2021 GW4
| Discovery Perihelion | 0.97725 AU (146,195,000 km) (q) | |
|---|---|---|
| 1.511 AU (226,000,000 km) (a) | ||
| Eccentricity | 0.3532 (e) | |
| 1.862 yr (678 days) | ||
| 286.5° (M) | ||
| Inclination | 0.73712° (i) | |
| 201.52° (Ω) | ||
| 6 May 2021 | ||
| 26.568° (ω) | ||
| Earth MOID | 0.00012 AU (18,000 km; 0.047 LD) | |
| Jupiter MOID | 2.9 AU (430,000,000 km) | |
| Physical characteristics | ||
Mean diameter | 3–8 meters (CNEOS) | |
| 29.5[2] | ||
2021 GW4 is an
Apollo near-Earth object roughly 5 meters (20 feet) in diameter. It was discovered by the Mount Lemmon Survey on 8 April 2021.[1] On 12 April 2021 13:01 UTC it passed 19821 km from the surface of Earth.[3] The uncertainty in the close approach distance was ±30 km.[4]
The Earth approach caused the asteroid to migrate inward and reduced the
perihelion
(closest approach to the Sun) on 6 May 2021.
References
- ^ a b "MPEC 2021-G121 : 2021 GW4". IAU Minor Planet Center. 9 April 2021. Retrieved 17 April 2021. (K21G04W)
- ^ a b c "JPL Small-Body Database Browser: (2021 GW4)" (last observation: 2021-04-12; arc: 4 days; JPL #6). Jet Propulsion Laboratory. Retrieved 17 April 2021.
- ^ 2021-Apr-12 Earth approach: 0.000175131 AU (26,199.2 km). 26199km "geocentric distance" – 6378km "Earth radius" = 19821km
- ^ "Horizons Batch for 2021-Apr-12 13:01 showing RNG_3sigma uncertainty of ±29.7km". JPL Horizons. Retrieved 17 April 2021.
- JPL SBDBnumbers and "2021-Jun-17" with a step size of 6 months.)
- ^ a b Meteor scientist Peter Brown
- ^ Astronomer Jonathan McDowell
- ^ Astronomer Michael Busch
- ^ "Fireball FAQS: How frequently do fireballs occur?". American Meteor Society. Retrieved 17 April 2021.
External links
- 2021 GW4 at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2021 GW4 at ESA–space situational awareness
