Lenticular cloud sunset over extinct volcano, Patagonia, Argentina (@ David H. Collier/Getty Images)
- Is this some sort of bizarre inverted tornado?""Or just a really cool cloud?
- These formations are often called “saucer clouds.\"""Can you spot any sign of alien life?
- You\re most likely to see these near mountains.""Where did this one appear?
- You don\t have to journey to South America to witness this sort of sensational sky.""Occasionally it happens much closer to home