  The Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission
observed comet C/2013 A1 (Siding Spring) three times at 3.4 {\mu}m and 4.6
{\mu}m as the comet approached Mars in 2014. The comet is an extremely
interesting target since its close approach to Mars in late 2014 will be
observed by various spacecraft in-situ. The observations were taken in 2014
Jan., Jul. and Sep. when the comet was at heliocentric distances of 3.82 AU,
1.88 AU, and 1.48 AU. The level of activity increased significantly between the
Jan. and Jul. visits but then decreased by the time of the observations in
Sep., approximately 4 weeks prior to its close approach to Mars. In this work
we calculate Af\r{ho} values, and CO/CO2 production rates.
