Below is the list of asteroid close approaches to Earth in 2008. 2008 was the first year that an asteroid was successfully detected before it impacted earth (2008 TC3 was the first successfully predicted asteroid impact).
| 2008 | |
After closest approach: 11 (52.4%) <24 hours before: 2 (9.5%) Up to 7 days before: 8 (38.1%) > one week before: 0 (0%) > 7 weeks before: 0 (0%) > one year before: 0 (0%)
Time of discovery of asteroids which came closer to Earth than the moon in 2008 | |
| Other Years | |
|---|---|
| 2000-2007, 2008, 2009, 2010 |
Timeline of close approaches less than one lunar distance from Earth in 2008
editA list of known near-Earth asteroid close approaches less than 1 lunar distance (384,400 km or 0.00257 AU) from Earth in 2008.[note 1]
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)
Apart from 2008 TC3, this list does not include any of the other objects that collided with earth in 2008 as they were not discovered in advance, but were recorded by sensors designed to detect detonation of nuclear devices.[note 2]
| Date of closest approach |
Date discovered |
Object | Nominal geocentric distance (AU)[note 3] |
Nominal geocentric distance (LD) |
Size (m) (approximate) |
(H) (abs. mag) |
Closer approach to Moon |
Refs[1][2] |
|---|---|---|---|---|---|---|---|---|
| 2008-01-13 | 2008-01-10 | 2008 AF3 | 0.00252 AU (377,000 km; 234,000 mi) | 0.98 | 16–36 | 26.1 | data · 2008 AF3 | |
| 2008-01-16 | 2008-01-19 | 2008 BW2 | 0.00238 AU (356,000 km; 221,000 mi) | 0.93 | 3.1–6.8 | 29.7 | data · 2008 BW2 | |
| 2008-01-31 | 2008-01-30 | 2008 BC15 | 0.00198 AU (296,000 km; 184,000 mi) | 0.77 | 13–28 | 26.6 | Yes | data · 2008 BC15 |
| 2008-02-05 | 2008-02-03 | 2008 CT1 | 0.00089 AU (133,000 km; 83,000 mi) | 0.35 | 7.7–17 | 27.7 | data · 2008 CT1 | |
| 2008-02-15 | 2008-02-09 | 2008 CK70 | 0.00248 AU (371,000 km; 231,000 mi) | 0.97 | 28–62 | 24.9 | data · 2008 CK70 | |
| 2008-03-09 | 2008-03-07 | 2008 EZ7 | 0.00108 AU (162,000 km; 100,000 mi) | 0.42 | 11–24 | 27.0 | data · 2008 EZ7 | |
| 2008-03-10 | 2008-03-11 | 2008 EF32 | 0.00044 AU (66,000 km; 41,000 mi) | 0.17 | 3.5–7.8 | 29.4 | data · 2008 EF32 | |
| 2008-03-10 | 2008-03-08 | 2008 EM68 | 0.00148 AU (221,000 km; 138,000 mi) | 0.57 | 8.4–19 | 27.5 | data · 2008 EM68 | |
| 2008-03-23 | 2008-03-27 | 2008 FK | 0.00218 AU (326,000 km; 203,000 mi) | 0.85 | 9.2–21 | 27.3 | Yes | data · 2008 FK |
| 2008-03-29 | 2008-03-28 | 2008 FP | 0.00114 AU (171,000 km; 106,000 mi) | 0.44 | 15–33 | 26.3 | data · 2008 FP | |
| 2008-04-03 | 2008-04-06 | 2008 GM2 | 0.00139 AU (208,000 km; 129,000 mi) | 0.54 | 5.8–13 | 28.3 | data · 2008 GM2 | |
| 2008-04-07 | 2008-04-05 | 2008 GF1 | 0.00196 AU (293,000 km; 182,000 mi) | 0.76 | 5.8–13 | 28.3 | Yes | data · 2008 GF1 |
| 2008-05-10 | 2008-05-11 | 2008 JL24 | 0.00115 AU (172,000 km; 107,000 mi) | 0.45 | 3.2–7.1 | 29.6 | Yes | data · 2008 JL24 |
| 2008-07-29 | 2008-07-30 | 2008 OT7 | 0.00116 AU (174,000 km; 108,000 mi) | 0.45 | 10–23 | 27.1 | data · 2008 OT7 | |
| 2008-10-03 | 2008-10-08 | 2008 TN9 | 0.00165 AU (247,000 km; 153,000 mi) | 0.64 | 7.3–16 | 27.8 | data · 2008 TN9 | |
| 2008-10-07 | 2008-10-06 | 2008 TC3 | impact | impact | 4.1 | 30.4[3] | data · 2008 TC3 | |
| 2008-10-09 | 2008-10-09 | 2008 TS26 | 0.0000844 AU (12,630 km; 7,850 mi) | 0.03 | 0.61–1.4 | 33.2 | data · 2008 TS26 | |
| 2008-10-18 | 2008-10-29 | 2008 UA202 | 0.00223 AU (334,000 km; 207,000 mi) | 0.87 | 3.5–7.8 | 29.4 | data · 2008 UA202 | |
| 2008-10-20 | 2008-10-21 | 2008 US | 0.00022 AU (33,000 km; 20,000 mi) | 0.09 | 1.4–3.1 | 31.4 | data · 2008 US | |
| 2008-10-22 | 2008-10-22 | 2008 UM1 | 0.00057 AU (85,000 km; 53,000 mi) | 0.22 | 1.0–2.3 | 32.1 | data · 2008 UM1 | |
| 2008-11-03 | 2008-11-03 | 2008 VM | 0.00031 AU (46,000 km; 29,000 mi) | 0.12 | 2.4–5.4 | 30.2 | data · 2008 VM |
Warning Times by Size
editThis 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.
| Comments | Relative Size |
|---|---|
(size of a person for comparison)
|
 |
Absolute Magnitude 30 and Greater
|
|
Absolute Magnitude 29-30
|
|
Absolute Magnitude 28-29
|
|
Absolute Magnitude 27-28
|
|
Absolute Magnitude 26-27
|
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Absolute Magnitude 25-26
|
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Absolute Magnitude Less than 25 (Largest)
|
|
Notes
edit- ^ For a list of current Earth close approaches see NEO Earth Close Approaches
- ^ Asteroids which collide with earth before being detected never receive a designation and do not appear in either the NASA or IAU lists of asteroids as there is no astrometry for them.
- ^ 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.
Additional examples
editAn example list of near-Earth asteroids that passed more than 1 lunar distance (384,400 km or 0.00256 AU) from Earth in 2008.
- 2007 TU24 (~250 meters in diameter) passed 1.44 LD (554,000 km) from Earth on January 29, 2008.
- 2008 CE22 (~18 meters in diameter) passed between 0.9997 and 1.0023 LD (384,300 to 385,300 km) from Earth on February 6, 2008.
- (450894) 2008 BT18 (~650 meters in diameter) passed 5.9 LD (2.3 million km) from Earth on July 14, 2008.
- 2008 XK (~12 meters in diameter) may have passed as close as 0.23 LD (89,300 km) from Earth on December 5, 2008, but the nominal orbit suggests it passed nearer to 1.46 LD (560,500 km) from Earth instead.
See also
editReferences
edit- ^ "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.
- ^ "JPL Small-Body Database Browser: (2008 TC3)" (last observation: 2008-10-07).