The cold substellar frontier in JWST Extragalactic surveys: a robust parallax measurement yields the most distant known ultra-cold Y dwarf
We present an analysis of JADES-GS-BD-5, an extremely cold Y dwarf identified in the JADES/GOODS-South field. Using multi-epoch JWST/NIRCam imaging spanning a $\simeq2$-yr baseline, we calibrate the JWST astrometry and obtain the first robust parallax measurement for a brown dwarf discovered in a JWST extragalactic dee...