Star cluster. Optical image of the open star cluster M35 (centre left) in the zodiacal conste- llation Gemini, the twins. North is at top. M35 contains hundreds of stars and lies around 2800 light years from Earth. Open clusters comprise young stars which were born at the same time from the same gas cloud. Directly below M35 at lower left is the faint red emission nebula NGC 2174. The bright star just below and to the left of M35 is Propus (Eta Geminorum). The bright stars at upper and lower right are El Nath (Beta Tauri) and Zeta Tauri respectively, in the neighbouring constellation Taurus, the bull. This area is best observed in winter from the northern hemisphere.