(42301) 2001 UR163

Infobox Planet | discovery=yes | physical_characteristics=yes | bgcolour=#FFFFC0
name=mp|(42301) 2001 UR|163
discoverer=Deep Ecliptic Survey [ [http://cfa-www.harvard.edu/iau/lists/Centaurs.html List Of Centaurs and Scattered-Disk Objects ] ]
discovered=October 21, 2001
mp_name=mp|(42301) 2001 UR|163
alt_names="none"
mp_category=TNO (SDO)cite web
title=List Of Centaurs and Scattered-Disk Objects
publisher=Minor Planet Center
url=http://cfa-www.harvard.edu/iau/lists/Centaurs.html
accessdate=2008-09-25]
cite web
author=Marc W. Buie
date=2003/10/23
title=Orbit Fit and Astrometric record for 42301
publisher=SwRI (Space Science Department)
url=http://www.boulder.swri.edu/~buie/kbo/astrom/42301.html
accessdate=2008-09-25]
epoch=December 31, 2006 (JD 2454100.5)
semimajor=7693.969 Gm (51.431 AU)
perihelion=5498.582 Gm (36.756 AU)
aphelion=9889.356 Gm (66.106 AU)
eccentricity=0.285
period=134721.208 d (368.85 a)
inclination=0.752°
asc_node=301.769°
arg_peri=342.639°
mean_anomaly=68.401°
avg_speed=4.07 km/s
dimensions=636 km [ [http://www.johnstonsarchive.net/astro/tnoslist.html List of known trans-Neptunian objects ] ]
mass=2.7e|20? kg
density=2.0? g/cm³
surface_grav=0.1778? m/s²
escape_velocity=0.3362? km/s
sidereal_day=? d
spectral_type=(Super RED;highest B-R) B-V=1.44; V-R=0.84; B-R=2.28
abs_magnitude=3.97
albedo=0.10?
single_temperature=~39 K

mp|(42301) 2001 UR|163, also written as (42301) 2001 UR163, is a trans-Neptunian object (TNO) that resides in the Scattered disc. It was discovered on October 21, 2001 by the Deep Ecliptic Survey (DES) program at Kitt Peak.

mp|2001 UR|163 has the REDDEST color index of any object in the solar system. On October 31st, 2002, the 3.6 meter Canada-France-Hawaii telescope observed mp|2001 UR|163 set a record RED reading of B-R=2.28. This makes mp|2001 UR|163 even redder than 5145 Pholus, mpl|(119070) 2001 KP|77, 90377 Sedna, and comet C/2001 T4. Reddening of the spectrum is caused by cosmic irradiaton by ultraviolet radiation and charged particles. Becoming bluer in the spectrum is caused by impact collisions exposing the interior of an object. In the visible spectrum mp|2001 UR|163 would appear an orange-brown depending on its albedo.

References

External links

* [http://calys.obspm.fr/~pcorps/TNO/publi/doressoundiram2004_final_2MS.pdf The Meudon Multicolor Survey (2MS) of Centaurs and Trans-Neptunian objects]

* [http://www.psi.edu/pds/asteroid/EAR_A_COMPIL_3_TNO_CEN_COLOR_V3_0/data/tnocencol.tab TNO Colors]

* [http://www.physics.nau.edu/~tegler/research/survey.htm KBO Surface Colors]

* [http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001UR163;orb=1;view=Far Orbital simulation] from JPL (Java) / [http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=2001UR163 Ephemeris]

* [http://www.newscientist.com/article.ns?id=dn7272 Red Planetoid Sedna covered in tar-colored sludge]