Summary

2018 LA was the third object to be detected before impacting the Earth. The meteoroid was discovered at 08:22 UTC on 2 June 2018 by the Mount Lemmon Survey and impacted the atmosphere over Botswana eight hours later.

Discovery circumstances and follow-up

The discovery observations of 2018 LA were again obtained by Richard Kowalski, the discoverer of the two previous impacts, with the same Mt. Lemmon station of the Catalina Sky Survey in Arizona, USA. The discovery team successfully followed the object up with the same telescope and with their additional station at the Steward Observatory, and ensured sufficient observational coverage to evidence a likely impact a few hours after discovery. 

Subsequent observations by the ATLAS survey conclusively confirmed the impacting trajectory. A few months after the event, additional astrometry reported by the SkyMapper team further helped refine the trajectory, conclusively locating the event over Botswana. 

Trajectory in Space

In the video below, the vernal equinox is to the right, while the view is tilted 45 degrees to the ecliptic.

2D Impact Corridor

The plot below shows the entry point at an altitude of 100 km above the sea level.

3D Impact Corridor

The highlighted area in the animation below represents the 1-σ (in red) and the 3-σ (in orange) fall area of the propagated object without including the atmospheric effects.

Atmospheric Phase Details

Strong infrasound detections by the International Monitoring System (IMS) confirmed the event with an energy yield of 0.3-0.5 kt, corresponding to an asteroid of 2 metres in diameter. Several visual reports were submitted to the International Meteor Organization from Botswana and South Africa as well. 

Search for Meteorites

Fragments from the meteorite fall associated to this event were successfully recovered a few weeks after the impact. The meteorite, now known as Motopi Pan, has now been recognized as belonging to the HED family.