The interactive map below shows our current prediction for the stellar occulation by (52246) Donaldjohanson on 2019 March 19 UT. The prediction is based on a Gaia DR2 position for the star and the v20181128185809 orbit estimate for Donaldjohanson.
Geocentric mid-time of the event is 18:54:01 UT. Star position is RA 20:07:51.1, Dec -18:51:16 (J2000), and its magnitude is 14.27. Donaldjohanson is moving at 31 km/s with respect to the star and its diameter is estimated to be 5 km, so central chords are expected to last 0.16 seconds.