| Discovery | |
|---|---|
| Discovered by | LINEAR |
| Discovery site | Socorro |
| Discovery date | 13 April 2004 |
| Designations | |
|
Apollo |
|
| Orbital characteristics | |
| 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) |
| Jupiter MOID | 4.00854 AU (599.669 Gm) |
| Physical characteristics | |
| Dimensions | 160–360 meters |
| 21.1 | |
(164207) 2004 GU9 is a small near-Earth asteroid in the Apollo asteroid family. It will be a quasi-satellite of Earth until around 2600.
On 14 April 2004 (with less than a 1-day observation arc), the Sentry Risk Table showed 180 virtual impactors. It was removed from the Sentry Risk Table 2 days later on 16 April 2004.(164207) 2004 GU9 now has a well determined orbit with an observation arc of 12 years.