PSR B1257+12
PSR B1257+12 , previously designated PSR 1257+12 , alternatively designated PSR J1300+1240 , is a pulsar located 2 , 300 light-years from the Sun in the constellation of Virgo . 
<triplet> PSR B1257+12 <subj> pulsar <obj> instance of <subj> Virgo <obj> constellation <triplet> Virgo <subj> constellation <obj> instance of