The interactive map below shows our current prediction for the stellar occultation by (52246) Donaldjohanson on 2019 August 25 UT. The prediction is based on a Gaia DR2 position for the star and the v20181128190051 orbit estimate for Donaldjohanson.
Geocentric mid-time of the event is 17:32:45 UT. Star position is RA 20:11:49.7, Dec -14:51:37 (J2000), and its magnitude is 14.20. Donaldjohanson is moving at 10 km/s with respect to the star and its diameter is estimated to be 5 km, so central chords are expected to last 0.50 seconds.