Thors Helmet from CFHT . ... Credit Copyright: Jean-Charles Cuillandre (CFHT), Hawaiian Starlight , CFHT Explanation: NGC 2359 is a striking emission nebula with an impressive popular name - Thor's Helmet Sure, its suggestive winged appearance might lead some to refer to it as the " duck nebula", but if you were a nebula which name would you choose? ... NGC 2359 is about 15,000 light-years distant toward the constellation Canis Major . ... NASA Web Site Statements, Warnings, and Disclaimers . ...