(417634) 2006 XG1

(417634) 2006 XG₁ provisional designation 2006 XG₁, is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, that had a low but non-zero probability of impacting Earth on 31 October 2041. The asteroid was discovered on 20 September 2006, by astronomers of the Catalina Sky Survey, using a dedicated 0.68-meter telescope at Mount Lemmon Observatory in Arizona, United States.^[2][3][5]

(417634) 2006 XG₁

Discovery[1][2][3]
Discovered by	CSS
Discovery site	Mount Lemmon Obs.
Discovery date	11 December 2006
Designations
MPC designation	(417634) 2006 XG1
Alternative designations	2006 XG1
Minor planet category	Apollo NEO PHA[1][2]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	8.09 yr (2,956 days)
Aphelion	3.9218 AU
Perihelion	0.9943 AU
Semi-major axis	2.4580 AU
Eccentricity	0.5955
Orbital period (sidereal)	3.85 yr (1,408 days)
Mean anomaly	287.03°
Mean motion	0° 15m 20.88s / day
Inclination	20.493°
Longitude of ascending node	38.478°
Argument of perihelion	344.11°
Earth MOID	0.0157 AU (6.1 LD)
Physical characteristics
Mean diameter	0.418±0.081 km[4]
Mass	4.2×1011 kg (estimate)
Geometric albedo	0.154±0.061[4]
Absolute magnitude (H)	18.5[1]

Description

Originally listed with a Torino Scale hazard rating of 0, this was raised to a rating of 1 on 22 December 2006 as a result of additional observations and refinement of the orbital calculations.^[5] However, on 9 January 2007 it was returned to a rating of 0. It was removed from the Sentry Risk Table on 7 February 2007.^[6]

It is now known that the asteroid will not make a close approach to the Earth in 2041.^[1] On 31 October 2041, the asteroid will be 1.69 AU (253,000,000 km; 157,000,000 mi) from the Earth.^[7][8] 2006 XG₁ passed 0.0298 AU (4,460,000 km; 2,770,000 mi) from asteroid 87 Sylvia on 20 June 1969.^[1] It is also a Mars-crosser asteroid.

Physical characteristics

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, 2006 XG₁ measures 418 meters in diameter and its surface has an albedo of 0.154.^[4] Previously, JPL's Sentry System estimated a diameter of 670 meters with a mass of 4.2×10¹¹ kg.^{[citation needed]}