Volcanoes of various types are found on other planets and their moons as well as on earth.

Volcanoes are said to be active, dormant or extinct. This has to do with how often they erupt. Those that erupt often are called active. Those that have erupted during historical times but are now quiet are called dormant. Those that have not erupted since man has kept records are called extinct.

A great place to get up close and personal to a volcano is the big island of Hawaii. Professor Nibble has seen lava flow into the sea just yards from where he was standing. He also looked down into a cauldra and saw red hot lava bubbling. It was so hot that my face turned bright red.

Scientists study Mauna Loa because it is not as dangerous as other volcanoes. Don't get me wrong. All volcanoes are dangerous and people sometimes die when they erupt. You wouldn't want to be anywhere around during a major eruption of Mauna Loa.