Thanks to David Sproule who sent me this photograph

He wrote

I'm attaching a couple of photos, that you may want to use for your site, and also I'd like your opinion on the them. I believe that they are "whistle-blowing" props, but maybe they are naturally occurring on the moon.( YEAH RIGHT)

My reply

Well I never! An alien skull on the moon surface or whistle blowing props on a conspiracy film set or maybe just a rock formation that we think looks like a strange skull. I think the latter because if you think about it we can even see a "man in the moon" i.e. facial features that are really something else i.e. mountains and plains.

N.B. It's only people in the Northern hemisphere who see a "man in the moon". It looks completely different in the Southern hemisphere. Unless you're stood on your head, that is !