Where is the Earth placed in the order of the planets?

What objects in space do you know that have astronomical significance? Rank them in size from the smallest to the largest.

What causes the phases of the Moon?

What are the conditions for eclipses of the Sun? the Moon?

What is meant by the "celestial sphere"?

What measurements are made to locate a star or constellation with respect to the celestial sphere?

What is the ecliptic plane? What is its angle with respect to the celestical equator?

What is the origin of the seasons?