iceberg mystery, “cable stab”

This NASA photo in Antarctica has fascinated not a few people. Iceberg's a regular rectangular, like stabbed.

We all know that nature is not perfect, it doesn't make things like ruler. Yet, this phenomenon is natural. He hasn't cut off an alien.

Perfect icebergs have happened before, and they take their form when they break away from another mass.

Scientists compare it to a fingernail that if you let it grow, one day it can be cut itself with very straight cuts.