Discovery date 2 June 2014 Discovered 2 June 2014 | MPC designation 2014 LY21 Observation arc ~1 hour Asteroid group Aten asteroid | |
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Discovered by Mt. Lemmon Survey (G96) Aphelion 1.0306 AU (154.18 Gm) (Q) Similar 2014 DX110, GU Piscium b, 2014 HQ124, 2014 OL339, Kepler‑421b | ||
2014 LY21 (also written 2014 LY21) is an Aten near-Earth asteroid roughly 4–8 meters (13–26 feet) in diameter that passed less than 0.00032 AU (48,000 km; 30,000 mi) from Earth around 3 June 2014 22:38 UT ± 14 hours. The asteroid was discovered on 2 June 2014 by the Mount Lemmon Survey at an apparent magnitude of 21 using a 1.5-meter (59 in) reflecting telescope.
With an observation arc of about 1 hour, the trajectory is poorly constrained and the asteroid has an uncertainty parameter of 9 making long-term predictions of the asteroids position nearly impossible. The nominal (best fit) orbit shows that 2014 LY21 passed 0.00012 AU (18,000 km; 11,000 mi) from Earth on 3 June 2014 (~11,600 km from Earth's surface). But the uncertainty region shows that the asteroid could have approached Earth as close as 0.00006 AU (9,000 km; 5,600 mi) or as far as 0.00032 AU (48,000 km; 30,000 mi). Since Earth has a radius of approximately 6,400 km, the asteroid did not come any closer than about 2,600 km from Earth's surface.
The nominal orbit shows that 2014 LY21 passed 0.001 AU (150,000 km; 93,000 mi) from the Moon on 4 June 2014. But the uncertainty region shows that the asteroid could have impacted the Moon or passed as far as 0.0044 AU (660,000 km; 410,000 mi). But it is very unlikely that the asteroid impacted the Moon.