7066 Nessus

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7066 Nessus
Discovery and designation
Discovered by David L. Rabinowitz
Discovery time April 26, 1993
Names
Other names 1993 HA2
Group Centaur
Orbit[1]
Reference date December 31, 2006 (JD 2454100.5)
Longest distance from the Sun 5607.451 Gm (37.483 AU)
Shortest distance from the Sun 1769.167 Gm (11.826 AU)
Longest distance from the center of its orbital path
("semi-major axis")
3688.309 Gm (24.655 AU)
How egg-shaped its orbit is
("eccentricity")
0.520
How long it takes to complete an orbit 44714.802 d (122.42 a)
Average speed 5.57 km/s
Mean anomaly 43.762°
Angle above the reference plane
("inclination")
15.647°
Longitude of where it comes up through the reference plane 31.216°
Angle between its shortest distance from what it orbits around and where it comes up through the reference plane
("argument of periapsis")
170.814°
Size and Other Qualities
Measures 60±16 km[2][3]
Mass ~1.6×1017 kg
Average density 2.0? g/cm³
Gravity at its surface ~0.0148 m/s²
Slowest speed able to escape into space
("escape velocity")
~0.0280 km/s
How long it takes to turn around one time
(in relation to the stars)
? d
Angle at which it turns
(in relation to its orbit)
Latitude above the ecliptic ?
Longitude around the ecliptic ?
How much light it reflects 0.06[2]
Avg. surface temp. ~56 K
Light-band group
("spectral type")
?
True brightness
("absolute magnitude")
9.6[1]

7066 Nessus is a centaur (a type of icy planetoid) that was found by David L. Rabinowitz, working with Spacewatch, at Kitt Peak on 26 April, 1993. It was the second centaur found by him (5145 Pholus being his first), and the third centaur to be found (2060 Chiron was the first). It was officially announced on May 13, 1993 in IAUC 5789 with designation 1993 HA2.

Orbit[change | edit source]

Nessus finishes one orbit around the Sun in 122.4 years, an eccentricity of 0.52 and an inclination to the ecliptic of 15.6 degrees. At perihelion (closest approach to the Sun), it moves closer to the Sun than Uranus, while at aphelion (farthest approach to the Sun) it goes even farther thanNeptune.

The orbits of centaurs change from time to time because of interactions with the giant planets. Nessus is thought to have a fairly long orbital half-life of about 4.9 Myr.[4]

References[change | edit source]

  1. 1.0 1.1 "JPL Small-Body Database Browser: 7066 Nessus (1993 HA2)". 2004-05-26 last obs. http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Nessus. Retrieved 2008-09-05.
  2. 2.0 2.1 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 2008-10-18.
  3. Wm. Robert Johnston (22 August 2008). "List of Known Trans-Neptunian Objects". Johnston's Archive. http://www.johnstonsarchive.net/astro/tnoslist.html. Retrieved 2008-09-05.
  4. Horner, J.; Evans, N.W.; Bailey, M. E. (2004). Simulations of the Population of Centaurs I: The Bulk Statistics. http://arxiv.org/abs/astro-ph?papernum=0407400. Retrieved 2008-09-01.

Other websites[change | edit source]