|Discovered by||Deep Ecliptic Survey|
|Discovery time||22 May, 2001|
|Other names||2001 KX76|
|Reference date December 31, 2006 (JD 2 454 100.5)|
|Longest distance from the Sun||7 370.503 Gm (49.269 AU)|
|Shortest distance from the Sun||4 501.495 Gm (30.091 AU)|
|Longest distance from the center of its orbital path
|5 935.999 Gm (39.680 AU)|
|How egg-shaped its orbit is
|How long it takes to complete an orbit||91 295.847 d (249.95 a)|
|Average speed||4.66 km/s|
|Angle above the reference plane
|Longitude of where it comes up through the reference plane||71.028°|
|Angle between its shortest distance from what it orbits around and where it comes up through the reference plane
("argument of periapsis")
|Size and Other Qualities|
< 822 km diameter
|Area of its surface||< 2.24×106 km²|
|Volume inside it||< 3.15×108 km³|
|Average density||2.0? g/cm³|
|Gravity at its surface||< 0.229 7? m/s²|
|Slowest speed able to escape into space
|< 0.434 6? km/s|
|How long it takes to turn around one time||? d|
|How much light it reflects||0.15-0.37|
|Avg. surface temp.||≈44 K|
|(moderately red; B-V=1.03, V-R=0.61)|
28978 Ixion is a Kuiper belt object that was found on May 22, 2001. Ixion is a plutino (an object that has a 2:3 orbital resonance with Neptune) and could be a dwarf planet. Astronomers think that it has a diameter of about 800 km, which makes it the third biggest plutino. It is named after Ixion, a figure from Greek mythology. Before it was named Ixion, it had the provisional designation 2001 KX76.
References[change | change source]
- Marc W. Buie (2007-07-12). "Orbit Fit and Astrometric record for 28978". SwRI (Space Science Department). http://www.boulder.swri.edu/~buie/kbo/astrom/28978.html. Retrieved 2008-09-29.
- "JPL Small-Body Database Browser: 28978 Ixion (2001 KX76)". 2007-07-12 last obs. http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Ixion. Retrieved 2008-10-04.
- John Stansberry, Will Grundy, Mike Brown, Dale Cruikshank, John Spencer, David Trilling, Jean-Luc Margot (2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". University of Arizona, Lowell Observatory, California Institute of Technology, NASA Ames Research Center, Southwest Research Institute, Cornell University. http://arxiv.org/abs/astro-ph/0702538v2. Retrieved 2008-11-17.
- Wm. Robert Johnston. "TNO/Centaur diameters and albedos". http://www.johnstonsarchive.net/astro/tnodiam.html.
- Using the 2007 Spitzer spherical radius of 325 km; volume of a sphere * an assumed density of 2 g/cm³ yields a mass (m=d*v) of 2.8E+20 kg