Editing Planetary engineering (section)

=== Technologies ===
A common object of discussion on potential terraforming is the planet Mars. To terraform Mars, humans would need to create a new atmosphere, due to the planet's high carbon dioxide concentration and low atmospheric pressure. This would be possible by introducing more greenhouse gases to below "freezing point from indigenous materials".<ref name="Pollack & Sagan 1993">{{cite book |last1=Pollack |first1=James B. |last2=Sagan |first2=Carl |chapter=Planetary engineering |pages=921–950 |chapter-url=http://www.uapress.arizona.edu/onlinebks/ResourcesNearEarthSpace/resources33.pdf |archive-url=https://web.archive.org/web/20100624205541/http://www.uapress.arizona.edu/onlinebks/ResourcesNearEarthSpace/resources33.pdf |archive-date=24 June 2010 |editor1-last=Lewis |editor1-first=John S. |editor2-last=Matthews |editor2-first=Mildred Shapley |editor3-last=Guerrieri |editor3-first=Mary L. |title=Resources of Near-Earth Space |date=1993 |publisher=University of Arizona Press |isbn=978-0-8165-1404-5 }}</ref> To terraform Venus, carbon dioxide would need to be converted to graphite since Venus receives twice as much sunlight as Earth. This process is only possible if the greenhouse effect is removed with the use of "high-altitude absorbing fine particles" or a sun shield, creating a more habitable Venus.<ref name="Pollack & Sagan 1993"/>

NASA has defined categories of habitability systems and technologies for terraforming to be feasible.<ref name=":1">{{Cite web |title=Habitats, Habitability, and Human Factors |url=https://sbir.nasa.gov/content/habitats-habitability-and-human-factors |access-date=5 November 2021 |website=NASA SBIR & STTR Program |archive-date=27 October 2021 |archive-url=https://web.archive.org/web/20211027102422/https://sbir.nasa.gov/content/habitats-habitability-and-human-factors |url-status=live }}</ref> These topics include creating power-efficient systems for preserving and packaging  food for crews, preparing and cooking foods, dispensing water, and developing facilities for rest, trash and recycling, and areas for crew hygiene and rest.<ref name=":1" />