W A HERCULEAN GLOBUL AR Patrick Winkler The Great Globular Cluster in Hercules, M13, brims with bright, densely packed stars. Under extremely dark skies, sharpeyed observers may spot it as a hazy blur without optical aid, but a mid-size telescope can resolve individual stars. DETAILS: AstroSysteme Austria ASA RC400 Ritchey-Chrétien telescope with ZWO ASI6200MM MC Pro CMOS camera. Total exposure: 3½ hours through LRGB filters. T LOOPING AROUND GEMINI Tunç Tezel This image follows Mercury as it draws a retrograde loop around the legs of the Gemini twins during the summer of 2020. The Solar and Heliospheric Observatory captured the tiny images of Mercury on the far side of the loop before and after it reached inferior conjunction on July 1st. DETAILS: Canon EOS 6D DSLR with 50-mm lens. Composite of 28 exposures captured at ISO 200, 400, and 800. s k y a n d t e l e s c o p e . o r g * J U LY 2 0 2 1 77http://www.skyandtelescope.org