Ernst Messerschmid, Stefanos Fasoulas: Raumfahrtsysteme. Eine Einführung mit Übungen und Lösungen. Springer-Verlag, 2010, ISBN 978-3-642-12817-2, S.86ff. (books.google.com).
foreignpolicy.com
Michael Belfiore: The Rocketeer. In: foreignpolicy.com. Abgerufen am 21. September 2021 (amerikanisches Englisch).
Asif A. Siddiqi: Beyond Earth. A Chronicle of Deep Space Exploration, 1958–2016 (= The NASA history series). second Auflage. NASA History Program Office, Washington, D.C. 2018, ISBN 978-1-62683-042-4, SP2018-4041 (nasa.gov [PDF]).
Asif A. Siddiqi: Beyond Earth. A Chronicle of Deep Space Exploration, 1958–2016 (= The NASA history series). second Auflage. NASA History Program Office, Washington, D.C. 2018, ISBN 978-1-62683-042-4, SP2018-4041, S.1 (nasa.gov [PDF]).
Mariner 9: Details. National Space Science Data Center, abgerufen am 28. Dezember 2011.
redirecter.toolforge.org
Bizarre Lunar Orbits. In: science.nasa.gov. NASA, 6. November 2006, archiviert vom Original (nicht mehr online verfügbar) am 4. Dezember 2021; abgerufen am 9. Dezember 2012: „Lunar mascons make most low lunar orbits unstable … As a satellite passes 50 or 60 miles overhead, the mascons pull it forward, back, left, right, or down, the exact direction and magnitude of the tugging depends on the satellite’s trajectory. Absent any periodic boosts from onboard rockets to correct the orbit, most satellites released into low lunar orbits (under about 60 miles or 100 km) will eventually crash into the Moon. … [There are] a number of ‘frozen orbits’ where a spacecraft can stay in a low lunar orbit indefinitely. They occur at four inclinations: 27°, 50°, 76°, and 86° – the last one being nearly over the lunar poles. The orbit of the relatively long-lived Apollo 15 subsatellite PFS-1 had an inclination of 28°, which turned out to be close to the inclination of one of the frozen orbits – but poor PFS-2 was cursed with an inclination of only 11°.“
Bizarre Lunar Orbits. In: science.nasa.gov. NASA, 6. November 2006, archiviert vom Original (nicht mehr online verfügbar) am 4. Dezember 2021; abgerufen am 9. Dezember 2012: „Lunar mascons make most low lunar orbits unstable … As a satellite passes 50 or 60 miles overhead, the mascons pull it forward, back, left, right, or down, the exact direction and magnitude of the tugging depends on the satellite’s trajectory. Absent any periodic boosts from onboard rockets to correct the orbit, most satellites released into low lunar orbits (under about 60 miles or 100 km) will eventually crash into the Moon. … [There are] a number of ‘frozen orbits’ where a spacecraft can stay in a low lunar orbit indefinitely. They occur at four inclinations: 27°, 50°, 76°, and 86° – the last one being nearly over the lunar poles. The orbit of the relatively long-lived Apollo 15 subsatellite PFS-1 had an inclination of 28°, which turned out to be close to the inclination of one of the frozen orbits – but poor PFS-2 was cursed with an inclination of only 11°.“
