Editing Titan (moon) (section)

=== ''Cassini–Huygens'' ===
{{Main|Cassini–Huygens|Huygens (spacecraft)}}

The ''Cassini–Huygens'' spacecraft reached Saturn on July 1, 2004,<ref name="p964">{{cite web | title=Approach and Arrival at Saturn | website=[[ESA Science & Technology]] | date=June 11, 2004 | url=https://sci.esa.int/web/cassini-huygens/-/34955-approach-and-arrival | access-date=August 8, 2024}}</ref> and began the process of mapping Titan's surface by [[radar]].<ref name="n137">{{cite web | last1=Rodriguez | first1=S. | last2=Crapeau | first2=M. | last3=Mouelic | first3=S. Le | last4=Paillou | first4=Philippe | last5=Baines | first5=K. H. | title=Cassini VIMS and Altimeter joint study of Titan surface | website=ResearchGate | date=March 11, 2007 | url=https://www.researchgate.net/publication/29607391 | access-date=August 8, 2024}}</ref> A joint project of the [[European Space Agency]] (ESA) and [[NASA]], ''Cassini–Huygens'' proved a very successful mission.<ref name="y419">{{cite web | title=Cassini-Huygens | website=NASA Jet Propulsion Laboratory | date=October 15, 1997 | url=https://www.jpl.nasa.gov/missions/cassini-huygens | access-date=August 8, 2024}}</ref> The ''Cassini'' probe flew by Titan on October 26, 2004, and took the highest-resolution images ever of Titan's surface, at only 1,200 km (750 mi), discerning patches of light and dark that would be invisible to the human eye.<ref name="r979"/>

On July 22, 2006, ''Cassini'' made its first targeted, close fly-by at 950 km (590 mi) from Titan; the closest flyby was at 880 km (550 mi) on June 21, 2010.<ref>{{cite web |title=Cassini Equinox Mission: Titan Flyby (T-70) – June 21, 2010 |publisher=NASA/JPL |url=https://saturn.jpl.nasa.gov/mission/flybys/titan20100621/ |access-date=July 8, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20120318223434/https://saturn.jpl.nasa.gov/mission/flybys/titan20100621/ |archive-date=March 18, 2012 }}</ref> Liquid has been found in abundance on the surface in the north polar region, in the form of many lakes and seas discovered by ''Cassini''.<ref name="PIA08630" />

==== ''Huygens'' landing ====
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| caption1          = ''Huygens'' ''[[in situ]]'' image from Titan's surface—the only image from the surface of a body permanently farther away than Mars
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<!-- [[File:Huygens surface color.jpg|thumb|upright|''Huygens'' image ''in situ'' from Titan's surface—the only image from the surface of a planetary body outside the inner Solar system]]
[[File:Huygens surface color sr.jpg|thumb|upright|Same with different data processing]] -->

''Huygens'' was an atmospheric probe that touched down on Titan on January 14, 2005,<ref>{{cite journal |first1=Steve |last1=Lingard |last2=Norris |first2=Pat |url=https://www.ingenia.org.uk/Ingenia/Articles/7cf998f7-b886-42b7-8f1e-4596af1354e8 |title=How To Land on Titan |issue=23 |date=June 2005 |journal=Ingenia Magazine|access-date=January 11, 2009 |url-status=live |archive-url=https://web.archive.org/web/20110721163014/https://www.ingenia.org.uk/ingenia/articles.aspx?Index=317 |archive-date=July 21, 2011 }}</ref> discovering that many of its surface features seem to have been formed by fluids at some point in the past.<ref name="huygens_picture_saturn">{{cite web |url=https://saturn.jpl.nasa.gov/operations/index.cfm |title=Cassini at Saturn: Introduction |access-date=September 6, 2007 |publisher=NASA, Jet Propulsion Laboratory |url-status=dead |archive-url=https://web.archive.org/web/20090403131313/https://saturn.jpl.nasa.gov/operations/index.cfm |archive-date=April 3, 2009 }}</ref> Titan is the most distant body from Earth to have a space probe land on its surface.<ref>{{cite web |url=https://www.spacetoday.org/SolSys/Saturn/SaturnHuygens.html |title=Huygens Exposes Titan's Surface |access-date=August 19, 2007 |work=Space Today |url-status=live |archive-url=https://web.archive.org/web/20110807190437/https://www.spacetoday.org/SolSys/Saturn/SaturnHuygens.html |archive-date=August 7, 2011 }}</ref>
[[File:Huygens descent.ogv|thumb|The ''[[Huygens (spacecraft)|Huygens]]'' probe descends by parachute and lands on Titan on January 14, 2005]]
The [[Huygens probe|''Huygens'' probe]] landed just off the easternmost tip of a bright region now called [[Adiri (Titan)|Adiri]]. The probe photographed pale hills with dark "rivers" running down to a dark plain. Current understanding is that the hills (also referred to as highlands) are composed mainly of water ice. Dark organic compounds, created in the upper atmosphere by the ultraviolet radiation of the Sun, may rain from Titan's atmosphere. They are washed down the hills with the methane rain and are deposited on the plains over geological time scales.<ref name="Seeing_Touching_Titan-ESA">{{cite news |url=https://www.esa.int/SPECIALS/Cassini-Huygens/SEMHB881Y3E_0.html |title=Seeing, touching and smelling the extraordinarily Earth-like world of Titan |publisher=ESA News, European Space Agency |date=January 21, 2005 |access-date=March 28, 2005 |url-status=live |archive-url=https://web.archive.org/web/20111007111129/https://www.esa.int/SPECIALS/Cassini-Huygens/SEMHB881Y3E_0.html |archive-date=October 7, 2011 }}</ref>

After landing, ''Huygens'' photographed a dark plain covered in small rocks and pebbles, which are composed of water ice.<ref name="Seeing_Touching_Titan-ESA" /> The two rocks just below the middle of the image on the right are smaller than they may appear: the left-hand one is 15&nbsp;centimeters across, and the one in the center is 4&nbsp;centimeters across, at a distance of about 85&nbsp;centimeters from ''Huygens''. There is evidence of [[erosion]] at the base of the rocks, indicating possible [[fluvial]] activity. The ground surface is darker than originally expected, consisting of a mixture of water and hydrocarbon ice.<ref>{{cite web|url=https://photojournal.jpl.nasa.gov/catalog/PIA07232|title=PIA07232: First Color View of Titan's Surface|publisher=NASA/JPL/ESA/University of Arizona|date=January 15, 2005|access-date=February 13, 2021|archive-date=May 6, 2021|archive-url=https://web.archive.org/web/20210506114620/https://photojournal.jpl.nasa.gov/catalog/PIA07232|url-status=live}}</ref>

In March 2007, NASA, ESA, and [[COSPAR]] decided to name the ''Huygens'' landing site the ''[[Hubert Curien]] Memorial Station'' in memory of the former president of the ESA.<ref>{{cite web |url=https://www.esa.int/esaCP/SEM9GNN0LYE_index_0.html |title=Huygens landing site to be named after Hubert Curien |publisher=ESA |date=March 5, 2007 |access-date=August 6, 2007 |url-status=live |archive-url=https://web.archive.org/web/20120303201334/https://www.esa.int/esaCP/SEM9GNN0LYE_index_0.html |archive-date=March 3, 2012 }}</ref>