http://www.sciencedaily.com/releases/2009/09/090914111825.htmFigure showing comet Kushida-Muramatsu's orbital path around Jupiter. (Credit: Ohtsuka/Asher)
ScienceDaily (Sep. 15, 2009) — Comet 147P/Kushida-Muramatsu was captured as a temporary moon of Jupiter in the mid-20th century and remained trapped in an irregular orbit for about twelve years.
There are only a handful of known comets where this phenomenon of temporary satellite capture has occurred and the capture duration in the case of Kushida-Muramatsu, which orbited Jupiter between 1949 and 1961, is the third longest.
The discovery will be presented at the European Planetary Science Congress in Potsdam by Dr David Asher on Monday 14 September.
An international team led by Dr Katsuhito Ohtsuka modelled the trajectories of 18 “quasi-Hilda comets," objects with the potential to go through a temporary satellite capture by Jupiter that results in them either leaving or joining the “Hilda” group of objects in the asteroid belt. Most of the cases of temporary capture were flybys, where the comets did not complete a full orbit. However, Dr Ohtsuka’s team used recent observations tracking Kushida-Muramatsu over nine years to calculate hundreds of possible orbital paths for the comet over the previous century. In all scenarios, Kushida-Muramatsu completed two full revolutions of Jupiter, making it only the fifth captured orbiter to be identified.
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