areostationary orbit

The radius of an areostationary orbit can be calculated using Kepler's Third Law.

$T^2\; =\; \backslash left(\{4\backslash pi^2\backslash over\{GM\}\}\backslash right)\; a^\{3\}$

Where:

Substituting the mass of Mars for M and the Martian sidereal day for T and solving for the semimajor axis yields a synchronous orbit radius of {{Convert|20428|km|mi|abbr=on}} above the surface of the Mars equator.Lodders, Katharina; Fegley, Bruce (1998). The Planetary Scientist's Companion. Oxford University Press. p. 190. {{ISBN|0-19-511694-1}}.{{Cite book |last1=Wertz |first1=James |title=Space Mission Engineering: The New SMAD |last2=Everett |first2=David |last3=Puschell |first3=Jeffery |publisher=Microcosm Press |year=2018 |isbn=978-1-881-883-15-9 |location=Torrance, California |pages=220}}{{Cite web |title=Stationkeeping in Mars orbit |url=http://www.planetary.org/blogs/emily-lakdawalla/2013/stationkeeping-in-mars-orbit.html |access-date=2017-11-21 |website=www.planetary.org |language=en}} Subtracting Mars's radius gives an orbital altitude of {{Convert|17032|km|mi|abbr=on}}.

Two stable longitudes exist - 17.92°W and 167.83°E. Satellites placed at any other longitude will tend to drift to these stable longitudes over time.

Several factors make placing a spacecraft into an areostationary orbit more difficult than a geostationary orbit. Since the areostationary orbit lies between Mars's two natural satellites, Phobos (semi-major axis: 9,376 km) and Deimos (semi-major axis: 23,463 km), any satellites in the orbit will suffer increased orbital station keeping costs due to unwanted orbital resonance effects. Mars's gravity is also much less spherical than earth due to uneven volcanism (i.e. Olympus Mons). This creates additional gravitational disturbances not present on earth, further destabilizing the orbit. Solar radiation pressure and sun-based perturbations are also present, as with an earth-based geostationary orbit. Actually placing a satellite into such an orbit is further complicated by the distance from earth and related challenges shared by any attempted Mars mission.{{Cite journal |last1=Silva |first1=Juan |last2=Romero |first2=Pilar |date=October 2013 |title=Optimal longitudes determination for the station keeping of areostationary satellites |url=https://www.sciencedirect.com/science/article/pii/S0032063313000044 |journal=Planetary and Space Science |volume=87 |pages=14–18 |bibcode=2013P&SS...87...14S |doi=10.1016/j.pss.2012.11.013 |issn=0032-0633 |access-date=30 December 2023 |via=Elsevier Science Direct}}{{Cite web |last=Lakdawalla |first=Emily |date=27 June 2013 |title=Stationkeeping in Mars orbit |url=https://www.planetary.org/articles/stationkeeping-in-mars-orbit |access-date=2023-12-31 |website=The Planetary Society |language=en}}

Satellites in an areostationary orbit would allow for greater amounts of data to be relayed back from the Martian surface easier than by using current methods. Satellites in the orbit would also be advantageous for monitoring Martian weather and mapping of the Martian surface.{{citation |last1=Montabone |first1=Luca |title=OBSERVING MARS FROM AREOSTATIONARY ORBIT BENEFITS AND APPLICATIONS |date=15 July 2020 |url=https://ntrs.nasa.gov/api/citations/20205005976/downloads/Areostationary%20White%20Paper%20-%20final%20version%20-%20amended%20head.pdf |journal=Planetary Science and Decadal Survey 2023-2032 |last2=Nicholas |first2=Heavens}}

In the early 2000s NASA explored the feasibility of placing communications satellites in an areocentric orbit as a part of the Mars Communication Network. In the concept, an areostationary relay satellite would transmit data from a network of landers and smaller satellites in lower Martian orbits back to earth.{{cite conference |last1=Bhasin |first1=Kul |author-link= |last2=Hayden |first2=Jeff |last3=Agre |first3=Jonathan |last4=Clare |first4=Loren |last5=Yan |first5=Tsun-Yee |date=September 2001 |year=2001 |title=Advanced Communication and Networking Technologies for Mars Exploration |trans-title= |url=https://ntrs.nasa.gov/api/citations/20010091011/downloads/20010091011.pdf |format= |conference=19th International Communications Satellite Systems Conference |language= |edition= |location= |publisher= |volume= |page= |pages= |at= |bibcode= |doi= |isbn= |oclc= |id= |archive-url= |archive-date= |access-date=10 January 2024 |quote= |conference-url= |editor= |book-title=}}{{Cite journal |last1=Hastrup |first1=R.C. |last2=Bell |first2=D.J. |last3=Cesarone |first3=R.J. |date=2003 |title=Mars network for enabling low-cost missions |url=|journal=Acta Astronautica |volume=52 |issue=2–6 |pages=227–235 |doi=10.1016/S0094-5765(02)00161-3 |bibcode=2003AcAau..52..227H }}

• Geostationary orbit
• Areosynchronous orbit
• List of orbits

{{reflist}}

• [https://web.archive.org/web/20071201030611/http://marsnet.jpl.nasa.gov/elements/marsats.html Mars Network - Marsats] - Historic NASA site devoted to proposed communications infrastructure for Mars exploration
• [http://www.lpi.usra.edu/meetings/robomars/pdf/6080.pdf Bandwidth available] from an areostationary satellite

{{orbits}}

Category:Mars orbits

Category:Astrodynamics