astro.wikisort.org - Asteroid

(415713) 1998 XX₂ is a sub-kilometer asteroid, classified as a near-Earth object and potentially hazardous asteroid of the Aten group. It was discovered 8 December 1998, by the Lincoln Near-Earth Asteroid Research at Lincoln Laboratory's Experimental Test Site, and was found to have frequent approaches to the Earth, Venus, and Mercury.

(415713) 1998 XX₂

Discovery[1]
Discovered by	LINEAR
Discovery site	Lincoln Lab's ETS
Discovery date	8 December 1998
Designations
MPC designation	1998 XX2
Alternative designations	MPO 251988, MPO 315368
Minor planet category	NEO · Aten · PHA
Orbital characteristics[2]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc	5832 days (15.97 yr)
Aphelion	1.013611188 AU (151.6340754 Gm)
Perihelion	0.46896072 AU (70.155525 Gm)
Semi-major axis	0.741285953 AU (110.8948001 Gm)
Eccentricity	0.3673687
Orbital period (sidereal)	0.64 yr (233.1 d)
Average orbital speed	33.3946406 km/s
Mean anomaly	151.54037°
Mean motion	1.5442778°/day
Inclination	6.9722566°
Longitude of ascending node	74.444600°
Argument of perihelion	153.00166°
Earth MOID	0.0161402 AU (2.41454 Gm)
TJupiter	7.716
Physical characteristics
Mean diameter	270–590 m[3]
Absolute magnitude (H)	19.9[2]

Orbit

The orbit of 1998 XX₂ is well-established, and appears on the list of PHA close approaches to Earth, with the next approach at a distance of 0.020237 AU (3,027,400 km; 1,881,100 mi) on 28 November 2028.[4] During the years 1900–2200, close approaches are 0.017 AU (2,500,000 km; 1,600,000 mi) of the Earth (on 30 Nov 1991), as close as 0.035 AU (5,200,000 km; 3,300,000 mi) of Venus (on 28 Jan 1902 and 8 April 2039), and as close as 0.029 AU (4,300,000 km; 2,700,000 mi) of Mercury on 12 occasions.[2] For comparison, the distance to the Moon is about 0.0026 AU (384,400 km).^{[citation needed]}

From 1993 to 1998, 1993 DA was the asteroid with the lowest known aphelion at 1.023 AU, and was thus the closest thing to an Apohele asteroid known at the time. When (33342) 1998 WT24 was discovered 25 November 1998, it was found to have a slightly smaller aphelion (1.019 AU) than 1993 DA, so (33342) 1998 WT₂₄ took the title. However, (33342) 1998 WT₂₄ lost its smallest aphelion title almost immediately when (415713) 1998 XX₂ (aphelion of 1.014 AU) was discovered only a few weeks later on 8 December 1998.^{[citation needed]}

The Jupiter Tisserand invariant, used to distinguish different kinds of orbits, is 7.7.[2]

References

External links

• (415713) 1998 XX2 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
• (415713) 1998 XX2 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical Properties · Summary
• (415713) 1998 XX2 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

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