(415713) 1998 XX2
(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.
Discovery[1] | |
---|---|
Discovered by | LINEAR |
Discovery site | Lincoln Lab's ETS |
Discovery date | 8 December 1998 |
Designations | |
1998 XX2 | |
MPO 251988, MPO 315368 | |
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) |
0.741285953 AU (110.8948001 Gm) | |
Eccentricity | 0.3673687 |
0.64 yr (233.1 d) | |
Average orbital speed | 33.3946406 km/s |
151.54037° | |
1.5442778°/day | |
Inclination | 6.9722566° |
74.444600° | |
153.00166° | |
Earth MOID | 0.0161402 AU (2.41454 Gm) |
TJupiter | 7.716 |
Physical characteristics | |
Dimensions | 270–590 m[3] |
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 November 28, 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 Nov 30, 1991), as close as 0.035 AU (5,200,000 km; 3,300,000 mi) of Venus (on Jan 28, 1902 and April 8, 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).
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 November 25, 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 December 8, 1998.
The Jupiter Tisserand invariant, used to distinguish different kinds of orbits, is 7.7.[2]
References
- "(415713) = 1998 XX2". Minor Planet Center. 2014-11-26.
- "JPL Small-Body Database Browser: 415713 (1998 XX2)" (last observation: 2014-11-26; arc: 5832 days). Jet Propulsion Laboratory. Retrieved 8 April 2016.
- "ABSOLUTE MAGNITUDE (H)". NASA.
- "PHA Close Approaches To The Earth". Minor Planet Center. Retrieved 2015-06-06.