Revisiting the Parallax of the Isolated Neutron Star RX J185635-3754 Using HST/ACS Imaging

Understand

We have redetermined the parallax and proper motion of the nearby isolated neutron star RX~J185635-3754.

• We used eight observations with the high resolution camera of the HST/ACS taken from 2002 through 2004.
• We performed the astrometric fitting using five independent methods, all of which yielded consistent results.
• The mean estimate of the distance is 123 (+11, -15) pc (1 sigma), in good agreement with our earlier published determination.