35*25*25*0 @30% t ANCIENT SUNS Ron Brecher The globular star cluster Messier 10 is easy to spot in central Ophiuchus. Its densely concentrated stars are more than 11 billion years old. DETAILS: Astrosysteme Austria ASA Astrograph 10N with SBIG STL-11000M CCD camera. Total exposure: nearly 5 hours through LRGB filters. q GLOWING "PHANTOM" Eric Africa Cassiopeia's Sh 2-173, a cloud of glowing hydrogen listed in Stewart Sharpless' catalog, has been nicknamed Phantom of the Opera Nebula. DETAILS: Takahashi FSQ-106N astrograph with SBIG STL-11000M CCD camera. Total exposure: 14½ hours through Hα and RGB filters. Visit skyandtelescope.com/gallery for more of our readers' astrophotos. Gallery showcases the finest astronomical images submitted to us by our readers. Send your best shots to gallery@skyandtelescope.com. See skyandtelescope.com/aboutsky/guidelines. s k y a n d t e l e s c o p e .c o m * SEPTEMBER 2017 73http://www.skyandtelescope.com/gallery http://www.skyandtelescope.com/aboutsky/guidelines http://www.skyandtelescope.com