Planet Earth

And then there was...Earth

• The “Big Bang Theory” is the most widely accepted theory on how the Earth came into being.

• http://vimeo.com/13974273

So how did we go from...

This to This?

Technology!

• In 1922 astronomer Edwin Hubble observed that the universe was expanding.

• Through his telescope he could see that distant galaxies were moving away at 40 000 km/s

Hubble Space Telescope

• New telescopes can see further into space and have determined that galaxies are moving away from Earth at ever increasing rates.

Hubble’s Law

• The velocity at which a galaxy is moving away from us is proportional to the distance of the galaxy from us.

• If the universe is expanding then it is logical to assume that the it was once infinitely smaller.

The Big Bang Theory

• It states that the universe began forming 15 to 20 billion years ago, following an enormous explosion.

• The dust and gas created as a result of the explosion were drawn together by gravitational attraction to form a huge cloud.

The Big Bang Theory

• The debris in this gigantic swirling cloud began to gather in circular movements called eddies.

• The largest eddies contained enough matter to form whole galaxies.

How does this relate to the study of Physical Geography?

Changing Technology

• The Hubble space telescope was originally launched in 1990.

• Over many years scientists have upgraded the telescope with newer technologies.

• This technology has allowed us to map planets, study moons, and observe asteroids and meteorites within our own solar system.

Remote Sensing Tool

• The Hubble space telescope is an example of a remote sensing tool.

• Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object.

Radiometric Dating

• Radiometric dating uses the radioactivity of certain minerals in rocks to determine their ages.

• It was radiometric dating that ascertained that planet Earth is about 4.6 billion years old.