Satellite system (astronomy): Difference between revisions
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==Natural formation and evolution== |
==Natural formation and evolution== |
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| ⚫ | Satellite systems, like planetary systems, are the product of gravitational attraction, but are also sustained through [[fictitious force]]s. While the general consensus is that most planetary systems are formed from an accretionary disks, the formation of satellite systems is less clear. The origin of many moons are investigated on a case by case basis, and the larger systems are thought to have formed through a combination of one or more processes. |
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| ⚫ | |||
| ⚫ | Satellite systems, like planetary systems, are the product of gravitational attraction, but are also sustained through [[fictitious force]]s. While the general consensus is that most planetary systems are formed from an accretionary disks, the formation of satellite systems is less clear. The origin of many moons are investigated on a case by case basis, and the larger systems are thought to have formed through a combination of one or more |
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* Accretion disks around giant planets may occur in a similar to the formation of planets around stars (this is one of the theories for the formations of the satellite systems of Uranus and Saturn, for example) |
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| ⚫ | |||
* Collision, including [[Giant impact]] (such as the formation of Earth's system and possibly Pluto's. It is thought that early Earth had multiple moons resulting from such impacts. This is also a prevailing theory for the origin of the Moons of Mars.) |
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* Capture (some theories suggest this is the origin of Neptune's major moon Triton, the moons of Mars, and Saturn's moon [[Phoebe (moon)|Phoebe]]) |
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* Artificial (some controversial early theories, for example [[Spaceship Moon Theory]] and Shklovsky's "Hollow Phobos" hypothesis have suggested that moons were not formed naturally at all) |
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===System Stability=== |
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[[File:L4 diagram.svg|thumb|right|200px|Gravitational accelerations at {{L4|nolink=yes}}]] |
[[File:L4 diagram.svg|thumb|right|200px|Gravitational accelerations at {{L4|nolink=yes}}]] |
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Satellites are stable at the {{L4|nolink=yes}} and {{L5|nolink=yes}} Lagrangian points. These lie at the third corners of the two [[equilateral triangle]]s in the plane of orbit whose common base is the line between the centers of the two masses, such that the point lies behind ({{L5|nolink=yes}}) or ahead ({{L4|nolink=yes}}) of the smaller mass with regard to its orbit around the larger mass. The triangular points ({{L4|nolink=yes}} and {{L5|nolink=yes}}) are stable equilibria, provided that the ratio of M<sub>1</sub>/M<sub>2</sub> is greater than 24.96.<ref group="note"><big>Actually <math>\tfrac{25+\sqrt{621}}{2}</math></big> ≈ 24.9599357944 </ref><ref name="cornish">{{PDFlink|''[http://wmap.gsfc.nasa.gov/media/ContentMedia/lagrange.pdf The Lagrange Points]''}}, Neil J. Cornish with input from Jeremy Goodman</ref> When a body at these points is perturbed, it moves away from the point, but the factor opposite of that which is increased or decreased by the perturbation (either gravity or angular momentum-induced speed) will also increase or decrease, bending the object's path into a stable, [[Common bean#Red or kidney beans|kidney-bean]]-shaped orbit around the point (as seen in the corotating frame of reference). |
Satellites are stable at the {{L4|nolink=yes}} and {{L5|nolink=yes}} Lagrangian points. These lie at the third corners of the two [[equilateral triangle]]s in the plane of orbit whose common base is the line between the centers of the two masses, such that the point lies behind ({{L5|nolink=yes}}) or ahead ({{L4|nolink=yes}}) of the smaller mass with regard to its orbit around the larger mass. The triangular points ({{L4|nolink=yes}} and {{L5|nolink=yes}}) are stable equilibria, provided that the ratio of M<sub>1</sub>/M<sub>2</sub> is greater than 24.96.<ref group="note"><big>Actually <math>\tfrac{25+\sqrt{621}}{2}</math></big> ≈ 24.9599357944 </ref><ref name="cornish">{{PDFlink|''[http://wmap.gsfc.nasa.gov/media/ContentMedia/lagrange.pdf The Lagrange Points]''}}, Neil J. Cornish with input from Jeremy Goodman</ref> When a body at these points is perturbed, it moves away from the point, but the factor opposite of that which is increased or decreased by the perturbation (either gravity or angular momentum-induced speed) will also increase or decrease, bending the object's path into a stable, [[Common bean#Red or kidney beans|kidney-bean]]-shaped orbit around the point (as seen in the corotating frame of reference). |
