c_123806897.htm|archive-url= https://web.archive.org/web/20121014035159/http://news.xinhuanet.com/english/china/2012-10/10/c_123806897.htm|url-status= dead|archive-date= 14 October 2012|title= China considers more Mars probes before 2030|author= English.news.cn|date=2012-10-10|access-date= 2012-10-14|work= news.xinhuanet.com}}{{cite web |url= http://www.marsdaily.com/reports/China_to_collect_samples_from_Mars_by_2030_Xinhua_999.html|title= China to collect samples from Mars by 2030: Xinhua|author= Staff Writers Beijing (AFP)|date=2012-10-10|access-date= 2012-10-14|work= marsdaily.com}} Also, the Chinese Space Agency is designing a sample-retrieval mission from Ceres that would take place during the 2020s.[http://english.nssc.cas.cn/ns/NU/201410/W020141016603613379886.pdf China's Deep-space Exploration to 2030] by Zou Yongliao Li Wei Ouyang Ziyuan Key Laboratory of Lunar and Deep Space Exploration, National Astronomical Observatories, Chinese Academy of Sciences, Beijing.

JAXA is developing the MMX mission, a sample-return mission to Phobos that will be launched in 2026.{{cite web|url=https://japannews.yomiuri.co.jp/science-nature/science/20231206-154061/|title=Japan to Delay Mars Moon Exploration by 2 Years to 2026|work=Yomiuri Shimbun|date=6 December 2023|access-date=26 December 2023}} MMX will study both moons of Mars, but the landing and the sample collection will be on Phobos. This selection was made because of the two moons, Phobos's orbit is closer to Mars and its surface may have particles blasted from Mars. Thus the sample may contain material originating on Mars itself.{{cite news |date=22 September 2017 |script-title=ja:火星衛星の砂回収へＪＡＸＡ「フォボス」に探査機 |url=https://www.nikkei.com/article/DGXLASDG22HAZ_S7A920C1CR8000/ |language=ja |newspaper=Nikkei |access-date=2018-07-20}} A propulsion module carrying the sample is expected to return to Earth in 2031.

NASA and ESA have long planned a Mars Sample-Return Mission.{{cite news |last=Chang |first=Kenneth |title=Bringing Mars Rocks to Earth: Our Greatest Interplanetary Circus Act - NASA and the European Space Agency plan to toss rocks from one spacecraft to another before the samples finally land on Earth in 2031. |url=https://www.nytimes.com/2020/07/28/science/mars-sample-return-mission.html |date=28 July 2020 |work=The New York Times |access-date=28 July 2020 }} The Perseverance rover, deployed in 2020, is collecting drill core samples and stashing them on the Mars surface.{{cite journal |last1=Voosen |first1=Paul |title=NASA's new rover will collect martian rocks—and clues to planet's ancient climate |url=https://www.science.org/content/article/nasa-s-new-rover-will-collect-martian-rocks-and-clues-planet-s-ancient-climate |journal=Science |publisher=American Association for the Advancement of Science |access-date=12 October 2020 |language=en |doi=10.1126/science.abd5006 |date=25 June 2020}} As of September 2023, it has gathered one atmospheric sample and 8 igneous rock samples, 11 sedimentary rock samples and a pair of regolith samples.{{Cite web|last=mars.nasa.gov|title=NASA's Perseverance Plans Next Sample Attempt|url=https://mars.nasa.gov/news/9022/nasas-perseverance-plans-next-sample-attempt|access-date=2021-08-27|website=NASA’s Mars Exploration Program|date=26 August 2021 |language=en}} On 22 November 2023, NASA announced that it was cutting back on the Mars sample-return mission due to a shortage of funds.{{cite news |last=Berg |first=Matt |date=22 November 2023 |title=Lawmakers 'mystified' after NASA scales back Mars collection program - The space agency's cut could "cost hundreds of jobs and a decade of lost science," the bipartisan group says. |url=https://www.politico.com/news/2023/11/22/lawmakers-mystified-after-nasa-scales-back-mars-collection-program-00128368 |url-status=live |archiveurl=https://archive.today/20231122162817/https://www.politico.com/news/2023/11/22/lawmakers-mystified-after-nasa-scales-back-mars-collection-program-00128368 |archivedate=22 November 2023 |accessdate=25 November 2023 |work=Politico}} In January 2024, the proposed NASA plan was challenged due to budget and scheduling considerations, and investigation into alternate plans begun.{{cite news |last=David |first=Leopnard |title=NASA's troubled Mars sample-return mission has scientists seeing red - Projected multibillion-dollar overruns have some calling the agency's plan a 'dumpster fire.' |url=https://www.space.com/nasa-troubled-mars-sample-return-mission-scientists-upset |date=15 January 2024 |work=Space.com |url-status=live |archiveurl=https://archive.today/20240116035224/https://www.space.com/nasa-troubled-mars-sample-return-mission-scientists-upset |archivedate=16 January 2024 |accessdate=16 January 2024 }}

Russia has plans for Luna-Glob missions to return samples from the Moon by 2027 and Mars-Grunt to return samples from Mars in the late 2020s.{{Cn|date=June 2023}}

Methods of sample return

File:Tagsamlast.gif

Sample-return methods include, but are not restricted to the following:

File:Genesis Collector Array.jpg

=Collector array=

A collector array may be used to collect millions or billions of atoms, molecules, and fine particulates by using wafers made of different elements. The molecular structure of these wafers allows the collection of various sizes of particles. Collector arrays, such as those flown on Genesis, are ultra-pure in order to ensure maximal collection efficiency, durability, and analytical distinguishability.{{fact|date=November 2024}}

