WISE J085510.83 - 071442.5 was recently discovered as the coldest known brown dwarf based on four epochs of images from the Wide-field Infrared Survey Explorer and the Spitzer Space Telescope .
We have improved the accuracy of its parallax measurement by obtaining two additional epochs of Spitzer astrometry .
We derive a parallactic distance of 2.31 \pm 0.08 pc , which continues to support its rank as the fourth closest known system to the Sun when compared to WISE J104915.57 - 531906.1 AB ( 2.02 \pm 0.02 pc ) and Wolf 359 ( 2.386 \pm 0.012 pc ) .
The new constraint on the absolute magnitude at 4.5 µm indicates an effective temperature of 235–260 K based on four sets of theoretical models .
We also show the updated positions of WISE J085510.83 - 071442.5 in two color-magnitude diagrams .
Whereas Faherty and coworkers cited its location in M _ { W 2 } versus J - W 2 as evidence of water clouds , we find that those data can be explained instead by cloudless models that employ non-equilibrium chemistry .