URAT1 is an observational, astrometric catalog covering most of the δ  −15°area and a magnitude range of about R = 3-18.5. Accurate positions (typically 10-30 mas standard error) are given for over 228 million objects at a mean epoch around 2013.5. For the over 188 million objects matched with the Two Micron All Sky Survey (2MASS) point-source catalog proper motions (typically 5-7 masyr -1 standard errors) are provided. These data are supplemented by 2MASS and AAVSO Photometric All-Sky Survey (APASS) photometry. Observations, reductions, and catalog construction are described, together with results from external data verifications. The catalog data are served by CDS, Starsbourg (I/329).

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Over the course of more than 10 years of continuous operations on the Martian surface, the operations team for the Mars Exploration Rovers has encountered and overcome many challenges. The twin rovers, Spirit and Opportunity, designed for a Martian surface mission of three months in duration, far outlived their life expectancy. Spirit explored for six years and Opportunity still operates and, in January 2014, celebrated the 10th anniversary of her landing. As with any machine that far outlives its design life, each rover has experienced a series of failures and degradations attributable to age, use, and environmental exposure. This paper reviews the failures and degradations experienced by the two rovers and the measures taken by the operations team to correct, mitigate, or surmount them to enable continued exploration and discovery.

The results of 4,747 intensified CCD observations of double stars, made with the 26-inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over two thousand short-exposure images. These observations are averaged into 2,667 mean relative positions and range in separation from 0.′′ 328 to 95. ′′ 9, with a median separation of 8.′′ 673. Four orbits are improved. This is the 22 nd in this series of papers and covers the period 4

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