2022 UR4
Discovery Perihelion | 0.831 AU | |
---|---|---|
1.766 AU | ||
Eccentricity | 0.5294 | |
2.35 yr (857.0 days) | ||
36.030° | ||
0° 25m 12.279s / day | ||
Inclination | 11.292° | |
207.182° | ||
December 2022[4] | ||
238.577° | ||
Earth MOID | 0.000407 AU (60,900 km; 0.158 LD) | |
Jupiter MOID | 2.641 AU | |
Physical characteristics | ||
Mean diameter | 4.4–9.9 m (assumed albedo 0.05–0.25)[5] | |
28.90±0.45[4] | ||
2022 UR4 is a small
UTC.[4] It was discovered about 14 hours before closest approach by the Asteroid Terrestrial-impact Last Alert System (ATLAS) survey telescope at Mauna Loa Observatory, Hawaii on 20 November 2022.[2] During the close approach, the asteroid passed above the northern hemisphere of Earth and reached a peak brightness of magnitude 10,[2] just 40 times fainter than the threshold of naked eye visibility.[a]
Notes
- ^ The faintest magnitude that can be seen with the naked eye is about 6.[6] Using the formula Δm = −2.5 log10(F1/F2),[6] where Δm = m1 – m2 = 6 – 10 = –4 is the magnitude difference between the naked eye limit and 2022 UR4's peak brightness, the brightness ratio F1/F2 of the naked eye limit to the peak brightness of 2022 UR4 is approximately 39.81 ≈ F1/F2 = 10(Δm/–2.5).
References
- ^ a b c "2022 UR4". Minor Planet Center. Retrieved 30 November 2022.
- ^ a b c "MPEC 2022-U145 : 2022 UR4". Minor Planet Electronic Circular. Minor Planet Center. 21 October 2022. Retrieved 30 November 2022.
- ^ "2022 UR4". NEO Exchange. Las Cumbres Observatory. 20 October 2022. Retrieved 30 November 2022.
- ^ a b c d "JPL Small-Body Database Browser: (2022 UR4)" (2022-10-20 last obs.). Jet Propulsion Laboratory. Retrieved 30 November 2022.
- ^ "Asteroid Size Estimator". Center for Near Earth Object Studies. NASA. Retrieved 30 November 2022.
- ^ a b Mihos, Chris (2005). "The Magnitude Scale". Case Western Reserve University. Retrieved 30 November 2022.
External links
- 2022 UR4 at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2022 UR4 at ESA–space situational awareness
- 2022 UR4 at the JPL Small-Body Database