Astronomy
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A. Facts

Terran diameter: 12,756km (<8000miles) radius = 6,371,000m
Lunar diameter: 3500km (earth/4)
Earth mass:
Moon mass: 0.01 X Mass of Earth
Moon's Average distance: 384,400km (250,000 miles) from Earth
Age:
Orbits because of:
Moon orbits around Earth:
Moon rotates:
Earth Atmosphere:
Moon Atmosphere:
Gravity on Earth:
Gravity on Moon:

B. Gravity (Newton & Einstein)

  1. Galileo discovered/proved that Objects on Earth all fall at the same rate. g = -9.81m/s2
  2. DesCartes & Kepler each had their own theories about planetary motion. Kepler figured out their true paths, but they were otherwise both wrong about gravity.
  3. Newton wrote equation to calculate gravitational force between and 2 obj. He figured out that gravity and inertia keep them in orbit.
Newton's Law of Universal Gravitation (p263):
where G is the constant of universal gravitation,
the m's are the masses of the 2 objects, and r is the distance between them.
Force is measured in Newtons
Gravitational force is localized to the center of a spherical mass. (so to find your weight, we would need to know the radius and mass of the Earth.)
4. Einstein found the link between mass, gravity, velocity and time. Mass curves time-space, causing objects to fall into gravity wells.

C. Tides - We travel through 2 zones of high tides a day, because there are 2 tidal bulges that follow the Moon as the Earth rotates below it.

  1. Spring Tides-
  2. Neap Tides-

D.Phases- 4 weeks, 8 phases position, West to East, orbit, Sun, Moon, Earth light, shadow, visible parts, reflection, rotation speed, ecliptic, The near side of the Moon is always turned toward the Earth. Position of Moon changes as goes around ---- in its orbit... causes different phases at different times. We only see part of the Moon that the Sun is shining on it.

(The moon has 8 phase positions that re-occur every four weeks. The phases of the moon are caused by it rotation (revolutions) around the earth, and the amount of light that is shown onto it. During the moon's orbit, we can only see a piece of the part of the moon that is illuminated. The moon follows the ecliptic, it rises in the west and sets in the east. The near side of the moon is always facing the earth, which shows each phase. The earth sometimes casts a shadow (eclipse) on the moon.)

Leeson's Animation that will probably never get finished.


The Teacher


E. Eclipses

1. Solar Eclipses-
2. Lunar Eclipse-
	Why do they last so long?
Define Umbra, Penumbra, Partial eclipse

F. Theories concerning the Origin of Luna

  1. Sister world formed at the same time of the same stuff (popular, but moon has no iron core)
  2. Parted at birth (“)
  3. Parted because of a collision much later (but could Earth have healed the wound?)
  4. Captured (but moon has similar water isotope content)

G. Why is the Moon so important to humans?

  1. Romance / Religion / Our closest neighbor, it is somehow our connection to the cosmos
  2. Science
  3. Exploration
  4. New Territory to conquer and rule, bwa-ha-ha-ha-haaaaaaaaaaaaa!
  5. Launching platform / staging area / practice for exploring other places:
    1. gives a 2300mph boost to speed when launching from moon as opposed to earth
    2. lesser gravity means it's easier to escape
    3. let's use moon materials instead of earth materials!!!
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