Without gravity we would HAVE NO LIVES. For instance, gravity keeps our Earth together; and gravity is an important component in making the Sun produce energy via nuclear fusion.
Helium
The energy which produces light and heat in the Sun comes from "nuclear fusion" deep inside the Sun.
Magic
The sun produces 4 billion kilograms of energy per second..
Fusion produces the Sun's energy .
Nuclear fusion - that is the squeezing together hydrogen molecules in the Sun by the Sun's enormous force of gravity. This process releases a huge amount of heat.
Without gravity we would HAVE NO LIVES. For instance, gravity keeps our Earth together; and gravity is an important component in making the Sun produce energy via nuclear fusion.
heat
vibrations produces wave
You can indeed get energy from gravitational contraction. However, theoretical calculations show that this type of energy can in no way power the Sun for 4.6 billions of years - and it is known that Earth, and the Solar System, have approximately that age.
The Sun.
Helium
A sun.
Gravity.
Yes, the sun is a source of radiant energy. The light the sun produces is radiant energy.
The energy which produces light and heat in the Sun comes from "nuclear fusion" deep inside the Sun.