Editing Moon (section)

===Surface conditions===
[[File:AS17-145-22224.jpg|thumb|[[Gene Cernan]] with [[lunar dust]] stuck on his suit. Lunar dust is highly abrasive and can cause damage to human lungs and nervous and cardiovascular systems.<ref>{{Cite web |last1=James |first1=John |last2=Kahn-Mayberry |first2=Noreen |date=Jan 2009 |title=Risk of Adverse Health Effects from Lunar Dust Exposure |url=https://humanresearchroadmap.nasa.gov/evidence/reports/lunar%20dust.pdf |access-date=December 8, 2022 |archive-date=December 4, 2021 |archive-url=https://web.archive.org/web/20211204004317/https://humanresearchroadmap.nasa.gov/evidence/reports/lunar%20dust.pdf |url-status=live}}</ref>]]
[[Ionizing radiation]] from [[cosmic ray]]s, their resulting [[neutron radiation]],<ref name="Science Mission Directorate 2005">{{cite web|date=September 8, 2005|title=Radioactive Moon|url=https://science.nasa.gov/science-news/science-at-nasa/2005/08sep_radioactivemoon#:~:text=Not%20so.,lunar%20surface%20itself%20is%20radioactive!|url-status=deviated|archive-url=https://web.archive.org/web/20191102123953/https://science.nasa.gov/science-news/science-at-nasa/2005/08sep_radioactivemoon/#:~:text=Not%20so.,lunar%20surface%20itself%20is%20radioactive!|archive-date=November 2, 2019|access-date=July 28, 2022|website=Science Mission Directorate}}</ref> and the Sun results in an average radiation level of 1.369 [[millisievert]]s per day during lunar [[daytime]],<ref name="surface-radiation"/> which is about 2.6 times more than the level on the [[International Space Station]], 5{{endash}}10 times more than the level during a trans-Atlantic flight, and 200 times more than the level on Earth's surface.<ref name="ScienceAlert 2020">{{cite web |date=September 26, 2020 |title=We Finally Know How Much Radiation There Is on The Moon, And It's Not Great News |url=https://www.sciencealert.com/scientists-predict-how-long-humans-can-survive-radiation-on-the-moon |url-status=live |archive-url=https://web.archive.org/web/20220728004319/https://www.sciencealert.com/scientists-predict-how-long-humans-can-survive-radiation-on-the-moon |archive-date=July 28, 2022 |access-date=July 28, 2022 |website=ScienceAlert}}</ref> For further comparison, radiation levels average about 1.84 millisieverts per day on a [[Human mission to Mars|flight to Mars]] and about 0.64 millisieverts per day on Mars itself, with some locations on Mars possibly having levels as low as 0.342 millisieverts per day.<ref name="Paris Davies Tognetti Zahniser 2020">{{cite arXiv |last1=Paris |first1=Antonio |last2=Davies |first2=Evan |last3=Tognetti |first3=Laurence |last4=Zahniser |first4=Carly |title=Prospective Lava Tubes at Hellas Planitia |date=April 27, 2020 |class=astro-ph.EP |eprint=2004.13156v1}}</ref><ref name="Wall 2013">{{cite web |last=Wall |first=Mike |date=December 9, 2013 |title=Radiation on Mars 'Manageable' for Manned Mission, Curiosity Rover Reveals |url=https://www.space.com/23875-mars-radiation-life-manned-mission.html |access-date=August 7, 2022 |website=Space.com |archive-date=December 15, 2020 |archive-url=https://web.archive.org/web/20201215082045/https://www.space.com/23875-mars-radiation-life-manned-mission.html |url-status=live}}</ref>
Solar radiation also [[static electricity|electrically charges]] the highly abrasive [[lunar dust]] and makes it levitate. This effect contributes to the easy spread of the sticky, lung- and gear-damaging lunar dust.<ref name="e657">{{cite web |title=The toxic side of the Moon |website=ESA |url=https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/The_toxic_side_of_the_Moon |access-date=2025-01-07}}</ref>

The Moon's [[axial tilt]] with respect to the [[ecliptic]] is only 1.5427°,<ref name="SolarViews" /><ref>{{Cite journal |last1=Rambaux |first1=N. |last2=Williams |first2=J. G. |date=2011 |title=The Moon's physical librations and determination of their free modes |url=https://doi.org/10.1007/s10569-010-9314-2 |url-status=live |journal=Celestial Mechanics and Dynamical Astronomy |volume=109 |issue=1 |pages=85–100 |bibcode=2011CeMDA.109...85R |doi=10.1007/s10569-010-9314-2 |archive-url=https://web.archive.org/web/20220730084921/https://link.springer.com/article/10.1007/s10569-010-9314-2 |archive-date=July 30, 2022 |access-date=July 30, 2022 |s2cid=45209988}}</ref> much less than the 23.44° of Earth. This small axial tilt means that the Moon's solar illumination varies much less with [[season]] than Earth's, and it also allows for the existence of some [[peaks of eternal light]] at the [[Lunar north pole|Moon's north pole]], at the rim of the crater [[Peary (crater)|Peary]].

