In our Sun, hydrogen atoms are fused (squeezed together) to create helium atoms.  This is called nuclear fusion, and it produces the Sun's energy.

1.  What appears to be wrong with the nuclear fusion equation on the top right?

2.  What is actually missing from the equation?

3.  E = mc² is a famous equation.  What do each of the letters in the equation represent?

4.  Can you guess the difference between nuclear fusion and nuclear fission?