Using statistical analysis and computing, a duo of researchers at Western University in Canada has charted a path that likely pinpoints the origins of 67P/Churyumov-Gerasimenko, the target comet of ESA’s recent Rosetta mission.
Comet 67P/Churyumov-Gerasimenko likely spent millions of years in the scattering disk, a distant portion of the Kuiper belt. Image credit: Mattia Galiazzo / Paul Wiegert.
67P/Churyumov-Gerasimenko is dynamically a Jupiter-family comet. Its current orbit is very chaotic and it had recently a close encounter with Jupiter.
Western University researchers Dr. Mattia Galiazzo and Dr. Paul Wiegert think that the comet is relatively new to the inner parts of our Solar System, having only arrived about 10,000 years ago.
Prior to this time, the comet would have been inactive in frozen storage far from the Sun.
“During numerical simulations of its backward evolution 67/P is influenced by mean motion resonances with Jupiter, but also with Mars and Vesta, in particular with Ceres,” the authors explained.
“We performed a backward integration for 50 million years of 67/P (499 clones plus the nominal orbit) considering only gravitational forces from all the Solar System’s planets (apart from Mercury, whose mass was added to the Sun) plus gravitational perturbations of Vesta and Ceres.”
“We report on the locations of highest residence times of the clones and discuss the regions from which it is most likely to have originated from in the near- and long-term.”
The majority of Jupiter-family comets are thought to come from the Kuiper belt and the researchers believe, based on initial analysis of their investigation, that this is the case for 67P/Churyumov-Gerasimenko, as well.
Their analysis shows that, in transit, the comet likely spent millions of years in the scattering disk, a distant portion of the Kuiper belt, at about twice the distance of Neptune.
This distant origin for 67P/Churyumov-Gerasimenko implies it would be made from primordial material, meaning minerals that existed in their current form since before Earth was formed.
“These results come from computations of the comet’s orbit from the present to the past, which is computationally difficult due to the chaosity of the orbit caused by close encounters with Jupiter,” Dr. Galiazzo said.
“Thus the details are obscure but we can establish a dynamical pathway from its current orbit back to the Kuiper belt.”
The scientists presented their findings today at the joint 48th annual meeting of the Division for Planetary Sciences of the American Astronomical Society and 11th annual European Planetary Science Congress in Pasadena, California.
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Mattia Galiazzo & Paul Wiegert. 2016. On the origin of 67/P Churyumov-Gerasimenko. DPS48/EPSC11, abstract #116.13
