Space

Unit 1 (Unit 4 in textbook)

Celestial BodiesNatural bodies in space such as…

Comets

Moons

Stars

Planets

Asteroids

How do celestial bodies move?

• Planets, suns and moons rotate on a central axis:

How do celestial bodies move?• Celestial bodies move in orbits caused by

gravitational forces:

Constellations• Patterns of stars are called constellations• Constellations are based on Greek mythology

(and lots of imagination)• For example:– Ursa Major (Big Bear)

Constellations

• Ursa Minor (Little Bear)

Constellations

• Orion (the Hunter)

Constellations

• Cassiopeia (the Queen)

Constellations

• Leo (the Lion)

Constellations

• Asterisms, such as the Big Dipper, are groups of stars forming patterns within a constellation

Constellations• Constellations in our north sky which never go below

the horizon are called circumpolar constellations.

http://www.youtube.com/watch?v=3V3rmDG5J8A&feature=related

Examples:

Ursa MinorUrsa MajorCassiopeiaDraco

Zodiacal Constellations• Zodiacal constellations are the 12 constellations that lie on the

sun’s ecliptic(the ecliptic is the path through the sky that the sun appears to follow each day)

Your “sign” is determined by the constellation that was on the other side of the sun when you were born...

Seasonal Constellations

• Because earth moves around the Sun every year, we see a different part of the sky (and different constellations!!) during each season

Orbits• All the planets and asteroids in our solar system

seem to orbit on the same plane• Comets are an exception and can orbit above or

below the ecliptic