2003 CP20

**2003 CP₂₀**
Discovery ^{A (http://cfa-www.harvard.edu/iau/lists/NumberedMPs.html)}
Discoverer	M. Blythe, F. Shelly, M. Bezpalko, R. Huber, L. Manguso, S. Adams, D. Torres, T. Brothers, S. Partridge / LINEAR
Discovery date	February 11, 2003
Alternate designations	^{B (http://cfa-www.harvard.edu/iau/MPDes.html)}
Category	Aten, Apohele Venus-crosser
Orbital elements ^{C (http://asteroid.lowell.edu/)} Epoch October 22, 2004 (JD 2453300.5)
Eccentricity (e)	0.322
Semi-major axis (a)	110.865 G m (0.741 AU)
Perihelion (q)	75.149 Gm (0.502 AU)
Aphelion (Q)	146.580 Gm (0.980 AU)
Orbital period (P)	233.023 d (0.64 a)
Mean orbital speed	33.68 km/s
Inclination (i)	25.618°
Longitude of the ascending node (Ω)	103.952°
Argument of perihelion (ω)	252.914°
Mean anomaly (M)	20.298°
Physical characteristics
Dimensions	~2.0 km
Mass	1.0×10¹² kg
Density	2.0? g/cm³
Surface gravity	0.0003 m/s²
Escape velocity	0.0005 km/s
Rotation period	? d
Spectral class	?
Absolute magnitude	16.43
Albedo	0.10
Mean surface temperature	~323 K

Discovered February 11, 2003, by the Lincoln Near-Earth Asteroid Research project's station at Socorro, New Mexico, 2003 CP₂₀ (also written 2003 CP20), was the first asteroid known to have an orbit entirely within that of Earth. Together with 2004 JG₆, which has an even smaller orbit, it forms a subclass of Aten asteroids, known as Apoheles. 2003 CP₂₀ takes slightly over 233 days to orbit the Sun. 2003 CP₂₀ is a Venus-crosser asteroid, but does not get as close to the Sun as Mercury. With a diameter of about 2 km, it is the larger of the two known Apoheles and is one of the larger Aten asteroids.

External links

Discovery Circumstances (http://earn.dlr.de/nea/K03C20P.htm)
Orbital Information (http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?objects:2003CP20;main)
Photo (http://www.klet.org/2003cp20.html)