The impact and recovery of asteroid 2018 LA
Creators: name: Jenniskens, Peter
name: Gabadirwe, Mohutsiwa
name: Yin, Qing-Zhu
name: Proyer, Alexander
name: Moses, Oliver
name: Kohout, Tomas
name: Franchi, Fulvio
name: Gibson, Roger L.
name: Kowalski, Richard
name: Christensen, Eric J.
name: Gibbs, Alex R.
name: Heinze, Aren
name: Denneau, Larry
name: Farnocchia, Davide
name: Chodas, Paul W.
name: Gray, William
name: Micheli, Marco
name: Moskovitz, Nick
name: Onken, Christopher A.
name: Wolf, Christian
name: Devillepoix, Hadrien A. R.
name: Ye, Quanzhi
name: Robertson, Darrel K.
name: Brown, Peter
name: Lyytinen, Esko
name: Moilanen, Jarmo
name: Albers, Jim
name: Cooper, Tim
name: Assink, Jelle
name: Evers, Läslo
name: Lahtinen, Panu
name: Seitshiro, Lesedi
name: Laubenstein, Matthias
name: Wantlo, Nggie
name: Moleje, Phemo
name: Maritinkole, Joseph
name: Suhonen, Heikki
name: Zolensky, Michael E.
name: Ashwal, Lewis
name: Hiroi, Takahiro
name: Sears, Derek W.
name: Sehlke, Alexander
name: Maturilli, Alessandro
name: Sanborn, Matthew E.
name: Huyskens, Magdalena H.
name: Dey, Supratim
name: Ziegler, Karen
name: Busemann, Henner
name: Riebe, My E. I.
name: Meier, Matthias M. M.
name: Welten, Kees C.
name: Caffee, Marc W.
name: Zhou, Qin
name: Li, Qiu-Li
name: Li, Xian-Hua
name: Liu, Yu
name: Tang, Guo-Qiang
name: McLain, Hannah L.
name: Dworkin, Jason P.
name: Glavin, Daniel P.
name: Schmitt-Kopplin, Philippe
name: Sabbah, Hassan
name: Joblin, Christine
name: Granvik, Mikael
name: Mosarwa, Babutsi
name: Botepe, Koketso
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The June 2, 2018, impact of asteroid 2018 LA over Botswana is only the second asteroid detected in space prior to impacting over land. Here, we report on the successful recovery of meteorites. Additional astrometric data refine the approach orbit and define the spin period and shape of the asteroid. Video observations of the fireball constrain the asteroid's position in its orbit and were used to triangulate the location of the fireball's main flare over the Central Kalahari Game Reserve. 23 meteorites were recovered. A consortium study of eight of these classifies Motopi Pan as a HED polymict breccia derived from howardite, cumulate and basaltic eucrite, and diogenite lithologies. Before impact, 2018 LA was a solid rock of about 156 cm diameter with high bulk density about 2.85 g/cm3, a relatively low albedo pV about 0.25, no significant opposition effect on the asteroid brightness, and an impact kinetic energy of about 0.2 kt. The orbit of 2018 LA is consistent with an origin at Vesta (or its Vestoids) and delivery into an Earth-impacting orbit via the nu_6 resonance. The impact that ejected 2018 LA in an orbit towards Earth occurred 22.8 +/- 3.8 Ma ago. Zircons record a concordant U-Pb age of 4563 +/- 11 Ma and a consistent 207Pb/206Pb age of 4563 +/- 6 Ma. A much younger Pb-Pb phosphate resetting age of 4234 +/- 41 Ma was found. From this impact chronology, we discuss what is the possible source crater of Motopi Pan and the age of Vesta's Veneneia impact basin.
description: Meteoritics &amp; Planetary Science (2021)