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all about astronomy
Hi. I'm the voice in your head you hear when you read. How's everything going? This is the Standard Deviants' guide to astronomy. It covers everything in the episode of Standard Deviants Television: Astronomy, and a little bit extra…
Click here to review everything covered in this episode of Standard Deviants TV. go!
time codes
  1. Introduction- 1:01:15
    1. The History of Astronomy- 1:02:10
      1. Pythagoras- 1:02:30
      2. Geocentric model- 1:02:49
      3. The Celestial Sphere - 1:03:10
      4. Aristotle- 1:04:30
      5. Stellar parallax- 1:05:05
      6. Ptolemy- 1:06:47
      7. Retrograde motion- 1:07::13
    2. The Copernican Revolution- 1:10:01
      1. Heliocentric model- 1:10:08
      2. Tycho Brahe- 1:11:45
    3. Kepler's Laws- 1:13:05
    4. Galileo- 1:17:28
    5. Newton- 1:20:18
      1. Law of gravitation- 1:21:58
      2. Laws of motion- 1:22:48
discussionPoints
1. What are some ways you can think of proving that the Earth is round?

2. Why did Aristotle think that the Earth was immobile and the heavens revolved around it? Was he being irrational?

3. Why didn't the church seem to care when Copernicus announced his belief in a heliocentric solar system? Why did they criticize Galileo but almost ignore Copernicus?

4. How did the telescope change astronomy?

5. How does Newton's law of gravity differ from Kepler's second law?

activities
How to Make Rainbow Colors

Materials:
• A small mirror
• A piece of white paper
• A large baking pan (any shallow container will do)

What to do:

1. Fill the baking pan about 2/3 full with water. Place the pan outside.

2. Hold your mirror in the water and tilt it so it is facing the sun (or tilt it towards yourself, you cute devil).

3. Reflect the light from the mirror onto the paper. Voilą! You should be able to see the whole visible spectrum.

How's it work?

Have you ever heard the term "white light" before? Don't let the term fool you. White light isn't a single color of light. It's the light you get when you mix all the colors of visible light together: red, orange, yellow, green, blue, and violet.

The light that comes out of the sun is white light. So, what we did in this experiment was separate the white light from the sun into all the colors that make it up.

When light passes from one medium to another (like from air to water), it bends. This is called refraction. You can see this for yourself by putting a straw in a glass of water. See how the straw shifts when it enters the water? That's from the light bending as it enters the water.

The thing is, each color of light refracts in slightly different ways. For example, red light bends less than blue light. So when the water refracted the sunlight and it bounced off the mirror, all the colors of light bounced off at slightly different angles, making the spectrum that you saw.

Astronomers can examine the visible light a celestial object gives off to learn valuable clues about its chemical composition. What's cool is how much info scientists can get from an object's visible light.

What's even cooler is that visible light makes up only 1/1000 of the total light spectrum. Most of light is invisible, like gamma rays, x-rays, and radio waves. And scientists have a whole bag of tricks to get information from an object's invisible light as well.

testKnowledge
Click here to go to the test.

astronomy

purchase

did you know?
Telescope actually means "light bucket." So a big telescope is a heavy light bucket.
 
vocabulary
Astronomy—Astronomy is the study of everything that lies beyond the Earth's atmosphere.

AU—Astronomical Unit. One AU is equal to the length of the Earth's semi-major axis.

celestial sphere—An imaginary sphere around the Earth that all the stars and planets are placed on.

meridian—A circle on the celestial sphere that passes through the two poles and the zenith of your position.

nadir—The point on the celestial sphere directly opposite the zenith and underneath your feet.

zenith—The point on the celestial sphere directly above your head.

geocentric universe—A model of the universe with the Earth at the center.

heliocentric solar system—A model of the universe with the sun at the center.

ion—An atom that has lost or gained electrons.

Kepler's laws—Three laws of planetary motion based on the observation that planets orbit the sun in ellipses.

Law one—The orbits of planets are ellipses, with the sun at one focus.

Law two—An imaginary line from a planet to the sun will sweep over equal areas of the ellipse in equal intervals of time.

Law three— A planet's period squared is proportional to a3. A is the length of a planet's semi-major axis.

Newton's law of gravitation—The force of gravity between any two objects in the universe is equal to the mass of the first object (m1), multiplied by the mass of the second object (m2), multiplied by a gravitational constant (G), all divided by the square of the distance between the two objects.

Newton's laws of motion—Three laws of motion that give a more fundamental understanding of the universe than Kepler's laws.

Law one— All objects at rest stay at rest. All objects in motion stay in motion, in a straight line and at a constant speed, unless acted upon by a force.

Law two— Force equals mass times acceleration, or F = m x a.

Law three— For every force one body exerts on a second body, the second exerts an equal and opposite force on the first.

period—The amount of time (in Earth years) it takes a planet to orbit the sun once.

right-hand rule—A rule to help you determine which way is north on a planet. Point your fingers in the direction the planet rotates. Your fingers should curl around the planet, like you are grabbing a ball. Then stick out your thumb. That way is north.

retrograde motion—Backwards (westwards) motion of a planet with respect to the stars.

revolutional period—The length of time is takes a planet or moon to cycle around the object that it orbits. Earth's revolutional period is 365 days.

rotational period—The length of time it takes a planet or moon to rotate 360 degrees on its axis. Earth's rotational period is 24 hours.

semi-major axis—Half the length of the longest diameter of an ellipse.

spectrum—The range of visible light: red, orange, yellow, green, blue, indigo, and violet.

stellar parallax—The apparent motion of an object due to the change of the location of the viewer.

 
resources
Explore the universe by checking out some cool astronomy-related websites. Remember, you will be leaving the Standard Deviants TV website. Enjoy!
Related Sites

This is a cool NASA website just for kids!

Here's a great NASA resource for teachers and parents.

Like the pictures from the Hubble telescope? Check out this site for lots of great images.

    
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