View Full Version : The largest Kuiper belt objects

2006-May-27, 06:24 PM
Title: The largest Kuiper belt objects

The past year has seen an explosion in the discoveries of Pluto-sized objects in the Kuiper belt. With the discoveries of the methane-covered 2003 UB313 and 2005 FY9, the multiple satellite system of 2003 EL61, and the Pluto-Charon analogy system of Orcus and its satellite, it is finally apparent that Pluto is not a unique oddball at the edge of the solar system, but rather one of a family of similarly large objects in the Kuiper belt and beyond.

Read more (http://www.stsci.edu/observing/phase2-public/10860.pdf) (PDF)

90482 Orcus (originally known by the provisional designation 2004 DW) is a Kuiper Belt object (KBO) that was discovered by Michael Brown of Caltech, Chad Trujillo of the Gemini Observatory, and David Rabinowitz of Yale University. The discovery images of this object were acquired on February 17, 2004. Precovery images as early as November 8, 1951 were later identified.

Read more (http://en.wikipedia.org/wiki/90482_Orcus)

Kullat Nunu
2006-May-28, 06:36 PM
This is an interesting discovery and hopefully will be announced as soon as possible. Hopefully the Hubble measurements will also nail down the diameter of Orcus and 2005 FY9. Same document reveals also that another very large Kuiper Belt object, 2002 UX25, has a satellite.

2006-May-29, 10:50 AM
Are Kuiper moons more common than asteroid moons?

2006-May-29, 11:43 AM
About 11% of transneptunian objects are binaries (though it may be because we have found only the biggest with better chance of capturing or creating a moon), and one study has put a figure of 16% of near Earth asteroids that are binary (though these pairs may have been created by the tidal effects of Earth's gravity. The asteroids are disrupted when they make close approaches to the planet.).

Read more (http://www.johnstonsarchive.net/astro/astmoontable.html)

It must be remembered that the first asteroid moon to be identified was Dactyl which orbits 243 Ida. It was discovered by the Galileo probe only in 1993.


Title: Discovery of a Binary Centaur
Authors: K. S. Noll, H. F. Levison, W. M. Grundy, D. C. Stephens

Researchers have identified a binary companion to (42355) 2002 CR46 in their ongoing deep survey using the Hubble Space Telescope's High Resolution Camera.
It is the first companion to be found around an object in a non-resonant orbit that crosses the orbits of giant planets. Objects in orbits of this kind, the Centaurs, have experienced repeated strong scattering with one or more giant planets and therefore the survival of binaries in this transient population has been in question.

Read more (http://arxiv.org/PS_cache/astro-ph/pdf/0605/0605606.pdf) (68kb, PDF)

Kullat Nunu
2006-May-29, 05:10 PM
Kuiper Belt binaries seem to be very common. That 11% may be underestimate, since we can detect only wide binaries.

The situation is even more evident with the largest TNOs: Pluto has 3, 2003 EL61 2, 2003 UB313 and now Orcus has one satellite. Only 2005 FY9 and Sedna don't seem to have any moons.

2006-Jun-29, 08:28 PM
Nice link: