▁ 5 ▁April ▁ 2 0 1 0 ▁that ▁extended ▁the ▁observation ▁arc ▁by ▁about ▁three ▁hours . ▁As ▁a ▁result ▁of ▁this ▁additional ▁observation , ▁the ▁new ▁orbit ▁is ▁closer ▁to ▁that ▁of ▁a ▁main ▁bel t ▁orbit ▁and ▁ ▁was ▁removed ▁from ▁the ▁S entry ▁R isk ▁Table ▁on ▁ 2 3 ▁February ▁ 2 0 1 8 . ▁ ▁Size ▁ ▁Not ▁only ▁is ▁the ▁orbit ▁of ▁ ▁poor ly ▁known , ▁but ▁also ▁the ▁size ▁is ▁largely ▁uncertain . ▁There ▁is ▁no ▁ground - based ▁phot ometry . ▁Based ▁on ▁the ▁W I SE ▁flux , ▁it ▁obtained ▁a ▁size ▁estimate ▁of ▁ 2   km , ▁which ▁should ▁be ▁seen ▁as ▁more ▁of ▁an ▁upper ▁limit . ▁ ▁Pre - 2 0 1 8 ▁orbit ▁solutions ▁ ▁Until ▁February ▁ 2 0 1 8 , ▁ ▁was ▁identified ▁in ▁only ▁ 1 4 ▁images , ▁and ▁the ▁observations ▁sp anned ▁a ▁very ▁short ▁observation ▁arc ▁of ▁ 1 ▁days ▁during ▁ 5 – 6 ▁April ▁ 2 0 1 0 . ▁On ▁ 5 ▁April ▁ 2 0 1 0 ▁the ▁astero id ▁was ▁estimated ▁to ▁have ▁been ▁ ▁from ▁Earth ▁with ▁an ▁uncertainty ▁in ▁the ▁astero ids ▁distance ▁of ▁ ± 5 0 0 ▁million ▁km . ▁With ▁peri hel ion ▁( clos est ▁approach ▁to ▁the ▁Sun ) ▁estimated ▁at ▁ 1 . 1 6 ▁ ± ▁ 3 . 5 ▁A U , ▁it ▁was ▁possible ▁this ▁astero id ▁bare ly ▁comes ▁inside ▁the ▁orbit