Origin of the Planets and Universe

(page 478 and 479 of text 15.5)Big Bang

The Big Bangby the Barenaked Ladies

http://www.youtube.com/watch?v=lhTSfOZUNLo

CosmologyCosmology is the study of the origins,

creation, and changes of the planets, Sun, and Universe.

Theories how the Universe was created:

• Big Bang• Origin of the Planets• Intelligent Design• Steady State• Oscillation Theory

The Big Bang

The Big Bang Theory is the dominant scientific theory about the origin of the universe.

According to the big bang, the universe was created sometime between 10 billion and 15 billion years ago from a cosmic explosion that hurled matter and in all directions. (figure 1 page 478)

Big Bang

Time Zero – is estimated to be between 10 and 15 billion years ago.

At this time, all the matter of the entire universe was packed together into one, small extremely dense, hot mass under enormous pressure.

Thus, the BIG BANG

Red Shift

Evidence suggests the Red Shift of distant galaxies contributes to the theory of the Big Bang.

The red shift is a movement toward the red end of the spectrum.

http://www.youtube.com/watch?v=FhfnqboacV0

Origin of the Planets

• Estimated about 4.6 billion years ago.

• Sun formed from a nebula.• 4 terrestrial planets formed from left

over dust from our Sun’s original nebula.

• 4 gaseous planets formed from left over gases from our Sun’s original nebula.

(nebula: a huge cloud of dust and gases in outer space; the beginning and ending of a star)

Intelligent Design

The belief that humans, life, the Earth, and the universe were created by a supreme being or Deity's supernatural intervention.

Steady State

The steady state theory asserts that although the universe is expanding, it nevertheless does not change its look over time. For this to work, new matter must be formed to keep the density equal over time.

Oscillation Theory

This is nothing more than a recurring Big Bang every 80 billion years. Each explosion begins a new cycle that ends with another explosion.

p. 479 question 1

1. How does the Big Bang theory explain an expanding universe?

The big bang theory extends our current observations back in time several billion years.

If our universe is expanding, then at some time in the past, the stars, galaxies, and other objects in the universe must have been closer together.

A very long time ago, all these objects must have been part of some incredibly dense, massive object that exploded (the Big Bang), then expanded outward.

The explosion must have had enough energy to allow the expansion to continue, even now.