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=== |
===Accretion theories=== |
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Accretion disks around giant planets may occur in a similar to the formation of planets around stars (this is one of the theories for the formations of the satellite systems of Uranus<ref name="Mousis 2004">{{cite doi | 10.1051/0004-6361:20031515 }}</ref> and Saturn, for example). Accretion is also proposed by some as a theory for the origin of the Earth-Moon system<ref name="burro.cwru.edu">http://burro.cwru.edu/Academics/Astr221/SolarSys/lunaform.html</ref>, however the angular momentum of system and the Moon's smaller iron core can not easily be explained by this.<ref name="burro.cwru.edu"/> |
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====Debris disks==== |
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| ⚫ | Another proposed mechanism for satellite system formation is accretion from debris. Scientists theorise that the Galilean moons are thought by some to be a more recent generation of moons formed from the disintegration of earlier generations of accreted moons. Ring systems are also thought to be the result of satellites disintegrated near the [[Roche limit]]. Such disks could, over time, coalesce to form natural satellites. |
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===Collision theories=== |
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{{main|Giant impact hypothesis}} |
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[[File:Creation of the moons of Pluto.jpg|thumb|Formation of Pluto's moons. 1: a [[Kuiper belt object]] nears [[Pluto]]; 2: the KBO impacts Pluto; 3: a [[dust ring]] forms around Pluto; 4: the [[debris]] aggregates to form Charon; 5: Pluto and [[Charon (moon)|Charon]] relax into spherical bodies.]] |
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Collision is one of the leading theories for the formation of satellite systems, particularly those of the Earth and Pluto. Computer simulations have been used to demonstrate that [[Giant impact]]s could have been the [[Origin of the Moon]]. It is thought that early Earth had multiple moons resulting from the giant impact. Similar models have been used to explain the creation of the Pluto system. This is also a prevailing theory for the origin of the Moons of Mars.<ref name = "Giuranna">{{Cite conference |
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| first = M. | last = Giuranna | authorlink = |display-authors=4 |
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|author2=Roush, T. L. |author3=Duxbury, T. |author4=Hogan, R. C. |author5=Geminale, A. |author6= Formisano |
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| title = Compositional Interpretation of PFS/MEx and TES/MGS Thermal Infrared Spectra of Phobos |
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| booktitle = European Planetary Science Congress Abstracts, Vol. 5 |
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| pages = | publisher = | date = 2010 | location = | url = http://meetingorganizer.copernicus.org/EPSC2010/EPSC2010-211.pdf |
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| doi = | id = | accessdate = 1 October 2010}}</ref> Both sets of findings support an origin of Phobos from material ejected by an impact on Mars that reaccreted in Martian orbit,<ref name = "Blast">{{Cite web | title = Mars Moon Phobos Likely Forged by Catastrophic Blast |
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| work = [http://www.space.com/ Space.com web site] | publisher = | date = 27 September 2010 |
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| url = http://www.space.com/scienceastronomy/martian-moon-forged-by-catastrophic-blast-100927.html |
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| accessdate = 1 October 2010}}</ref> Collision is also used to explain perculiarities in the Uranus system.<ref>{{cite book|title=Atlas of Uranus|first=Garry E. |last=Hunt |author2=Patrick Moore|publisher=Cambridge University Press|date=1989|isbn=0-521-34323-2|pages=78–85 |
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}} |
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</ref> |
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===Gravitational Capture theories=== |
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| ⚫ | |||
