(792156) 2020 XR

(792156) 2020 XR
Goldstone Observatory radar images of 2020 XR and its satellite
Discovery
Discovered byPan-STARRS 2
Discovery siteHaleakala Obs.
Discovery date4 December 2020
Designations
Orbital characteristics
Epoch 2020-May-31 (JD 2459000.5)
Uncertainty parameter 0
Observation arc7.8 years
Aphelion4.0272 AU (602,460,000 km) (Q)
Perihelion0.97013 AU (145,129,000 km) (q)
2.4987 AU (373,800,000 km) (a)
Eccentricity0.61174 (e)
3.95 yr
312.19° (M)
Inclination13.947° (i)
249.74° (Ω)
8 December 2020
163.01° (ω)
Known satellites1
Earth MOID0.00085 AU (127,000 km; 0.33 LD)
Jupiter MOID1.4 AU (210,000,000 km)
Physical characteristics
~390 meters (1,000 feet)
19.8


(792156) 2020 XR is a binary 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, which placed 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. Permanent number was assigned on 31 March 2025.

Satellite

A satellite was discovered on 2 December 2024 by Goldstone Observatory in California using radar observations.

2024

It was the Earth's perturbations of the asteroid in 2024 that determined if an impact was possible in December 2028. On 4 December 2024, the asteroid passed 0.0147 AU (2.20 million km; 5.7 LD) from Earth with an uncertainty region of about ±800 km. This increased the asteroid's orbital period by 10 days.

Orbital period 3 months before and after 2024-Dec-04 Earth approach
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

  1. ↑ While the observation arc was only a few days, the uncertainty region on 1 December 2028 was approximately a billion km.

References

  1. ↑ "MPEC 2020-X365 : 2020 XR". IAU Minor Planet Center. 7 December 2020. Retrieved 13 December 2020. (K20X00R)
  2. 1 2 3 4 5 6 "2020 XR". Minor Planet Center. Retrieved 13 December 2020.
  3. 1 2 3 4 5 6 "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.
  4. 1 2 3 4 "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.
  5. ↑ hohmanntransfer: 2020 XR (10 Dec 2020) (1/11000 = 9E-05)
  6. 1 2 "(792156) 2020 XR". Wm. Robert Johnston. Retrieved 13 April 2025.
  7. ↑ "2020XR Ephemerides for 1 December 2028". NEODyS (Near Earth Objects – Dynamic Site). Archived from the original on 12 December 2020. Retrieved 13 December 2020.

(792156) 2020 XR at the JPL Small-Body Database