Collector arrays are useful for collecting tiny, fast-moving atoms such as those expelled by the Sun through the solar wind, but can also be used for collection of larger particles such as those found in the coma of a comet. The NASA spacecraft known as Stardust implemented this technique. However, due to the high speeds and size of the particles that make up the coma and the area nearby, a dense solid-state collector array was not viable. As a result, another means for collecting samples had to be designed to preserve the safety of the spacecraft and the samples themselves.{{fact|date=November 2024}}

== Aerogel ==

File:Meteoroid track through aerogel from EURECA mission.jpg

Aerogel is a silica-based porous solid with a sponge-like structure, 99.8% of whose volume is empty space. Aerogel has about 1/1000 of the density of glass. An aerogel was used in the Stardust spacecraft because the dust particles the spacecraft was to collect would have an impact speed of about 6 km/s. A collision with a dense solid at that speed could alter their chemical composition or vaporize them completely.{{Cite web |title=Stardust - NASA's Comet Sample Return Mission: Aerogel |url=https://solarsystem.nasa.gov/stardust/tech/aerogel.html |access-date=2023-08-16 |website=solarsystem.nasa.gov}}

Since the aerogel is mostly transparent, and the particles leave a carrot-shaped path once they penetrate the surface, scientists can easily find and retrieve them. Since its pores are on the nanometer scale, particles, even ones smaller than a grain of sand, do not merely pass through the aerogel completely. Instead, they slow to a stop and then are embedded within it. The Stardust spacecraft has a tennis-racket-shaped collector with aerogel fitted to it. The collector is retracted into its capsule for safe storage and delivery back to Earth. Aerogel is quite strong and easily survives both launching and space environments.

=Robotic excavation and return=

Some of the riskiest and most difficult types of sample-return missions are those that require landing on an extraterrestrial body such as an asteroid, moon, or planet. It takes a great deal of time, money, and technical ability to even initiate such plans. It is a difficult feat that requires that everything from launch to landing to retrieval and launch back to Earth is planned out with high precision and accuracy.{{fact|date=November 2024}}

This type of sample return, although having the most risks, is the most rewarding for planetary science. Furthermore, such missions carry a great deal of public outreach potential, which is an important attribute for space exploration when it comes to public support. The only successful robotic sample-return missions of this type have been Soviet Luna and Chinese Chang'e lunar landers. While other missions collected materials from asteroids by various means, they did so without "landing", given their very low gravity.{{fact|date=November 2024}}

List of missions

File:Lunar sample return map 2024.jpg

=Crewed missions=

class="wikitable sortable sticky-header"

! Launch date

! Operator

! Name

! Sample origin

! Samples returned

! Recovery date

! Mission result

| {{Flag|United States}}

| Apollo 11

| Moon

| {{Convert|22|kg}}

| {{Dts|24 July 1969}}

| {{success}}

| {{flagicon|United States}} United States

| Apollo 12

| Moon

| {{Convert|34|kg}} and Surveyor 3 parts{{NoteTag|The Apollo 12 astronauts removed several components from Surveyor 3, including the television camera, and returned them to Earth, where they are treated as lunar samples by NASA. It returned about {{Convert|10|kg}} of the Surveyor 3's original landing mass of {{Convert|302|kg}} to Earth to study the effects of long term exposure. Surveyor 3 is the only probe visited by humans on another world.}}{{cite web |title=Surveyor 2 parts brought by Apollo 12 |url=http://www.collectspace.com/news/news-112219a-apollo-12-surveyor-parts-50-years.html|website=www.collectspace.com |language=en}}

| {{Dts|24 November 1969}}

| {{success}}

| {{flagicon|United States}} United States

| Apollo 13

| Moon

| {{n/a}}

| {{Dts|17 April 1970}}

| {{failure}}

| {{flagicon|United States}} United States

| Apollo 14

| Moon

| {{Convert|43|kg}}

| {{Dts|9 February 1971}}

| {{success}}

| {{flagicon|United States}} United States

| Apollo 15

| Moon

| {{Convert|77|kg}}

| {{Dts|7 August 1971}}

| {{success}}

| {{flagicon|United States}} United States

| Apollo 16

| Moon

| {{Convert|95|kg}}

| {{Dts|27 April 1972}}

| {{success}}

| {{flagicon|United States}} United States

| Apollo 17

| Moon

| {{Convert|111|kg}}

| {{Dts|19 December 1972}}

| {{success}}

| {{Flag|Russia}}

| Earth-Orbital Debris Collection

| Low Earth orbit

| {{Sort|0|Particles}}

| {{Dts|6 October 1997}}

| {{success}}{{cite web|url=http://www.spacedaily.com/news/debris-99a.html|title=Mir Orbital Debris Collector Data Analyzed|website=Spacedaily.com|access-date=8 July 2018}}

| {{Flagicon|Japan}} Japan

| Tanpopo mission

| Low Earth orbit

| {{Sort|0|Particles}}

| {{Dts|February 2018}}{{cite web |title=NASA - Astrobiology Exposure and Micrometeoroid Capture Experiments |url=https://www.nasa.gov/mission_pages/station/research/experiments/2201.html|website=www.nasagov.com |language=en}}

| {{success}}

=Robotic missions=

class="wikitable sortable sticky-header"

! Launch date

! Operator

! Name

! Sample origin

! Samples returned

! Recovery date

! Mission result

| {{Flag|Soviet Union}}

| Luna E-8-5 No. 402

| Moon

| {{n/a}}

| {{failure}}