A list of known near-Earth asteroid close approaches less than 1 lunar distance (384,400 km or 0.00256 AU) from Earth in 2014.[note 1]
For reference, the radius of Earth is approximately 0.0000426 AU (6,370 km; 3,960 mi) or 0.0166 Lunar distances.The orbit of geosynchronous satellites, however, is 0.000282 AU (42,200 km; 26,200 mi) or 0.110 Lunar distances. This year, 3 asteroids were detected which traveled nearer than this, most notably 2014 AA, which impacted. This list does not include any of the other 32 objects that collided with earth in 2014, none of which were discovered in advance, but were recorded by sensors designed to detect detonation of nuclear devices (of the 33 objects detected 5 had an impact energy greater than that of a 1 kiloton device).[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)
This sub-section visualises the warning times of the close approaches listed in the above table, depending on the size of the asteroid. The sizes of the charts show the relative sizes of the asteroids to scale. For comparison, the approximate size of a person is also shown. This is based the absolute magnitude of each asteroid, an approximate measure of size based on brightness.
Abs Magnitude 30 and greater
(size of a person for comparison)
The number of asteroids listed here are significantly less than those of asteroids approaching Earth for several reasons:
These factors combined severely limit the amount of Moon-approaching asteroids, to a level many times lower than the detected asteroids to pass just as close to Earth instead.
An example list of near-Earth asteroids that passed more than 1 lunar distance (384,400 km or 0.00256 AU) from Earth in 2014.