 Orbit and positions of 2018 LA, 30 days before collision | |
| Discovery [1][2] | |
|---|---|
| Discovered by | Mount Lemmon Srvy. Richard Kowalski [3] |
| Discovery site | Mount Lemmon Obs. |
| Discovery date | 2 June 2018 |
| Designations | |
| 2018 LA | |
| ZLAF9B2 (NEOCP) | |
| NEO · Apollo [1][4] | |
| Orbital characteristics [4][5] | |
| Epoch 2 June 2018 (JD 2458271.5) | |
| Uncertainty parameter 8[4] · 6[1] | |
| Observation arc | 3.8 hours (14 obs.) |
| Aphelion | 1.9709 AU |
| Perihelion | 0.7820 AU |
| 1.3764 AU | |
| Eccentricity | 0.4319 |
| 1.61 yr (590 d) | |
| 326.73° | |
| 0° 36m 37.08s / day | |
| Inclination | 4.2975° |
| 71.870° | |
| 2018-Jul-26 | |
| 256.05° | |
| Earth MOID | < 5000 km |
| Venus MOID | 0.0557 AU |
| Mars MOID | 0.0191 AU |
| Physical characteristics | |
| 1.6–5.2 m (5.2–17.1 ft) (est. 0.05–0.3) 2.6–3.8 m (8.5–12.5 ft) (est. impact energy) | |
| Mass | 25–35 t (55,000–77,000 lbs.) |
| 0.15–0.30 (est. impact size) | |
| 18.3 (at discovery) | |
| 30.554[4] 30.6[1] | |
2018 LA, also known as ZLAF9B2, was a small Apollo near-Earth asteroid 2.6–3.8 m (9–12 ft) in mean diameter that impacted the atmosphere with small fragments reaching the Earth at roughly 16:44 UTC (18:44 local time) on 2 June 2018 near the border of Botswana and South Africa. It had been discovered only 8 hours earlier by the Mount Lemmon Survey, Arizona and based on 1+1⁄2 hours of observations, was calculated to have a roughly 85% chance of impact[6] likely somewhere between Australia and Madagascar.[7]
Hours later, a report arrived to the American Meteor Society that an observer from Botswana had seen a bright fireball. Shortly after the impact, the Asteroid Terrestrial-impact Last Alert System (ATLAS) released observations obtained from Hawaii roughly 2 hours after the Mount Lemmon observations which confirmed that the asteroid had indeed impacted Earth on a grazing path as per the observed fireball. A preliminary analysis of the pre-impact evolution of this meteoroid suggests that it may be part of a dynamical grouping.[8][9][10]
- ^ a b c d Cite error: The named reference
MPC-objectwas invoked but never defined (see the help page). - ^ Cite error: The named reference
MPEC2018-L04was invoked but never defined (see the help page). - ^ Cite error: The named reference
JPL-new-discoverywas invoked but never defined (see the help page). - ^ a b c d Cite error: The named reference
jpldatawas invoked but never defined (see the help page). - ^ Cite error: The named reference
projectplutoneocpwas invoked but never defined (see the help page). - ^ Cite error: The named reference
Gray85was invoked but never defined (see the help page). - ^ "Archived copy". Archived from the original on 16 September 2020. Retrieved 3 June 2018.
{{cite web}}: CS1 maint: archived copy as title (link) - ^ de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (18 June 2018). "On the Pre-impact Orbital Evolution of 2018 LA, Parent Body of the Bright Fireball Observed Over Botswana on 2018 June 2". Research Notes of the AAS. 2 (2): 57. arXiv:1806.05164. Bibcode:2018RNAAS...2...57D. doi:10.3847/2515-5172/aacc71. S2CID 242099557.
- ^ de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (26 July 2018). "Pre-airburst Orbital Evolution of Earth's Impactor 2018 LA: An Update". Research Notes of the AAS. 2 (3): 131. arXiv:1807.08322. Bibcode:2018RNAAS...2..131D. doi:10.3847/2515-5172/aad551. S2CID 240381194.
- ^ de la Fuente Marcos, C.; de la Fuente Marcos, R. (2019). "Waiting to make an impact: A probable excess of near-Earth asteroids in 2018 LA-like orbits". Astronomy and Astrophysics. 621: A137 (7 pp.). arXiv:1811.11845. Bibcode:2019A&A...621A.137D. doi:10.1051/0004-6361/201834313. S2CID 239287807.