Astolot Educational Centre – Alisa Miller – SNC1P

4.15 The Origin of the Universe -The study of the origin and changes of the universe is called cosmology The Big Bang Theory -If the galaxies are moving apart, then they used to be closer together -“Time zero” is when the galaxies were next to each other -Scientists have estimated that time zero was 10 billion to 15 billion years ago -At that time, all the matter of the entire universe was packed together into one small, extremely dense, hot mass under enormous pressure -The event where this mass began to move apart is called the Big Bang -Scientists use the Big Bang Theory to describe the beginning of the universe that we know -Red shift supports the Big Bang -Scientists have collected data that suggest that the universe is still “glowing” from that initial bang ! just like a match that continues to glow after the flame has been put out -The Big Bang Theory can be used to explain why the universe is expanding, but we still have a few questions -Scientists know what the universe looked like a millionth of a second after the Big Bang, but they don’t know what it looked like a millionth of a second before the Big Bang -For this reason, theories about the origin of the universe are probably going to be refined and reworked The Origin of the Solar System -If the Big Bang explains how the universe began, what explains the formation of the solar system? -In its early stages, our solar system was part of a nebula

Astolot Educational Centre – Alisa Miller – SNC1P

-A nebula is a spinning mass of gas and dust -All stars are born from nebulas -Gravity causes the matter of the nebula, the clouds of gas and dust, to spin together -The gas and dust in the centre become a star and the rest of the matter is pulled together by gravity to form the planets. Homework: Read 4.15 The Origin of the Universe, Pg. 226 – 227 Pg. 227 #1,4,6