Some theories suggest that gravitational capture is the origin of Neptune's major moon Triton,<ref name="Agnor06"> |
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{{cite doi |10.1038/nature04792}}</ref> the moons of Mars,<ref>[http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020038729.pdf "Origin of Martian Moons from Binary Asteroid Dissociation"], AAAS - 57725, American Association for Advancement of Science Annual Meeting 2002</ref> and Saturn's moon [[Phoebe (moon)|Phoebe]].<ref>{{cite journal |last=Johnson |first=Torrence V. |last2=Lunine |first2=Jonathan I. |title=Saturn's moon Phoebe as a captured body from the outer Solar System |journal=[[Nature (journal)|Nature]] |volume=435 |issue=7038 |pages=69–71 |doi=10.1038/nature03384 |date=2005 |bibcode=2005Natur.435...69J |pmid=15875015 }}</ref><ref>{{cite web |last=Martinez |first=C. |url=http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=568 |title=Scientists Discover Pluto Kin Is a Member of Saturn Family |work=Cassini–Huygens News Releases |date=May 6, 2005 }}</ref> Some scientist have put forward extended atmospheres around young planets as a mechanism for slowing the movement of a passing objects to aid in capture. The hypothesis has been put forward to explain the irregular satellite orbits of [[Jupiter]] and [[Saturn]], for example<ref>{{Citation |
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| title = Irregular Satellites of the Planets: Products of Capture in the Early Solar System |
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| date = 2007 |
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| journal = Annual Review of Astronomy and Astrophysics |
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| pages = 261–295 |
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| volume = 45 |
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| doi = 10.1146/annurev.astro.44.051905.092459 |
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| last1 = Jewitt | first1 = David |
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| last2 = Haghighipour | first2 = Nader |arxiv = astro-ph/0703059 |bibcode = 2007ARA&A..45..261J }}</ref> and even by some for Earth's Moon. In the case of the latter, however, virtually identical [[isotope]] ratios found in samples of the the Earth and Moon cannot be explained easily in this theory difficult.<ref name=wiechert>{{Cite journal | unused_data=title=Oxygen Isotopes and the Moon-Forming Giant Impact | title=Science | author=Wiechert, U. | author2=Halliday, A. N. | author3=Lee, D.-C. | author4=Snyder, G. A. | author5=Taylor, L. A. | author6=Rumble, D. | volume=294 | issue=12 | pages=345–348 |date=October 2001| doi=10.1126/science.1063037 | url=http://www.sciencemag.org/cgi/content/abstract/294/5541/345 | accessdate=2009-07-05 | publisher=[[Science (journal)]] | pmid=11598294 | journal=Science |bibcode = 2001Sci...294..345W }}</ref> |
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====Temporary Capture==== |
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Evidence for the natural process of satellite capture has been found in direct observation of objects captured by Jupiter. Five such captures have been observed, the longest being for approximately twelve years. Based on computer modelling, the future capture of comet [[111P/Helin-Roman-Crockett]] for 18 years is predicted to begin in 2068.<ref name="Ohtsukaetal2008">{{cite journal |
Evidence for the natural process of satellite capture has been found in direct observation of objects captured by Jupiter. Five such captures have been observed, the longest being for approximately twelve years. Based on computer modelling, the future capture of comet [[111P/Helin-Roman-Crockett]] for 18 years is predicted to begin in 2068.<ref name="Ohtsukaetal2008">{{cite journal |
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| bibcode = 2008A&A...489.1355O |
| bibcode = 2008A&A...489.1355O |
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| accessdate = 14 September 2009 |
| accessdate = 14 September 2009 |
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|archiveurl=http://www.webcitation.org/5jrTZHLsI|archivedate=2009-09-17|deadurl=no}}</ref> However temporary captured orbits have highly irregular and unstable, the theorised processes behind stable capture may be exceptionally rare. |
|archiveurl=http://www.webcitation.org/5jrTZHLsI|archivedate=2009-09-17|deadurl=no}}</ref> However temporary captured orbits have highly irregular and unstable, the theorised processes behind stable capture may be exceptionally rare. |
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===Controversial theories=== |
