HaloSat: Observation Scheduling and the Cygnus Superbubble

HaloSat is a NASA-funded CubeSat that will measure X-rays from hot gas surrounding the Milky Way and address the question: is there a massive, extended, hot halo around the Milky Way? HaloSat was deployed on July 13, 2018, from the International Space Station. As of this writing, we are currently commissioning the science instrument which has soft X-ray detectors with a 10 degree diameter field of view. HaloSat will survey a large fraction of the sky by patterning the sky with targets. HaloSat observes only during the night side of each spacecraft orbit and the targets must be at Sun angles larger than 110 degrees to limit the foreground emission from the heliosphere. This causes us to have a limited visibility window for each target, which is also constrained by the limb angle of the Earth and the Moon's position. We will describe how our software schedules observations for each target such that they satisfy our requirements. For my senior thesis at the University of Iowa, I will also be using HaloSat to observe the Cygnus Superbubble. Preliminary results will be presented.