Astronomy and Our Origins

Where did we come from? Scientists believe the entire universe began as a single, one dimensional speck that exploded into existence. This idea is called the Big Bang Theory! Do we know for sure…of course not…we could be right or wrong. We will never know. But we do have a lot of evidence to support our hypothesis.

That explosion caused everything in the universe to spread apart and speed away from each other. This spreading apart is occurring today and can be measured. If we wind the clock backwards, we believe the age of the universe to be 13.7 billion years old.

Doppler Effect = the change in frequency emitted from a moving object. For moving sound sources (race cars, sirens, etc) the pitch (highness/lowness) changes. For moving light sources (stars, galaxies, etc) the light color changes.

Doppler Effect Things moving away shift to Redder colors = longer distances & longer wavelengths = red shift Things moving towards us shift to Bluer colors = shorter distances & shorter wavelengths = blue shift

Countless stars formed, lived and exploded a violent death, spewing their guts into the universe.

This is an actual star explosion that occurred in 1054

Eventually gravity caused a section of all this left over star material to spin, clump together and form the sun, planets, and our whole solar system. This process is called the nebular hypothesis. Everything in space spins and moves in lots of different ways. Earth’s motions include rotation, revolution, and precession, and others.

Formation of our solar system nebula

Nebula