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High proper motion stars probe several extreme stellar populations, including nearby objects, Galactic halo stars, and hyper-velocity stars. Extending the search for high proper motion stars, to faint limits can increase their numbers and help to identify interesting targets. We conduct a search for faint (r>19.5 mag) high proper motion stars (>~200 mas/yr) by comparing the Sloan Digital Sky Survey (SDSS) - Data Release (DR) 10 catalog to the Pan-STARRS1-DR1 stacked image catalog. Our main selection criterion is stars that moved >1.5 arcsec and up to 7 arcsec between the SDSS and PS1 epochs. We identify 2923 high proper motion stars, of which 826 do not have proper motion in the GAIA-DR2 catalog and 565 are not listed in the GAIA-DR2 catalog. Our SDSS-PS1 proper motions are consistent with the GAIA-measured proper motions with a robust rms of about 10 mas/yr.
The GPS1 catalog was released in 2017. It delivered precise proper motions for around 350 million sources across three-fourths of the sky down to a magnitude of $rsim20$,mag. In this study, we present GPS1+ the extension GPS1 catalog down to $rsim22.
A faint star located 2 arcsec from KIC 8462852 was discovered in Keck 10 m adaptive optics imaging in the $JHK$ near-infrared (NIR) in 2014 by Boyajian et al. (2016). The closeness of the star to KIC 8462852 suggested the two could constitute a binar
We present an improved data-reduction technique to obtain high-precision proper motions (PMs) of globular clusters using Hubble Space Telescope data. The new reduction is superior to the one presented in the first paper of this series for the faintes
The UKIDSS Galactic Plane Survey (GPS) began in 2005 as a 7 year effort to survey ~1800 square degrees of the northern Galactic plane in the J, H, and K passbands. The survey included a second epoch of K band data, with a baseline of 2 to 8 years, fo
We compared high-contrast near-infrared images of the core of R136 taken by VLT/SPHERE, in two epochs separated by 3.06 years. For the first time we monitored the dynamics of the detected sources in the core of R136 from a ground-based telescope with