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Some controversial early theories, for example [[Spaceship Moon Theory]] and Shklovsky's "Hollow Phobos" hypothesis have suggested that moons were not formed naturally at all. These theories tend to fail [[Occam's razor]]. While artificial satellites are now a common occurrence in the Solar System, the largest, the [[International Space Station]] is 108.5 metres at its widest, is tiny compared to the several kilometres of the smallest natural satellites. |
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==Notable Satellite systems== |
==Notable Satellite systems== |
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Revision as of 11:20, 18 April 2015
A satellite system is a set of gravitationally bound objects in orbit around a planetary mass object or minor planet. Generally speaking, it is a set of natural satellites (moons), although such systems may also consist of bodies such as moonlets, ring systems, minor-planet moons and artificial satellites any of which may themselves have satellite systems of their own. Some satellite systems have complex interactions with both their parent and other moons, including magnetic, tidal, atmospheric and orbital interactions such as orbital resonances and libration. Individually major satellite objects are designated in Roman numerals. Where only one satellite is known, the system is referred to using the hyphenated names of the primary and its satellite (e.g. the "Earth-Moon system").
Many Solar System objects are known to possess satellite systems, though their origin is still unclear. Notable examples include the Moons of Jupiter (including the large Galilean moons) and Moons of Saturn (with its ring system), which are large and diverse. Giant planets of the Solar System possess large satellite systems as well as planetary rings, and it is inferred that this is a general pattern. Several objects farther from the Sun also have satellite systems consisting of multiple moons, including the complex Pluto system where multiple objects orbit a common center of mass, as well as many asteroids and plutinos. Apart from the Earth-Moon system and Mars' system of two tiny natural satellites, the other terrestrial planets are generally not considered satellite systems, although some have been orbited by artificial satellites originating from Earth.
Little is known of satellite systems beyond the Solar System, although it is inferred that natural satellites are common. J1407 is an example of an extrasolar satellite system.[1] It is also theorised that Rogue planets ejected from their planetary system could retain a system of satellites.[2]
Natural formation and evolution
Satellite systems, like planetary systems, are the product of gravitational attraction, but are also sustained through fictitious forces. While the general consensus is that most planetary systems are formed from an accretionary disks, the formation of satellite systems is less clear. The origin of many moons are investigated on a case by case basis, and the larger systems are thought to have formed through a combination of one or more processes.
System Stability
Satellites are stable at the L4 and L5 Lagrangian points. These lie at the third corners of the two equilateral triangles in the plane of orbit whose common base is the line between the centers of the two masses, such that the point lies behind (L5) or ahead (L4) of the smaller mass with regard to its orbit around the larger mass. The triangular points (L4 and L5) are stable equilibria, provided that the ratio of M1/M2 is greater than 24.96.[note 1][3] When a body at these points is perturbed, it moves away from the point, but the factor opposite of that which is increased or decreased by the perturbation (either gravity or angular momentum-induced speed) will also increase or decrease, bending the object's path into a stable, kidney-bean-shaped orbit around the point (as seen in the corotating frame of reference).
Accretion theories
Accretion disks around giant planets may occur in a similar to the formation of planets around stars (this is one of the theories for the formations of the satellite systems of Uranus[4] and Saturn, for example). Accretion is also proposed by some as a theory for the origin of the Earth-Moon system[5], however the angular momentum of system and the Moon's smaller iron core can not easily be explained by this.[5]
Debris disks
Another proposed mechanism for satellite system formation is accretion from debris. Scientists theorise that the Galilean moons are thought by some to be a more recent generation of moons formed from the disintegration of earlier generations of accreted moons. Ring systems are also thought to be the result of satellites disintegrated near the Roche limit. Such disks could, over time, coalesce to form natural satellites.
