List of asteroid close approaches to Earth in 2009
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| Asteroids which came closer to Earth than the Moon in 2009 by time of discovery | ||
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Below is the list of asteroid close approaches to Earth in 2009.
Warning times by size
A list of known near-Earth asteroid close approaches less than 1 lunar distance (384,400 km or 0.00257 AU) from Earth in 2009, based on the close approach database of the Center for Near-Earth Object Studies (CNEOS).[1]
The CNEOS database of close approaches lists some close approaches a full orbit or more before the discovery of the object, derived by orbit calculation. The list below only includes close approaches that are evidenced by observations, thus the pre-discovery close approaches would only be included if the object was found by precovery, but there was no such close approach in 2009.
This list and the relevant databases do not consider impacts as close approaches, thus this list does not include any of the objects that collided with Earth's atmosphere in 2009, none of which were discovered in advance, but were observed visually or recorded by sensors designed to detect detonation of nuclear devices.
Rows highlighted red indicate objects which were not discovered until after closest approach
Rows highlighted yellow indicate objects discovered less than 24 hours before closest approach
Rows highlighted green indicate objects discovered more than one week before closest approach
Rows highlighted turquoise indicate objects discovered more than 7 weeks before closest approach
Rows highlighted blue indicate objects discovered more than one year before closest approach
(i.e. objects successfully cataloged on a previous orbit, rather than being detected during final approach)
| Date of closest approach |
Date discovered |
Object | Nominal geocentric distance (AU)[note 1] |
Nominal geocentric distance (LD) |
Size (m) (approximate) |
(H) (abs. mag.) |
Closer approach to Moon |
Refs[2][3] |
|---|---|---|---|---|---|---|---|---|
| 2009-02-02 | 2009-02-04 | 2009 CC2 | 0.00126 AU (188,000 km; 117,000 mi) | 0.49 | 7.3–16 | 27.8 | data · 2009 CC2 | |
| 2009-02-27 | 2009-03-03 | 2009 EJ1 | 0.000411 AU (61,500 km; 38,200 mi) | 0.16 | 5.6–12 | 28.4 | data · 2009 EJ1 | |
| 2009-03-02 | 2009-02-27 | 2009 DD45 | 0.000483 AU (72,300 km; 44,900 mi) | 0.19 | 18–41 | 25.8 | data · 2009 DD45 | |
| 2009-03-06 | 2009-03-02 | 2009 EW | 0.00227 AU (340,000 km; 211,000 mi) | 0.88 | 14–31 | 26.4 | data · 2009 EW | |
| 2009-03-18 | 2009-03-17 | 2009 FH | 0.000568 AU (85,000 km; 52,800 mi) | 0.22 | 13–28 | 26.6 | data · 2009 FH | |
| 2009-03-19 | 2009-03-17 | 2009 FK | 0.00251 AU (375,000 km; 233,000 mi) | 0.98 | 5.8–13 | 28.3 | Yes | data · 2009 FK |
| 2009-05-05 | 2009-05-04 | 2009 JF1 | 0.00196 AU (293,000 km; 182,000 mi) | 0.76 | 7.6–17 | 27.7 | Yes | data · 2009 JF1 |
| 2009-05-13 | 2009-05-12 | 2009 JL2 | 0.00177 AU (265,000 km; 165,000 mi) | 0.69 | 17–38 | 26.0 | data · 2009 JL2 | |
| 2009-06-01 | 2009-05-31 | 2009 KR21 | 0.00190 AU (284,000 km; 177,000 mi) | 0.74 | 12–27 | 26.7 | Yes | data · 2009 KR21 |
| 2009-10-01 | 2009-10-02 | 2009 TB | 0.000464 AU (69,400 km; 43,100 mi) | 0.18 | 3.8–8.6 | 29.2 | data · 2009 TB | |
| 2009-10-05 | 2009-10-09 | 2009 TD17 | 0.00173 AU (259,000 km; 161,000 mi) | 0.67 | 7.7–17 | 27.7 | data · 2009 TD17 | |
| 2009-10-08 | 2009-10-10 | 2009 TU | 0.00204 AU (305,000 km; 190,000 mi) | 0.79 | 9.2–21 | 27.3 | data · 2009 TU | |
| 2009-10-17 | 2009-10-15 | 2009 TM8 | 0.00232 AU (347,000 km; 216,000 mi) | 0.90 | 5.6–12 | 28.4 | data · 2009 TM8 | |
| 2009-11-06 | 2009-11-06 | 2009 VA | 0.000137 AU (20,500 km; 12,700 mi) | 0.05 | 5.1–11 | 28.6 | data · 2009 VA | |
| 2009-11-12 | 2009-11-10 | 2009 VZ39 | 0.00174 AU (260,000 km; 162,000 mi) | 0.68 | 6.5–14 | 28.1 | Yes?[note 2] | data · 2009 VZ39 |
| 2009-11-15 | 2009-11-18 | 2009 WP6 | 0.00176 AU (263,000 km; 164,000 mi) | 0.69 | 12–26 | 26.8 | data · 2009 WP6 | |
| 2009-11-16 | 2009-11-18 | 2009 WQ6 | 0.00235 AU (352,000 km; 218,000 mi) | 0.91 | 3.8–8.6 | 29.2 | data · 2009 WQ6 | |
| 2009-11-20 | 2009-11-19 | 2009 WJ6 | 0.00119 AU (178,000 km; 111,000 mi) | 0.46 | 8.8–20 | 27.4 | data · 2009 WJ6 | |
| 2009-11-24 | 2009-11-23 | 2009 WV51 | 0.00101 AU (151,000 km; 94,000 mi) | 0.39 | 10–23 | 27.1 | data · 2009 WV51 |
This table visualizes the warning times of the close approaches listed in the above table, depending on the size of the asteroid. The sizes of each pie chart show the relative sizes of the asteroids to scale. For comparison, the approximate size of a person is also shown. This is based around the absolute magnitude of each asteroid, an approximate measure of size based on brightness.
