Astronomy cha1

1. The seasons on Earth are linked to equinoxes and solstices. Define these terms in relation to what they mean to our seasons, and describe them in relation to the celestial equatorial plane and the plane of the ecliptic.

2. In your own words, state Kepler’s three laws.

3. The three units of distance used in astronomy are the Astronomical Unit (AU), the Light Year (LY), and the Parsec (pc).

Define AU in terms of kilometers:

Define light year in terms of AU:

Define parsec in terms of light years:

4. (a) Explain what would happen to a planet’s motion if suddenly all gravitational forces ceased to exist. Relate your explanation to Newton’s 1st and 2nd Laws.

(b) State Newton’s Law of Universal Gravitation