We present astrometric results on two millisecond pulsars , PSR B1257+12 and PSR J1022+1001 , as carried out through VLBI .
For PSR B1257+12 , a model-independent distance of 710 _ { -38 } ^ { +43 } pc and proper motion of ( \mu _ { \alpha } = 46.44 \pm 0.08 mas/yr , \mu _ { \delta } = -84.87 \pm 0.32 mas/yr ) were obtained from 5 epochs of VLBA and 4 epochs of EVN observations , spanning about 2 years .
The two dimensional proper motion of PSR J1022+1001 ( \mu _ { \alpha } \sim -10.13 mas/yr , \mu _ { \delta } \sim 16.89 mas/yr ) was also estimated , using 3 epochs of EVN observations .
Based on our results , the X-ray efficiency of PSR B1257+12 should be in the same range as other millisecond pulsars , and not as low as previously thought .