The lunar surface is exposed to drastic temperature differences ranging from {{val|120|u=°C}} to {{val|−171|u=°C}} depending on the [[solar irradiance]].
Because of the lack of atmosphere, temperatures of different areas vary particularly upon whether they are in sunlight or shadow,<ref>{{cite web |last=Rocheleau |first=Jake |date=May 21, 2012 |title=Temperature on the Moon – Surface Temperature of the Moon |url=http://planetfacts.org/temperature-on-the-moon/ |url-status=live |archive-url=https://web.archive.org/web/20150527194737/http://planetfacts.org/temperature-on-the-moon/ |archive-date=May 27, 2015 |website=PlanetFacts.org}}</ref> making topographical details play a decisive role on local [[Global surface temperature|surface temperature]]s.<ref name="bbc" />
Parts of many craters, particularly the bottoms of many polar craters,<ref name="M03" /> are permanently shadowed. These [[crater of eternal darkness|craters of eternal darkness]] have extremely low temperatures. The ''Lunar Reconnaissance Orbiter'' measured the lowest summer temperatures in craters at the southern pole at {{Convert|35 |K |4=0 |abbr=on}}<ref>{{cite web |date=September 17, 2009 |title=Diviner News |url=http://www.diviner.ucla.edu/blog/?p=123 |url-status=dead |archive-url=https://web.archive.org/web/20100307031354/http://www.diviner.ucla.edu/blog/?p=123 |archive-date=March 7, 2010 |access-date=March 17, 2010 |publisher=[[UCLA]]}}</ref> and just {{Convert |26 |K |4=0 |abbr=on}} close to the winter solstice in the north polar crater [[Hermite (crater)|Hermite]]. This is the coldest temperature in the Solar System ever measured by a spacecraft, colder even than the surface of [[Pluto]].<ref name="bbc" />

Blanketed on top of the Moon's crust is a highly [[Comminution|comminuted]] (broken into ever smaller particles) and [[impact gardening|impact gardened]] mostly gray surface layer called [[regolith]], formed by impact processes. The finer regolith, the [[lunar soil]] of [[silicon dioxide]] glass, has a texture resembling snow and a scent resembling spent [[gunpowder]].<ref>{{cite web |date=January 30, 2006 |title=The Smell of Moondust |url=https://science.nasa.gov/headlines/y2006/30jan_smellofmoondust.htm |url-status=dead |archive-url=https://web.archive.org/web/20100308112332/http://science.nasa.gov/headlines/y2006/30jan_smellofmoondust.htm |archive-date=March 8, 2010 |access-date=March 15, 2010 |publisher=NASA}}</ref> The regolith of older surfaces is generally thicker than for younger surfaces: it varies in thickness from {{convert|10|{{endash}}|15|m|abbr=on}} in the highlands and {{convert|4|{{endash}}|5|m|abbr=on}} in the maria.<ref>{{cite book |last=Heiken |first=G. |url=https://archive.org/details/lunarsourcebooku0000unse/page/286 |title=Lunar Sourcebook, a user's guide to the Moon |date=1991 |publisher=[[Cambridge University Press]] |isbn=978-0-521-33444-0 |editor1-last=Vaniman |editor1-first=D. |location=New York |page=[https://archive.org/details/lunarsourcebooku0000unse/page/286 286] |access-date=December 17, 2019 |editor2-last=French |editor2-first=B. |archive-url=https://web.archive.org/web/20200617181609/https://archive.org/details/lunarsourcebooku0000unse/page/736 |archive-date=June 17, 2020 |url-status=live}}</ref> Beneath the finely comminuted regolith layer is the megaregolith, a layer of highly fractured bedrock many kilometers thick.<ref>{{cite journal |last=Rasmussen |first=K.L. |author2=Warren, P.H. |date=1985 |title=Megaregolith thickness, heat flow, and the bulk composition of the Moon |journal=[[Nature (journal)|Nature]] |volume=313 |issue=5998 |pages=121–124 |bibcode=1985Natur.313..121R |doi=10.1038/313121a0 |s2cid=4245137}}</ref>

These extreme conditions are considered to make it unlikely for spacecraft to harbor bacterial spores at the Moon for longer than just one lunar orbit.<ref>{{cite journal |last1=Schuerger |first1=Andrew C. |last2=Moores |first2=John E. |last3=Smith |first3=David J. |last4=Reitz |first4=Günther |date=June 2019 |title=A Lunar Microbial Survival Model for Predicting the Forward Contamination of the Moon |journal=Astrobiology |volume=19 |issue=6 |pages=730–756 |bibcode=2019AsBio..19..730S |doi=10.1089/ast.2018.1952 |pmid=30810338 |s2cid=73491587 |doi-access=free}}</ref>