I coined this phrase back in the early 80's, while observing it with my 17.5 Dob. I've never been able to see "Thor's Helmet", it's "new" familiar name. It will always look like a snail to me.
Thors Helmet or a Snail, you decide ?
Edited by 17.5Dob, 22 August 2014 - 11:54 PM.