view of the telescopes and the relatively short exposure times enable approximately 6000 square degrees of sky to be imaged every night. The entire sky is 4π steradians, or 4π × (180/π)2 ≈ 41,253.0 square degrees, of which about 30,000 square degrees are visible from Hawaii, which means that the entire sky can be imaged in a period of 40 hours (or about 10 hours per night on four days). Given the need to avoid times when the Moon is bright, this means that an area equivalent to the entire sky will be surveyed four times a month, which is entirely unprecedented. By the end of its initial three-year mission in April 2014, PS1 had imaged the sky 12 times in each of 5 filters ('g', 'r', 'i', 'z', and 'y'). Filters 'g', 'r', and 'i' have the bandpasses of the Sloan Digital Sky Survey (SDSS) filters. (Midpoints and bandwidths at half maximum are 464 nm and 128 nm, 658 nm and 138 nm, and 806 nm and 149 nm, respectively.) The'z' filter has the SDSS midpoint (900 nm), but its longwave cutoff avoids water absorptions bands beginning at 930 nm. The shortwave cutoff of the 'y' filter is set by the water absorption bands that end around 960 nm. The longwave cutoff band is currently at 1030 nm to avoid the worst of the detector sensitivity to temperature variations. Science Pan-STARRS is currently mostly funded by a grant from the NASA Near Earth Object Observations program. It therefore spends 90% of its observing time in dedicated searches for Near Earth Objects. Systematically surveying the entire sky on a continuous basis is an unprecedented project and is expected to produce a dramatically larger number of discoveries of various types of celestial objects. For instance, the current leading asteroid discovery survey, the Mount Lemmon Survey, reaches an apparent magnitude of 22 V. Pan-STARRS will go about one magnitude fainter and cover the entire sky visible from Hawaii. The ongoing survey will also complement the efforts to map the infrared sky by the NASA WISE orbital telescope, with the results of one survey complementing and extending the other. The second data release, Pan-STARRS DR2, announced in January 2019, is the largest volume of astronomical data ever released. At over 1.6 petabytes of images, it is equivalent to 30,000 times the text content of Wikipedia. The data reside in the Mikulski Archive for