(164207) 2004 GU9 is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group. It will be a quasi-satellite of Earth until around 2600.[4]
| Discovery[1] | |
|---|---|
| Discovered by | LINEAR |
| Discovery site | Lincoln Lab’s ETS |
| Discovery date | 13 April 2004 |
| Designations | |
| NEO · Apollo | |
| Orbital characteristics[2] | |
| Epoch 13 January 2016 (JD 2457400.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 5424 days (14.85 yr) |
| Aphelion | 1.1376258581 AU (170.18640603 Gm) |
| Perihelion | 0.86490477 AU (129.387912 Gm) |
| 1.001265315 AU (149.7871591 Gm) | |
| Eccentricity | 0.1361882 |
| 1.00 yr (365.95 d) | |
| 154.915171° | |
| 0° 59m 1.464s / day | |
| Inclination | 13.6490265° |
| 38.6405971° | |
| 280.55672±0.00007° | |
| 2456145.53817±0.00006 jd | |
| 280.28542° | |
| Earth MOID | 0.000389702 AU (58,298.6 km) |
| Physical characteristics | |
| 160–360 meters[3] | |
| 0.219 | |
| 21.1[2] | |
On 14 April 2004 (with less than a 1-day observation arc), the Sentry Risk Table showed 180 virtual impactors.[5] It was removed from the Sentry Risk Table 2 days later on 16 April 2004.[6] (164207) 2004 GU9 now has a well determined orbit with an observation arc of 12 years.
This asteroid was discovered on 13 April 2004 by the Lincoln Near-Earth Asteroid Research project near Socorro, New Mexico and given the provisional designation 2004 GU9.[1] Following the naming of 524522 Zoozve, a quasi-satellite of Venus, Radiolab and the International Astronomical Union will hold a public naming campaign for this quasi-satellite from June to September 2024. The selected name will be announced in January 2025.[7][8]
![[en] | (164207) 2004 GU9](https://en.wikipedia.org/wiki/File:Animation_of_2004_GU9%27s_orbit_relative_to_Sun_and_Earth.gif)
![[en] | (164207) 2004 GU9](https://en.wikipedia.org/wiki/File:Animation_of_2004_GU9%27s_orbit_around_Earth.gif)
![[en] | (164207) 2004 GU9](https://en.wikipedia.org/wiki/File:Animation_of_2004_GU9%27s_orbit_around_Sun.gif)
- ^ a b “(164207) = 2004 GU9”. Minor Planet Center. Retrieved 3 June 2024.
- ^ a b “(164207) 2004 GU9”. JPL Small-Body Database. Jet Propulsion Laboratory. SPK-ID: 2164207. Retrieved 7 April 2016.
- ^ “Absolute Magnitude (H)”. NASA/JPL. Archived from the original on 2 March 2001.
- ^ Wajer, Paweł (October 2010). “Dynamical evolution of Earth’s quasi-satellites: 2004 GU9 and 2006 FV35”. Icarus. 209 (2): 488–493. Bibcode:2010Icar..209..488W. doi:10.1016/j.icarus.2010.05.012.
- ^ “Major News about Minor Objects: Risk monitoring”. hohmanntransfer. 14 April 2004. Archived from the original on 6 November 2020. Retrieved 2 March 2015.
- ^ “Date/Time Removed”. NASA/JPL Near-Earth Object Program Office. Archived from the original on 2 June 2002. Retrieved 1 March 2015.
- ^ “Competition Announced to Name a Quasi-Moon”. IAU. 31 May 2024. Retrieved 3 June 2024.
- ^ “OFFICIAL RULES: Name a Quasi Moon!”. Radiolab. Retrieved 3 June 2024.
Radiolab is partnering with the International Astronomical Union to launch a months-long global naming contest for one of Earth’s quasi-moons (asteroid 164207).
- Dynamical evolution of Earth’s quasi-satellites: 2004 GU9 and 2006 FV35 by Wajer, P. 2010, Icarus, Volume 209, Issue 2, pp. 488–493.
- (164207) 2004 GU9 at NeoDyS-2, Near Earth Objects—Dynamic Site
- (164207) 2004 GU9 at ESA–space situational awareness
- (164207) 2004 GU9 at the JPL Small-Body Database