We present Hubble Space Telescope ( HST ) near-infrared photometry of the coldest known brown dwarf , WISE J085510.83 - 071442.5 ( WISE 0855 - 0714 ) .
WISE 0855 - 0714 was observed with the Wide Field Camera 3 ( WFC3 ) aboard HST using the F105W , F125W , and F160W filters , which approximate the Y , J , and H near-infrared bands .
WISE 0855 - 0714 is undetected at F105W with a corresponding 2 \sigma magnitude limit of \sim 26.9 .
We marginally detect WISE 0855 - 0714 in the F125W images ( S/N \sim 4 ) , with a measured magnitude of 26.41 \pm 0.27 , more than a magnitude fainter than the J - band magnitude reported by Faherty and coworkers .
WISE J0855 - 0714 is clearly detected in the F160W band , with a magnitude of 23.86 \pm 0.03 , the first secure detection of WISE 0855 - 0714 in the near-infrared .
Based on these data , we find that WISE 0855 - 0714 has extremely red F105W - F125W and F125W - F160W colors relative to other known Y dwarfs .
We find that when compared to the models of Saumon et al .
and Morley et al. , the F105W - F125W and F125W - F160W colors of WISE 0855 - 0714 can not be accounted for simultaneously .
These colors likely indicate that we are seeing the collapse of flux on the Wien tail for this extremely cold object .