Collision theories
Collision is one of the leading theories for the formation of satellite systems, particularly those of the Earth and Pluto. Computer simulations have been used to demonstrate that Giant impacts could have been the Origin of the Moon. It is thought that early Earth had multiple moons resulting from the giant impact. Similar models have been used to explain the creation of the Pluto system. This is also a prevailing theory for the origin of the Moons of Mars.[6] Both sets of findings support an origin of Phobos from material ejected by an impact on Mars that reaccreted in Martian orbit,[7] Collision is also used to explain perculiarities in the Uranus system.[8]
Gravitational Capture theories
Some theories suggest that gravitational capture is the origin of Neptune's major moon Triton,[9] the moons of Mars,[10] and Saturn's moon Phoebe.[11][12] Some scientist have put forward extended atmospheres around young planets as a mechanism for slowing the movement of a passing objects to aid in capture. The hypothesis has been put forward to explain the irregular satellite orbits of Jupiter and Saturn, for example[13] and even by some for Earth's Moon. In the case of the latter, however, virtually identical isotope ratios found in samples of the the Earth and Moon cannot be explained easily in this theory difficult.[14]
Temporary Capture
Evidence for the natural process of satellite capture has been found in direct observation of objects captured by Jupiter. Five such captures have been observed, the longest being for approximately twelve years. Based on computer modelling, the future capture of comet 111P/Helin-Roman-Crockett for 18 years is predicted to begin in 2068.[15][16] However temporary captured orbits have highly irregular and unstable, the theorised processes behind stable capture may be exceptionally rare.
Controversial theories
Some controversial early theories, for example Spaceship Moon Theory and Shklovsky's "Hollow Phobos" hypothesis have suggested that moons were not formed naturally at all. These theories tend to fail Occam's razor. While artificial satellites are now a common occurrence in the Solar System, the largest, the International Space Station is 108.5 metres at its widest, is tiny compared to the several kilometres of the smallest natural satellites.
Notable Satellite systems
Known satellite systems consisting of multiple object or around planetary mass objects in order of orbit from the Sun:
| Object | Class | Natural Satellites | Artificial Satellites | Note |
| Mercury | Planet | 1* | *MESSENGER, up until May 2015 | |
| Venus | Planet | * | *Venus Express was a satellite until January, 2015 | |
| Earth | Planet | 1 | 2,465* | *Includes oribiting space stations |
| The Moon | Natural satellite | 10* | *Includes several derelict | |
| (136617) 1994 CC | near-Earth asteroid | 2 | ||
| (153591) 2001 SN263 | near-Earth asteroid | 2 | ||
| (285263) 1998 QE2 | near-Earth asteroid | 1 | ||
| 67P/Churyumov–Gerasimenko | Comet | 1* | *Rosetta, since August 2014 | |
| Mars | Planet | 2 | 11* | *6 of these are derelict. See also Moons of Mars |
| Ceres | Dwarf planet | 1* | *Dawn | |
| 87 Sylvia | Main-belt Asteroid | 2 | ||
| 3749 Balam | Main-belt Asteroid | 2 | ||
| 45 Eugenia | Main-belt Asteroid | 2 | ||
| 93 Minerva | Main-belt Asteroid | 2 | ||
| 130 Elektra | Main-belt Asteroid | 2 | ||
| 216 Kleopatra | Main-belt Asteroid | 2 | ||
| Jupiter | Planet | 67 | * | With ring system and four large Galilean moons. *Juno is expected in 2016. See also Moons of Jupiter |
| Saturn | Planet | 62 | 1 | Large ring system. *Cassini–Huygens probe orbiting since 2014. See also Moons of Saturn |
| 10199 Chariklo | Centaur | First minor planet known to possess a ring system | ||
| Uranus | Planet | 27 | With ring system. See also Moons of Uranus | |
| Neptune | Planet | 14 | With ring system. See also Moons of Neptune | |
| Pluto | Dwarf planet | 5 | See also Moons of Pluto | |
| Eris | Dwarf planet | 1 | Dysnomia | |
| Haumea | Dwarf planet | 2 | see also Moons of Haumea | |
| Orcus | Kuiper belt object | 1 | ||
| Quaoar | Kuiper belt object | 1 | Weywot | |
| 1998 WW31 | Kuiper belt object | 1 | ||
| (48639) 1995 TL8 | Kuiper belt object | 1 |
Complex interactions
Natural satellite systems, particularly those involving multiple planetary mass objects can have complex interactions which can have effects on multiple bodies or across the wider system.