Absolute magnitude H ≥ 30 (smallest)
None
Absolute magnitude 30 > H ≥ 29
(size of a person for comparison)
Absolute magnitude 28-29
Absolute magnitude 28 > H ≥ 27
Absolute magnitude 27 > H ≥ 26
Absolute magnitude 26 > H ≥ 25
- After closest approach: 0 (0.0%)
- < 24 hours before: 0 (0.0%)
- up to 7 days before: 1 (100.0%)
- > one week before: 0 (0.0%)
- > 7 weeks before: 0 (0.0%)
- > one year before: 0 (0.0%)
Absolute magnitude 25 > H (largest)
None
Notes
- ↑ Distance from the center of Earth to the center of the object. See the NASA/JPL Solar System Dynamics Glossary: Geocentric. Earth has a radius of approximately 6,400 km.
- ↑ The orbit of 2009 VZ39 is known quite poorly- it could have passed as closely as 0.029 and as far as 3.1 LD from Earth, as well as anything from 3.4 LD to colliding head-on with the Moon. As such, the values are based on the nominal calculations. Considering a fireball would likely be noticed if it had collided with the Moon, as it would have created a crater over 150 meters in diameter, it can probably be concluded that the actual orbit was not too far from the nominal one- with a closest approach somewhere between 0.5 and 0.8 lunar distances.
Additional examples
An example list of near-Earth asteroids that passed more than 1 lunar distance (384,400 km or 0.00256 AU) from Earth in 2009.
- (136849) 1998 CS1 (~990 meters in diameter) passed 11.33 Lunar distances (4.4 million km) from Earth on 17 January 2009.
- (208023) 1999 AQ10 (~285 meters in diameter) passed 4.39 Lunar distances (1.7 million km) from Earth on 18 February 2009.
- 2009 FW4 (~41 meters in diameter) passed 2.82 Lunar distances (1.1 million km) from Earth on 17 March 2009.
- 2009 DO111 (~95 meters in diameter) passed 1.22 Lunar distances (468,000 km) from Earth on 20 March 2009.
- (410777) 2009 FD (472 meters in diameter) passed 1.62 Lunar distances (624,000 km) from Earth on 27 March 2009.
- (136617) 1994 CC (~990 meters in diameter) passed 6.55 Lunar distances (2.5 million km) from Earth on 10 June 2009.
- 2009 MU (~41 meters in diameter) passed 2.31 Lunar distances (889,000 km) from Earth on 24 June 2009.
- 2009 RY3 (~41 meters in diameter) passed 1.94 Lunar distances (745,000 km) from Earth on 11 September 2009.
- 2009 SH1 (~5 meters in diameter) may have passed as close as 1.01 Lunar distances (390,000 km) from Earth on 14 September 2009, but the nominal orbit suggests an approach nearer to 2.40 LD (922,000 km).
- (68216) 2001 CV26 (1277 meters in diameter) passed 9.79 Lunar distances (3.8 million km) from Earth on 8 October 2009.
- (159402) 1999 AP10 (~2067 meters in diameter) passed 29.68 Lunar distances (11.4 million km) from Earth on 20 October 2009.
- 2009 WV25 (~54 meters in diameter) passed 2.91 Lunar distances (112,000 km) from Earth on 1 December 2009.
See also
References
- ↑ "NEO Earth Close Approaches". NASA/JPL CNEOS. Retrieved 27 February 2025.
- ↑ "JPL Small-Body Database Browser". JPL Solar System Dynamics. NASA Jet Propulsion Laboratory.
- ↑ "MPC Database". IAU Minor Planet Center. International Astronomical Union. Retrieved 1 January 2021.