| Discovery | |
|---|---|
| Discovered by | Pan-STARRS 2 |
| Discovery site | Haleakala Obs. |
| Discovery date | 4 December 2020 |
| Designations | |
| MPC designation | 2020 XR |
| Minor planet category | |
| Orbital characteristics | |
| Epoch 2020-May-31 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 7.8 years |
| Aphelion | 4.0272 AU (602,460,000 km) (Q) |
| Perihelion | 0.97013 AU (145,129,000 km) (q) |
| Semi-major axis | 2.4987 AU (373,800,000 km) (a) |
| Eccentricity | 0.61174 (e) |
| Orbital period (sidereal) | 3.95 yr |
| Mean anomaly | 312.19° (M) |
| Inclination | 13.947° (i) |
| Longitude of ascending node | 249.74° (Ω) |
| Time of perihelion | 8 December 2020 |
| Argument of perihelion | 163.01° (ω) |
| Earth MOID | 0.00085 AU (127,000 km; 0.33 LD) |
| Jupiter MOID | 1.4 AU (210,000,000 km) |
| Physical characteristics | |
| Mean diameter | ~390 meters (1,000 feet) |
| Absolute magnitude (H) | 19.8 |
2020 XR is an Apollo near-Earth object and potentially hazardous asteroid roughly 390 meters (1,000 feet) in diameter. With a 5-day observation arc it was briefly listed as having a 1 in 11,000 chance of impacting Earth on 1 December 2028 placing it at the top of the Sentry Risk Table with a Palermo scale rating of -0.70.
Discovery
2020 XR was discovered by Pan-STARRS 2 on 4 December 2020, when it was 0.426 AU (63.7 million km) from Earth and had a solar elongation of 75°. It came to perihelion on 8 December 2020. On 2 January 2021, it passed 0.328 AU (49.1 million km) from Earth.
On 13 December 2020, precovery observations from 2013, 2016, and mid-2020 extended the observation arc from 8 days to 7.8 years allowing the asteroid to be removed from the Sentry Risk Table.
2024
It was the Earth perturbations of the asteroid in 2024 that determined if an impact was possible in December 2028. On 4 December 2024, the asteroid will pass 0.0147 AU (2.20 million km; 5.7 LD) from Earth with an uncertainty region of about ±800 km. This will increase the asteroid's orbital period by 10 days.
| Parameter | Epoch (date) |
Orbital Period |
|---|---|---|
| Units | (days) | |
| Pre-flyby | 2024-Sep-04 | 1441 |
| Post-flyby | 2025-Mar-04 | 1451 |
2028
On 7 November 2028, the asteroid will pass 0.121 AU (18.1 million km) from Earth. By 1 December 2028 the asteroid will be 0.19 AU (28 million km) from Earth with an uncertainty region of about ±10,000 km.
Notes
- While the observation arc was only a few days, the uncertainty region on 1 December 2028 was approximately a billion km.
References
- "MPEC 2020-X365 : 2020 XR". IAU Minor Planet Center. 7 December 2020. Retrieved 13 December 2020. (K20X00R)
- ^ "2020 XR". Minor Planet Center. Retrieved 13 December 2020.
- ^ "JPL Small-Body Database Browser: (2020 XR)" (last observation: 2020-12-12; arc: 7.8 years). Jet Propulsion Laboratory. Archived from the original on 13 December 2020. Retrieved 13 November 2020.
- ^ "Earth Impact Risk Summary: 2020 XR". NASA/JPL Near-Earth Object Program Office. Archived from the original on 10 December 2020. Retrieved 13 December 2020.
- hohmanntransfer: 2020 XR (10 Dec 2020) (1/11000 = 9E-05)
- "2020XR Ephemerides for 1 December 2028". NEODyS (Near Earth Objects – Dynamic Site). Archived from the original on 12 December 2020. Retrieved 13 December 2020.
External links
- Asteroid Hazards, Part 3: Finding the Path – YouTube video by the Minor Planet Center (26 August 2015)
- 2020 XR at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2020 XR at ESA–space situational awareness
- 2020 XR at Virtual Telescope Project
2020 XR at the JPL Small-Body Database
_on_Jul_14_2020_aligned_to_stars.jpg)
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