The Mysteries of Triton’s Origin

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There are many mysteries in our Solar System, let alone our galaxy and the Universe. One mystery in our Solar System is Triton’s retrograde orbit. For starters, what does “retrograde” mean? Simply, put Triton orbits Neptune in a manner opposite that of most other moons in the solar system.

Fun Fact: In the distant future, Triton is expected to cross Neptune’s “roche limit” and break up. Many other moons in our solar system have retrograde orbits, which are speculated to be the result of an object passing close enough to the host planet for its gravity to “capture” said object.

What makes Triton special is that many scientists believe Triton to be a captured Kuiper Belt Object, similar to Pluto. As a matter of fact, Triton is larger than Pluto! The issue with this theory is that we haven’t studied Kuiper Belt Objects in any real detail! Luckily, the NASA New Horizons mission is expected to perform a fly-by of Pluto in 2015, so we’ll have at least some data on these frozen bodies in the outer Solar System.

KFC over at The Physics arXiv Blog wrote a blog post concerning a proposed mission to study Triton and the Kuiper Belt. In the blog post KFC writes:

So Bruno Christophe at ONERA – The French Aerospace Lab in Chatillon and a few amis want to go and have a look. Their plan is to send a spacecraft to fly past Neptune, take a good look at Triton, and then fly on to find a Kuiper Belt object to study. If they look remotely similar, then that’ll back up the idea that Triton really is from the Kuiper Belt. That’s not a bad problem to solve in a single mission (although the choice of Kuiper Belt object will obviously be crucial)..

The team also proposed to study the effects of gravity at long distances, with hopes to further explain the “Pioneer Anomaly”, despite some evidence that the anomaly may be due to uneven thermal properties of the Pioneer probes.

KFC adds,

That’s an ambitious medium sized mission (about 500 kg). Christophe and co proposed their Outer Solar System Mission to ESA last year in the hope that it would also attract funding from NASA and launch in the 2020 timeframe. Sadly it seems to have missed the cut this time. ESA announced its medium-sized mission candidates in February and OSS wasn’t in it…

With New Horizons currently on its way to Pluto and the Kuiper belt, it’s understandable that the ESA would have a difficult time justifying the Outer Solar System Mission as proposed by Christophe and his colleagues.

You can read more about the proposal via arXiv.org at: http://arxiv.org/abs/1106.0132

Source:The Physics arXiv Blog (Used with permission)

Ray Sanders is a Sci-Fi geek, astronomer and blogger. Currently researching variable stars at Arizona State University, he writes for Universe Today, The Planetary Society blog, and his own blog, Dear Astronomer