What's hiding behind these giant holes on the Moon?

You've probably seen the mysterious giant hole that was discovered in Siberia, which appears to lead into a large cave. We don't know its origin yet, but it isn't the only hole like that on Earth. Or the Moon: NASA found these formations there too, which are perfect for future human outposts. Or current alien/Nazi UFO… » 7/17/14 8:04pm 7/17/14 8:04pm

No One Knows Why Deep, Dangerous Holes Are Appearing In This Sand Dune

One summer day last July, a six-year-old boy was walking across a dune when he disappeared, falling into a deep, narrow hole in the sand. This and two other holes that have since appeared at Indiana's Mount Baldy are unlike anything scientists have seen before—it could be an entirely new geological phenomenon. » 4/28/14 6:30pm 4/28/14 6:30pm