List of asteroid close approaches to Earth in 2014

Below is the list of asteroid close approaches to Earth in 2014.

A list of known near-Earth asteroid close approaches less than 1 lunar distance (384,400 km or 0.00257 AU) from Earth in 2014, based on the close approach database of the Center for Near-Earth Object Studies (CNEOS).

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 2014.

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 into Earth's atmosphere and burnt up. This list and relevant databases do not consider impacts as close approaches, thus this list does not include predicted asteroid impacts or any of the other 32 objects that collided with Earth's atmosphere in 2014, 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)

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.

Absolute magnitude H ≥ 30 (smallest)

(size of a person for comparison)

Absolute magnitude 30 > H ≥ 29

Absolute magnitude 29 > H ≥ 28

Absolute magnitude 28 > H ≥ 27

Absolute magnitude 27 > H ≥ 26

Absolute Magnitude 26 > H ≥ 25

•   After closest approach: 1 (50.0%)
•   < 24 hours before: 0 (0.0%)
•   up to 7 days before: 1 (50.0%)
•   > one week before: 0 (0.0%)
•   > 7 weeks before: 0 (0.0%)
•   > one year before: 0 (0.0%)

Absolute magnitude 25 > H (largest)

None

The number of asteroids listed here are significantly less than those of asteroids approaching Earth for several reasons:

• Asteroids approaching Earth not only move faster, but are brighter and are easier to detect with modern surveys due to these factors
• Asteroids approaching closer to Earth are higher priority to confirm, and only confirmed asteroids are listed with a lunocentric approach distance
• Those which make close approaches to the Moon are frequently lost in its glare, making them harder to confirm, and are more easily discovered during the new Moon, when the Moon is too close to the Sun for any asteroids to be detected while they are near to the Moon anyway.

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.

• (388188) 2006 DP14 (~300 meters in diameter) passed 6.2 lunar distances from Earth on 10 February 2014.
• 2000 EM26 (~200 meters in diameter) passed more than 0.018 AU (2,700,000 km; 1,700,000 mi) from Earth on 17–18 February 2014.
• 2014 HJ₁₉₇ (~3 meters in diameter) may have passed as close as 0.97 lunar distances (371,000 km) from Earth (0.68 lunar distances (261,000 km) from the Moon on either April 14 or 15th, 2014, but the nominal orbit calculates an approach of 1.29 lunar distances (495,000 km) from Earth (1.23 lunar distances (473,000 km) from the Moon).
• 2014 KH₃₉ (~25 meters in diameter) passed 1.1 lunar distances from Earth on 3 June 2014.
• 2014 HQ124 (~325 meters in diameter) passed 3.25 lunar distances from Earth on 8 June 2014.
• 2014 OO6 (~75 meters in diameter) passed 0.0297 AU (4,440,000 km; 2,760,000 mi) from Earth on 18 August 2014.
• 2014 XL7 (~230 meters in diameter) passed roughly 0.26 AU (39,000,000 km; 24,000,000 mi) from Earth on 1 September 2014.
• The orbit of 2009 RR (20–45 meters in diameter) with an observation arc of only 4 days predicted that it could pass just inside 1 lunar distance on 2014-09-16, but the orbital uncertainties show that it could have passed as much as 0.1 AU (15,000,000 km; 9,300,000 mi) from Earth.
• 2014 SN₁₄₂ (~10 meters in diameter) passed 1.1 lunar distances from Earth on 23 September 2014.
• 2014 SC324 (~60 meters in diameter) passed 1.5 lunar distances from Earth on 24 October 2014.

• List of asteroid close approaches to Earth
• List of asteroid close approaches to Earth in 2013
• List of asteroid close approaches to Earth in 2015