Orbital
Orbital resonances are present in several satellite systems:
- 2:4 Tethys–Mimas (Saturn’s moons)
- 1:2 Dione–Enceladus (Saturn’s moons)
- 3:4 Hyperion–Titan (Saturn's moons)
- 1:2:4 Ganymede–Europa–Io (Jupiter’s moons)
Other possible orbital interactions include libration and co-orbital configuration. The Saturnian moons Janus and Epimetheus share their orbits, the difference in semi-major axes being less than either's mean diameter. Libration is a perceived oscillating motion of orbiting bodies relative to each other. The Earth-moon satellite system is known to produce this effect.
Gas
Some satellite systems have been known to have gas interactions between objects. Notable examples include the Jupiter and Saturn systems. The Io plasma torus is a transfer of oxygen and sulfur from the tenuous atmosphere of Jupiter's volcanic moon, Io and other objects including Jupiter and Europa. A torus of oxygen and hydrogen produced by Saturn's moon, Enceladus forms part of the E ring around Saturn. Similar tori produced by Saturn's moon Titan (nitrogen) and Neptune's moon Triton (hydrogen) is predicted.
Magnetic
Complex magnetic interactions have been observed in satellite systems. Most notably, the interaction of Jupiter's strong magnetic field with those of Ganymede and Io. Observations suggest that such interactions can cause the stripping of atmospheres from moons and the generation of spectacular auroras.
Tidal
Tidal energy including tidal acceleration can have effects on both the primary and satellites. The Moon's tidal forces deform the Earth and hydrosphere, similarly heat generated from tidal friction on the moons of other planets is found to be responsible for their geologically active features.
Tidal interactions also cause orbits, which is already closer to change. For instance, Triton's orbit around Neptune is decaying and 3.6 billion years from now, it is predicted that this will cause Triton to pass within Neptune's Roche limit[17] resulting in either a collision with Neptune's atmosphere or the breakup of Triton, forming a large ring similar to that found around Saturn.[17]
Zones and habitability
Based on tidal heating models, scientists have defined zones in satellite systems similarly to those of planetary systems. One such zone is the circumplanetary habitable zone (or "habitable edge"). According to this theory, moons closer to their planet than the habitable edge cannot support liquid water at their surface. When effects of eclipses as well as constraints from a satellite's orbital stability are included into this concept, one finds that — depending on a moon's orbital eccentricity — there is a minimum mass of roughly 0.2 solar masses for stars to host habitable moons within the stellar HZ.[18]
The magnetic environment of exomoons, which is critically triggered by the intrinsic magnetic field of the host planet, has been identified as another effect on exomoon habitability.[19] Most notably, it was found that moons at distances between about 5 and 20 planetary radii from a giant planet can be habitable from an illumination and tidal heating point of view, but still the planetary magnetosphere would critically influence their habitability.
Notes
- ^ Actually ≈ 24.9599357944
References
- ^ Matthew A. Kenworthy, Eric E. Mamajek (2015-01-22). "Modeling giant extrasolar ring systems in eclipse and the case of J1407b: sculpting by exomoons?". Retrieved 2015-01-27. (arXiv:1501.05652)
- ^ The Survival Rate of Ejected Terrestrial Planets with Moons by J. H. Debes, S. Sigurdsson
- ^ Template:PDFlink, Neil J. Cornish with input from Jeremy Goodman
- ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi: 10.1051/0004-6361:20031515 , please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi= 10.1051/0004-6361:20031515instead. - ^ a b http://burro.cwru.edu/Academics/Astr221/SolarSys/lunaform.html
- ^ Giuranna, M.; Roush, T. L.; Duxbury, T.; Hogan, R. C.; et al. (2010). "Compositional Interpretation of PFS/MEx and TES/MGS Thermal Infrared Spectra of Phobos" (PDF). European Planetary Science Congress Abstracts, Vol. 5. Retrieved 1 October 2010.
