astro.wikisort.org - Asteroid

2017 XX₆₁ is a small near-Earth object, approximately 17 meters (56 feet) in diameter, that transited Earth at 8 lunar distances on 18 December 2017 at 14:54 UTC. The Apollo asteroid on an eccentric orbit was first observed by the Mount Lemmon Survey and was lost on the following night. As of 2020^[update], it has not been recovered.[2]

2017 XX₆₁

Discovery[1]
Discovered by	MLS
Discovery site	Mount Lemmon Obs.
Discovery date	15 December 2017
Designations
MPC designation	2017 XX61
Minor planet category	NEO · Apollo[1][2]
Orbital characteristics[2]
Epoch 16 December 2017 (JD 2458103.5)
Uncertainty parameter 8[2] · 7[1]
Observation arc	(1 day)
Aphelion	3.2799 AU
Perihelion	0.7945 AU
Semi-major axis	2.0372 AU
Eccentricity	0.6100
Orbital period (sidereal)	2.91 yr (1,062 days)
Mean anomaly	345.28°
Mean motion	0° 20m 20.4s / day
Inclination	8.4261°
Longitude of ascending node	81.755°
Argument of perihelion	67.340°
Earth MOID	0.0162 AU (6.3 LD)
Physical characteristics
Mean diameter	17 m (est. at 0.14)[3]
Absolute magnitude (H)	26.6[1][2]

Description

2017 XX₆₁ was first observed on 15 December 2017, by astronomers of the Mount Lemmon Survey at Mount Lemmon Observatory near Tucson, Arizona.[1]

It orbits the Sun at a distance of 0.8–3.3 AU once every 2 years and 11 months (1,062 days; semi-major axis of 2.04 AU). Its orbit has an eccentricity of 0.61 and an inclination of 8° with respect to the ecliptic.[2]

2017 XX₆₁ has an Earth minimum orbital intersection distance of 0.0162 AU (2,420,000 km), which translates into 6.3 lunar distances.[2] The asteroid also approached Mars on 11 May 2018.[2]

A generic magnitude-to-diameter conversion gives a mean-diameter of 13–27 meters, for an absolute magnitude of 26.6,[2] and an assumed albedo between 0.25 and 0.057, which typically correspond to the composition of a stony and carbonaceous body, respectively.[3]

References

External links

• 2017 XX61 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
• 2017 XX61 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical Properties · Summary
• 2017 XX61 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

---