Editing Outer space (section)

===Regions near the Earth===
The outermost layer of the Earth's atmosphere is termed the [[exosphere]]. It extends outward from the [[thermopause]], which lies at an altitude that varies from {{convert|250|to|500|km|mi}}, depending on the incidence of solar radiation. Beyond this altitude, collisions between molecules are negligible and the atmosphere joins with interplanetary space.<ref name=Catling_Kasting_2017/> The region in proximity to the Earth is home to a multitude of Earth–orbiting satellites and has been subject to extensive studies. For identification purposes, this volume is divided into overlapping regions of space.<ref name="uscode.house.gov 2022"/>{{sfn|Schrijver|Siscoe|2010|p=363, 379}}<ref name=sdc20150426/><ref name=sr2165/>

'''{{Visible anchor|Near-Earth space}}''' is the region of space extending from low Earth orbits out to [[geostationary orbit]]s.<ref name="uscode.house.gov 2022"/> This region includes the major orbits for [[artificial satellite]]s and is the site of most of humanity's space activity. The region has seen high levels of space debris, sometimes dubbed [[space pollution]], threatening nearby space activity.<ref name="uscode.house.gov 2022"/> Some of this debris re-enters Earth's atmosphere periodically.<ref name=portree_loftus1999/> Although it meets the definition of outer space, the atmospheric density inside low-Earth orbital space, the first few hundred kilometers above the Kármán line, is still sufficient to produce significant [[Drag (physics)|drag]] on satellites.<ref name=slsa/>

[[File:Debris-GEO1280.jpg|thumb|A computer-generated map of objects orbiting Earth, as of 2005. About 95% are debris, not working artificial satellites<ref name=ARES/>]]

{{anchor|Geospace}}'''Geospace''' is a region of space that includes Earth's [[upper atmosphere]] and [[magnetosphere]].{{sfn|Schrijver|Siscoe|2010|p=363, 379}} The Van Allen radiation belts lie within the geospace. The outer boundary of geospace is the [[magnetopause]], which forms an interface between the Earth's magnetosphere and the solar wind. The inner boundary is the [[ionosphere]].<ref name=geospace/>{{sfn|Schrijver|Siscoe|2010|p=379}}

The variable space-weather conditions of geospace are affected by the behavior of the Sun and the solar wind; the subject of geospace is interlinked with [[heliophysics]]—the study of the Sun and its impact on the planets of the Solar System.{{sfn|Fichtner|Liu|2011|pp=341–345}} The day-side magnetopause is compressed by solar-wind pressure—the subsolar distance from the center of the Earth is typically 10 Earth radii. On the night side, the solar wind stretches the magnetosphere to form a [[magnetotail]] that sometimes extends out to more than 100–200 Earth radii.{{sfn|Koskinen|2010|pp=32, 42}}<ref name=HonesJr1986/> For roughly four days of each month, the lunar surface is shielded from the solar wind as the Moon passes through the magnetotail.{{sfn|Mendillo|2000|p=275}}

Geospace is populated by electrically charged particles at very low densities, the motions of which are controlled by the [[Earth's magnetic field]]. These plasmas form a medium from which storm-like disturbances powered by the solar wind can drive electrical currents into the Earth's upper atmosphere. [[Geomagnetic storm]]s can disturb two regions of geospace, the radiation belts and the ionosphere. These storms increase fluxes of energetic electrons that can permanently damage satellite electronics, interfering with shortwave radio communication and [[Global Positioning System|GPS]] location and timing.{{sfn|Goodman|2006|p=244}} Magnetic storms can be a hazard to astronauts, even in low Earth orbit. They create [[aurora (astronomy)|aurorae]] seen at high latitudes in an oval surrounding the [[geomagnetic pole]]s.<ref name=oecd/>

[[File:Artemis 1 at maximum distance from Earth.jpg|thumb|Earth and the Moon as seen from cislunar space on the 2022 [[Artemis 1]] mission]]
XGEO space is a concept used by the USA to refer to the space of high Earth orbits, with the 'X' being some multiple of [[geosynchronous orbit]] (GEO) at approximately {{convert|35786|km|mi|0|abbr=on}}.<ref name=sdc20150426/> Hence, the [[Lagrange point#Earth–Moon|L2 Earth-Moon Lagrange point]] at {{convert|448900|km|mi|0|abbr=on}} is approximately 10.67 XGEO.<ref name=Cunio_et_al_2021/> Translunar space is the region of lunar [[transfer orbit]]s, between the Moon and Earth.<ref name="NASA 2013"/> {{anchor|Cislunar space}}{{anchor|cislunar space}} '''Cislunar space''' is a region outside of Earth that includes [[lunar orbit]]s, the [[orbit of the Moon|Moon's orbital space around Earth]] and the Earth-Moon [[Lagrange point]]s.<ref name=sr2165/>

The region where a body's [[gravitational potential]] remains dominant against gravitational potentials from other bodies, is the body's [[Sphere of influence (astrodynamics)|sphere of influence]] or gravity well, mostly described with the [[Hill sphere]] model.<ref name=yoder1995/> In the case of Earth this includes all space from the Earth to a distance of roughly 1% of the mean distance from Earth to the Sun,{{sfn|Barbieri|2006|p=253}} or {{convert|1.5|e6km|e6mi|abbr=unit}}. Beyond Earth's Hill sphere extends along [[Earth's orbit]]al path its orbital and [[co-orbital]] space. This space is co-populated by groups of co-orbital [[Near-Earth Object]]s (NEOs), such as [[Horseshoe orbit|horseshoe librator]]s and [[Earth trojan]]s, with some NEOs at times becoming [[temporary satellite]]s and [[Quasi-satellite|quasi-moon]]s to Earth.<ref name=Granvik_et_al_2012/>

{{anchor|Deep space}}
'''Deep space''' is defined by the United States government as all of outer space which lies further from Earth than a typical low-Earth-orbit, thus assigning the Moon to deep-space.<ref name=USC_10101/> Other definitions vary the starting point of deep-space from, "That which lies beyond the orbit of the moon," to "That which lies beyond the farthest reaches of the Solar System itself."{{sfn|Dickson|2010|p=57}}{{sfn|Williamson|2006|p=97}}<ref name=Collins/> The [[ITU-R|International Telecommunication Union responsible for radio communication]], including with satellites, defines deep-space as, "distances from the Earth equal to, or greater than, {{convert|2|e6km|e6mi|abbr=unit}},"<ref name=ITU/> which is about five times the [[Lunar distance (astronomy)|Moon's orbital distance]], but which distance is also far less than the distance between Earth and any adjacent planet.<ref name=Williams_2021/>
[[File:Orbitalaltitudes.svg|center|700px|thumb|Near-Earth space showing the low-Earth (blue), medium Earth (green), and high Earth (red) orbits. The last extends beyond the radius of geosynchronous orbits]]