Discovery of huge trans-Neptunian object (maybe a comet) 2006 SQ372 announced
Wednesday, August 20, 2008
This is another weird object that has been recently discovered, an object some 100 km in diameter, perhaps a comet, that has an extremely eccentric orbit that takes between 22000 and 32000 years to complete, and may be from the inner Oort Cloud, or maybe not:
Their discoverers hypothesize that the object could come from the inner Oort cloud, however other scientist like California Institute of Technology's Mike Brown also consider other possibilities, as "it may have formed from debris just beyond Neptune [in the Kuiper belt] and been 'kicked' into it's distant orbit by a planet like Neptune or Uranus".The Wikipedia article on a similar object, (148209) 2000 CR105, goes over a few possibilities for how these objects might have acquired these orbits:
Several hypotheses have been put forward:The Wikipedia page on the Oort Cloud also lists these three objects (including Sedna) side by side:
- They were pulled from their original positions by a passing star.
- They were pulled from their original positions by a very distant and as-yet-undiscovered (albeit unlikely) giant planet.
- They were pulled from their original positions by an as-yet-undiscovered companion star orbiting the Sun. (See: Nemesis (star))
- They were captured from another planetary system during a close encounter early in the Sun's history. According to Kenyon and Bromley, there is a 15% probability that a star like the Sun had an early close encounter, and a 1% probability that outer planetary exchanges would have happened. 2000 CR105 is 2–3 times more likely to be a captured planetary object than Sedna.
Number | Name | Equatorial diameter (km) | Perihelion (AU) | Aphelion (AU) | Diameter method |
---|---|---|---|---|---|
90377 | Sedna | 1,180–1,800 km | 76.1 | 892 | thermal |
148209 | 2000 CR105 | ~250 km | 44.3 | 397 | assumed |
- | 2006 SQ372 | 50–100 km | 24 | 2,010 | assumed |
I like the idea of the Oort Cloud and how it hypothetically should spread out to a full light-year away from the Sun; the more there is to see between us and the next star system the better. I'd always thought before the discovery of all these objects that a Solar System ending at Pluto and then turning into pure nothingness for the next 4.3 LY was kind of boring.
Here's an article on the discovery, and the Wikipedia article on the Sloan Digital Sky Survey.
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