Question: Don't you think if The big bang thing could explode from something smaller than an atom into the unlimited universe it could have intense amount of heat ?

Ha! Great question. Thats the type of question a scientist would ask.

Now I don’t know how the Big Bang started, or what was around before it happened, but I do know what happened afterwards. I’m sure you do to!

One important thing to remember is that the heat you’re asking about is a type of energy, like sound and motion and light. So before the big bang there was no energy as we know it today. So there was no heat. When the Bang went BOOM, energy was created. All of it!

The next important thing to know is something you might learn in the future if you study Physics. Its called the 1st Law of Thermodynamics and the law says that you cant destroy energy, you can only change what type it is. For example, when a bomb goes off, all the chemical energy saved up in the bomb instantly gets turned into a lot of heat, light and sound energy. So this actually means that when the Big Bang exploded all of the energy that is now in the universe was born at the same time. It’s now in many forms.

Whats most amazing is that there IS still some heat left over from the Bang 13.7 billion years ago! We have a special name for this left over heat and its called ‘Cosmic Microwave Background Radiation’. If you ask @Kyler about this he may be able to tell you even more. But basically, whats left is 2.725 degrees Kelvin, which is the same as saying -270 degrees Celsius (not the best day to go to the beach!)