The EarthMoon System

1
The Earth-Moon System

• The Tools of Astronomers
• Lesson 1

2
What is Astronomy?

• The branch of science that deals with whats up
  there
• Astronomy is the study of the universe.
• An astronomer is someone who observes the
  universe and tries to explain what is observed.

3
Universe

• The universe is everything that exists-
• Earth and all the things in space.
• Space planets, stars, galaxies.

4
Observing the Universe

• One method is to use the eyes.
• A second method is using a telescope.
• A telescope is a device that collects light.
• Another method is using robots or satellites.
• Models are a way of simplifying the world so that
  we can understand it better.

5
What is Light?

• Light is also called electromagnetic radiation,
  or electromagnetic waves.
• Radio waves, infrared waves, ultraviolet waves, X
  rays, gamma waves.
• Light travels at a speed of 300,000 kilometers
  per second(186,000 miles per second).
• The Sun is so far away that it takes eight
  minutes to travel from the Sun to Earth.

6
Light is a Wave

• Refraction means the bending of the waves as
  they go from one substance to another.
• Refraction is also the basis of eyeglasses and
  some telescopes.

• Reflection means the bouncing of waves off a
  surface.
• Mirrors and some telescopes use this property of
  light.

7
How Do Telescopes Work?

• Two types of telescopes.
• A reflecting telescope uses a mirror and a lens
  to form and magnify an image
• A refracting telescope uses lenses to form and
  magnify an image.

8
How Do We Get Information From Space

• When you see objects through a telescope, you are
  looking through Earths atmosphere.
• Scientists send artificial satellites into orbit
  high above the Earths atmosphere.
• Space probes travel away from Earth.
• They take photographs and perform experiments.

9
Earth Orbiting Satellites

• Weather satellites track hurricanes and other
  large storms.
• Communications satellites allow us to see
  television pictures from around the world.
• Space shuttle astronauts launched a special
  telescope called the Hubble Space Telescope.