I watched a bunch of Bill Nye videos. I watched about volcanoes, geysers and gravity.
Let’s start with volcanoes, volcanoes contain magma. Magma is made of melted rock from the Mantle. Magma comes out of a volcano when it erupts. The magma cools down and turns back to solid rock. Open volcanoes release magma when it erupts. Closed volcanoes release poisonous gas when it erupts.
A geyser is almost the same as a volcano only it spits out boiling hot water. The water is coming from an underground water source. it is heated by the earth’s mantle and when enough pressure is built it spits it upwards.
Gravity is a force that pulls everything to the center of the earth. Gravity was discovered by Galileo Galilei. He tested the theory be dropping a cannon ball and an apple from the top of the tower of Pisa. The cannon ball and the apple hit the ground at the same time.