Macksville's Irwin Partridge was taking photos at Main Beach, Nambucca Heads, on June 2 - and didn't realise what he captured until he downloaded his images onto his computer.
Irwin was amazed to see a small dark circular speck in the sky.
He has no idea what it could be - and neither do we.
The picture has been circulating on Facebook, and there are plenty of theories.
What do you think it is?