News

News

UKIRT Hemisphere Surveys (UHS)

Conducted by the US Naval Observatory (USNO) in partnership with the UH IfA, Cambridge Astronomical Survey Unit, and the Wide-Field Astronomy Unit, ROE, Edinburgh using the UKIRT Wide Field Camera (WFCAM) covering the northern sky from 0 — +60° in declination (12,700 sq. degrees), UHS has data releases in J and more recently K-bands. Surveys done in H-band are nearly complete with a new survey of Y-band and a reobservation in J-band starting in late 2023. Regions previously covered in the UKIDSS sky survey have been excluded in the current rounds of the UHS survey.

You can see a current coverage chart in each band individually or altogether at this link: http://casu.ast.cam.ac.uk/wfcamsp/uhs

Redder than Red: Discovery of an Exceptionally Red L/T Transition Dwarf (Schneider A. et al., 2023, ApJ, 943L..16)

UKIRT has discovered a free-floating planetary mass brown dwarf, J050626.96+073842.4 (pictured below).

J050626.96+073842.4 has the reddest known colors of any brown dwarf around L/T transition young and very dusty atmosphere. Below is photometric data from the UHS survey and the USNO-UKIRT parallax.

Astronomy and Photometry for ~1000 L, T, and Y Dwarfs from the UKIRT Hemisphere Survey (Schneider A. et al., 2023AJ, 166, 103)

From the UHS, UKIRT has ascertained the positions, photometry and proper motions for 966 known Brown Dwarfs. The measured proper motions are more precise than those from CatWISE and Pan-STARRS, but not Gaia – a valuable resource for non-Gaia point sources. The figure below is a comparison between the proper motion measurements and those from Gaia, CatWISE, and Pan-STARRS.