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Intro to Astronomy

• Terms You Need To Know!

1. Astronomy-
The study of everything outside of the earths
atmosphere.
2. Celestial Sphere -
Imaginary sphere that surrounds Earth, in which
all stars, planets and moons are attached to.
3. Zenith Point -
The point directly above you in the sky.
4. Nadir Point -
The point directly below in the sky.
When an object is moving, the apparent motion you
see when close objects move faster than far away
objects.
5. Parallax -
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• 6. Rotation -

An object spinning on its axis.

• 7. Revolution -

One object orbiting around another object.

• 8. Geocentric Universe -

Earth centered universe.

• 9. Heliocentric Universe -

Sun centered universe.

• 10. AU -

The distance from the Earth to the Sun.
93,000,000 million miles
History of Astronomy

• A. Geocentric People

• 1. Plato

- Planetary objects moved in God Paths
- Aristotle was his student.
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• 2. Aristotle

• Said the Earth didnt move because he did not
  see parallax with the stars in the sky.

B. Heliocentric People

• 1. Copernicus

- One of the first people to teach the
heliocentric universe model.
- The Church let him go because he was working on
calendar reform.

• 2. Tycho Brahe

- Studied the positions of many planets and stars.
- Discovered the sky changed when he found a
comet in the sky.
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• 3. Kepler

- Helped Tycho Brahe with mathematics.
- Discovered the 3 Laws of Planetary Motion.

• 4. Galileo

- Invented the telescope.
- Discovered moons revolving around Jupiter.

• 5. Newton

- Discovered the Laws of Gravity.
- Discovered the 3 Laws of Motion.
- Proved the heliocentric universe model.