The universe, began as part of a fireworks display on August 20, called the Big Bang, 13.8 billion years ago. To the sincere delight of series fans, the series has been running ever since, continuously, during prime time. There was no matter, only energy in the form of radiation flowing almost evenly everywhere. It took some time for protons and other elementary particles to form from the quarks, and the young universe had to cool down enough to form the first atoms from these elementary particles: the first atom in the periodic table was born from the marriage of a proton and an electron. : hydrogen .