Editing Artificial gravity (section)

===Differences from normal gravity===
[[Image:ArtificialGravity.gif|right|thumb|Balls in a rotating spacecraft]]

From the perspective of people rotating with the habitat, artificial gravity by rotation behaves similarly to normal gravity but with the following differences, which can be mitigated by increasing the radius of a space station.
* Centrifugal force varies with distance: Unlike real gravity, the apparent force felt by observers in the habitat pushes radially outward from the axis, and the centrifugal force is directly proportional to the distance from the axis of the habitat. With a small radius of rotation, a standing person's head would feel significantly less gravity than their feet.<ref name="symp1973">{{Cite conference |last=Stone |first=Ralph W. |date=August 1970 |title=An Overview of Artificial Gravity |url=https://ntrs.nasa.gov/api/citations/19740010641/downloads/19740010641.pdf#page=35 |conference=Fifth Symposium on the Role of the Vestibular Organs in Space Exploration |location=Naval Aerospace Medical Institute, Pensacola, Florida |publisher=[[NASA]] |page=25 |oclc=4200952 |id=SP-314 |archive-url=https://web.archive.org/web/20240415123635/https://ntrs.nasa.gov/api/citations/19740010641/downloads/19740010641.pdf#page=35 |archive-date=April 15, 2024 |hdl=2060/19740010641 |url-status=live }}</ref> Likewise, passengers who move in a space station experience changes in apparent weight in different parts of the body.<ref name="davis1994">{{Cite journal |last1=Davis |first1=BL |last2=Cavanagh |first2=PR |last3=Perry |first3=JE |date=September 1994 |title=Locomotion in a rotating space station: a synthesis of new data with established concepts |journal=Gait & Posture |volume=2 |issue=3 |pages=157–165 |doi=10.1016/0966-6362(94)90003-5 |issn=0966-6362 |pmid=11539277 }}</ref>
* The [[Coriolis effect]] gives an apparent force that acts on objects that are moving relative to a rotating reference frame. This apparent force acts at right angles to the motion and the rotation axis and tends to curve the motion in the opposite sense to the habitat's spin. If an [[astronaut]] inside a rotating artificial gravity environment moves towards or away from the axis of rotation, they will feel a force pushing them in or against the direction of spin. These forces act on the [[semicircular canals]] of the inner ear and can cause [[dizziness]].<ref name="alfred1969">{{Cite tech report |last1=Larson |first1=Carl Alfred |url=https://ntrs.nasa.gov/api/citations/19690029825/downloads/19690029825.pdf |title=Rotating Space Station Stabilization Criteria for Artificial Gravity |date=October 1969 |publisher=[[NASA]] |id=NASA-TN-D-5426 |archive-url=https://web.archive.org/web/20240815073410/https://ntrs.nasa.gov/api/citations/19690029825/downloads/19690029825.pdf |archive-date=August 15, 2024 |url-status=live |hdl=2060/19690029825 }}</ref> Lengthening the period of rotation (lower spin rate) reduces the Coriolis force and its effects. It is generally believed that at 2&nbsp;[[Revolutions per minute|rpm]] or less, no adverse effects from the Coriolis forces will occur, although humans have been shown to adapt to rates as high as 23&nbsp;[[Revolutions per minute|rpm]].<ref name=hecht2002>{{cite journal |title=Adapting to artificial gravity (AG) at high rotational speeds |journal = Life in Space for Life on Earth|volume = 23|pages = P1-5|author=Hecht, H. |author2=Brown, E. L. |author3=Young, L. R. |name-list-style=amp|publisher=Proceedings of "Life in space for life on Earth". 8th European Symposium on Life Sciences Research in Space. 23rd Annual International Gravitational Physiology Meeting |date=June 2–7, 2002 |issue = 1|pmid = 14703662|display-authors=etal|bibcode = 2002ESASP.501..151H}}</ref>
* Changes in the rotation axis or rate of a spin would cause a disturbance in the artificial gravity field and stimulate the semicircular canals (refer to above). Any movement of mass within the station, including a movement of people, would shift the axis and could potentially cause a dangerous wobble. Thus, the rotation of a space station would need to be adequately stabilized, and any operations to deliberately change the rotation would need to be done slowly enough to be imperceptible.<ref name="alfred1969"/> One possible solution to prevent the station from wobbling would be to use its liquid water supply as [[ballast]] which could be pumped between different sections of the station as required. 

[[File: RotationSpeedOfCentrifuge.svg|thumb|Speed in [[Revolutions per minute|rpm]] for a centrifuge of a given radius to achieve a given ''g''-force]]