{{cite conference}}: Unknown parameter|booktitle=ignored (|book-title=suggested) (help) - ^ "Mars Moon Phobos Likely Forged by Catastrophic Blast". Space.com web site. 27 September 2010. Retrieved 1 October 2010.
{{cite web}}: External link in|work= - ^ Hunt, Garry E.; Patrick Moore (1989). Atlas of Uranus. Cambridge University Press. pp. 78–85. ISBN 0-521-34323-2.
- ^
Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1038/nature04792, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1038/nature04792instead. - ^ "Origin of Martian Moons from Binary Asteroid Dissociation", AAAS - 57725, American Association for Advancement of Science Annual Meeting 2002
- ^ Johnson, Torrence V.; Lunine, Jonathan I. (2005). "Saturn's moon Phoebe as a captured body from the outer Solar System". Nature. 435 (7038): 69–71. Bibcode:2005Natur.435...69J. doi:10.1038/nature03384. PMID 15875015.
- ^ Martinez, C. (May 6, 2005). "Scientists Discover Pluto Kin Is a Member of Saturn Family". Cassini–Huygens News Releases.
- ^ Jewitt, David; Haghighipour, Nader (2007), "Irregular Satellites of the Planets: Products of Capture in the Early Solar System", Annual Review of Astronomy and Astrophysics, 45: 261–295, arXiv:astro-ph/0703059, Bibcode:2007ARA&A..45..261J, doi:10.1146/annurev.astro.44.051905.092459
- ^ Wiechert, U.; Halliday, A. N.; Lee, D.-C.; Snyder, G. A.; Taylor, L. A.; Rumble, D. (October 2001). "Science". Science. 294 (12). Science (journal): 345–348. Bibcode:2001Sci...294..345W. doi:10.1126/science.1063037. PMID 11598294. Retrieved 2009-07-05.
{{cite journal}}: Unknown parameter|unused_data=ignored (help) - ^ Ohtsuka, Katsuhito; Yoshikawa, M.; Asher, D. J.; Arakida, H.; Arakida, H. (October 2008). "Quasi-Hilda comet 147P/Kushida-Muramatsu. Another long temporary satellite capture by Jupiter". Astronomy and Astrophysics. 489 (3): 1355–1362. arXiv:0808.2277. Bibcode:2008A&A...489.1355O. doi:10.1051/0004-6361:200810321.
- ^ Kerensa McElroy (14 September 2009). "Captured comet becomes moon of Jupiter". Cosmos Online. Archived from the original on 2009-09-17. Retrieved 14 September 2009.
{{cite web}}: Unknown parameter|deadurl=ignored (|url-status=suggested) (help) - ^ a b Chyba, C. F.; Jankowski, D. G.; Nicholson, P. D. (July 1989). "Tidal evolution in the Neptune-Triton system". Astronomy and Astrophysics. 219 (1–2): L23–L26. Bibcode:1989A&A...219L..23C.
- ^ Heller, René (September 2012). "Exomoon habitability constrained by energy flux and orbital stability". Astronomy and Astrophysics. 545: L8. arXiv:1209.0050. Bibcode:2012A&A...545L...8H. doi:10.1051/0004-6361/201220003.
- ^ Heller, René (September 2013). "Magnetic shielding of exomoons beyond the circumplanetary habitable edge". The Astrophysical Journal Letters. arXiv:1309.0811. Bibcode:2013ApJ...776L..33H. doi:10.1088/2041-8205/776/2/L33.