Science Images: Deputy Dog's Blog - 7 Amazing Holes

All my friends share really cool images, but I don't come across many that would be interesting, scientific, strange and cool. I did today, and I hope you will think they are cool too.

clipped from deputy-dog.com (if you’re expecting filth you’ll be disappointed). looking at photos like these scares and fascinates me in equal doses. the sheer scale of these holes reminds you of just how tiny you are.