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2003 YN107

2003 YN107
Discovery
Discovered by LINEAR
Discovery date December 20, 2003
Designations
Aten
Orbital characteristics
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc 467 days (1.28 yr)
Aphelion 1.00244 AU (149.963 Gm)
Perihelion 0.974906 AU (145.8439 Gm)
0.988674 AU (147.9035 Gm)
Eccentricity 0.0139259
0.98 yr (359.1 d)
Average orbital speed
29.82 km/s
176.9658°
1.00259°/day
Inclination 4.32078°
264.41926°
87.50070°
Earth MOID 0.0045919 AU (686,940 km)
Jupiter MOID 3.9854 AU (596.21 Gm)
Physical characteristics
Dimensions 10–30 m
Mass ~1–28×106 kg
Equatorial surface gravity
~3–8×10−6 m/s²
Equatorial escape velocity
~5–16×10−6 km/s
Temperature ~279 K
26.5

2003 YN107, also written 2003 YN107, is a very small near-Earth object moving in a 1:1 mean-motion resonance with Earth. Because of that, it is in a co-orbital configuration relative to Earth.

It was discovered by the Lincoln Near Earth Asteroid Research (LINEAR) system in orbit around the Sun on December 20, 2003. Its diameter is approximately 10 to 30 metres. 2003 YN107 is on NASA's Earth Close Approach list, and is estimated to miss Earth by 0.01 AU. It revolves around the Sun on an Earth-like, almost circular, orbit. Its orbital period of 363.846 days also is very close to the sidereal year.

From approximately 1997 to 2006, the asteroid remained within 0.1 AU (15,000,000 km; 9,300,000 mi)) of Earth and it appeared to slowly orbit Earth. However, 2003 YN107 is no second moon, as it is not bound to Earth. It is the first discovered member of a postulated group of coorbital objects, or quasi-satellites, which show these path characteristics. Other members of this group include 10563 Izhdubar, 54509 YORP, (66063) 1998 RO1, (85770) 1998 UP1, and (85990) 1999 JV6. Before 1996, the asteroid had been on a so-called horseshoe orbit around the Sun, along the Earth's orbit. After 2006, it had regained such an orbit. This makes it very similar to 2002 AA29, which will become a quasi-satellite of Earth in approximately 600 years.


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