Building POCS: An open source observatory control system for amateur telescopes used by the PANOPTES project for the detection of extrasolar planets

The Panoptic Astronomical Networked OPtical observatory for Transiting Exoplanets Survey (PANOPTES, www.projectpanoptes.org) project is a citizen science project consisting of a wide network of low-cost imaging units built using commerically available products and working toward the identification of transiting exoplanets. The PANOPTES Observatory Control System (POCS) is a an open source software system designed to act as the control mechanism for the operation of the unit. POCS defines an Observatory class that is responsible for automated control of a commercially available equatorial mount, including image analysis and corresponding mount adjustment to obtain a percent-level photometric precision. Also responsible for controlling the two digital cameras and the archiving of 5 GB of nightly data, the Observatory class works via a state machine and in conjuction with a configurable target object scheduler, local environmental monitoring, and an inter-task messaging system for total hardware and software control. POCS is written in modern python and attempts to adhere to best practices within the astropy and scipy communities. An overview of the system is presented, along with key technical challenges and design considerations due to the open source and citizen science oriented aspect of PANOPTES.