The interactive map below shows our current prediction for the stellar occulation by (52246) Donaldjohanson on 2019 June 20 UT. The prediction is based on a Gaia DR2 position for the star and the v20181128185937 orbit estimate for Donaldjohanson.
Geocentric mid-time of the event is 03:32:34 UT. Star position is RA 21:05:07.3, Dec -12:48:50 (J2000), and its magnitude is 13.00. Donaldjohanson is moving at 5 km/s with respect to the star and its diameter is estimated to be 5 km, so central chords are expected to last 1.0 seconds.