Advertisers in This Issue Astronomy equipment manufacturers and dealers are a valuable resource for amateur and professional astronomers alike. Patronize our advertisers in this issue and enjoy all the benefits of their expertise. Product Locator Astro-Physics, Inc. » page 81 mounts / telescopes astro-physics.com iOptron » page 65 mounts / telescopes ioptron.com QHYCCD Light Speed Vision » page 1 cameras qhyccd.com Sky-Watcher » inside front cover binoculars / mounts / telescopes skywatcherusa.com Software Bisque » page 5, 73 + back cover mounts bisque.com Stellarvue » inside back cover eyepieces / telescopes stellarvue.com Ad Index Arizona Sky Village Portal ......................... 81 Astro-Physics, Inc. ................................... 81 Bob's Knobs ............................................. 80 Bradford Exchange .................................. 79 Casitas de Gila Guesthouses .................... 81 Firefly Books .............................................. 3 iOptron .................................................... 65 Knightware .............................................. 81 Lunatico Astronomia ................................ 80 New Mexico Skies Astronomy Enclave ..... 81 NexDome ................................................. 80 Nine Planets Ring .................................... 81 Precise Parts ........................................... 80 QHYCCD Light Speed Vision ....................... 1 Revolution Imager .................................... 80 Sky & Telescope ...........................65, 75, 83 Sky-Watcher ............................................ C2 Software Bisque ............................ 5, 73, C4 Star-Hop Maker ....................................... 81 Stellarvue ................................................ C3 Technical Innovations ............................... 80 TravelQuest.............................................. 81 To advertise in our Product Locator, please contact Tim Allen at 773-551-0397, or email him at Ads@skyandtelescope.org 82 DECEMBER 2021 * SKY & TELESCOPEhttp://www.astro-physics.com http://www.skywatcherusa.com http://www.ioptron.com http://www.bisque.com http://www.qhyccd.com http://www.stellarvue.com