July 20, 2015 - NewsRT @SETIInstitute: APOD: 2015 July 20 – Comet PanS… RT @SETIInstitute: APOD: 2015 July 20 – Comet PanSTARRS and a Crescent Moon buff.ly/1HKnPPO http://t.co/1j9OEq0ut5