CELLS-ORIGINS

Origin of the Earth and Life |

Scientific estimates place the origin of the Universe at between 10 and 20 billion years ago. The theory currently with the most acceptance is the Big Bang Theory, the idea that all matter in the Universe existed in a cosmic egg (smaller than the size of a modern hydrogen atom) that exploded, forming the Universe. Recent discoveries from the Space Telescope and other devices suggest this theory smay need some modification. Evidence for the Big Bang includes:

1) The Red Shift: when stars/galaxies are moving away from us the energy they emit is shifted to the red side of the visible-light spectrum. Those moving towards us are shifted to the violet side. This shift is an example of the Doppler effect. Similar effects are observed when listening to a train whistle-- it will sound higher (shorter wavelengths) approaching and lower (longer wavelengths) as it moves away. Likewise red wavelengths are longer than violet ones. Most galaxies appear to be moving away from ours.