You could never pick up this snowball in your hands. It measures almost three miles across!

This snowball is one of God’s creations you might never see in person—at least in this lifetime. It is a comet. Comets are made of ice and dust. They orbit the sun. In a report released on July 1, scientists said they discovered something new: Comets, like Earth, have sinkholes.

The scientists studied a comet called 67P/Churyumov–Gerasimenko. It has 18 large holes on the surface. Sinkholes happen when the ground suddenly opens up. As time passes, the pits grow bigger and bigger. That means the pits might be able to tell scientists how old the comet is.