Gravity and the Universe

Define Gravity

What is a nebula?

Define galaxies

Galileo was best known for . . .

• Being name dropped in a Queen song

• Sitting under an apple tree

• Inventing the telescope

What was Johannes Kepler's discovery?

• The the planets orbit the sun in ellipses not circles.

• The planets orbit the sun every 365 days.

• The planets orbit the sun in perfect circles.

• Each planet has a oval orbit.

What holds galaxies together?

• Gravity, duh.

• The power of friendship.

• Magnetism

Why do planets orbit the sun?

• Because it is a star.

• The sun is less massive than the planets.

• The sun is more massive than the planets.

• Because it generates its own light.

What is a group of galaxies called?

• Group

• Pod

• Bunch

• Cluster

Spiral Galaxy Characteristics

• Arms that begin at central disk, thick center, red stars surrounding disk

• No arms, high % of old red stars, little to no gas, formed from two or more other types of galaxies merging

• Oddly shaped, formed from gravitational pull of other galaxies, contain young stars, areas of intense star formation

True or False: Galaxies are unequally distributed.

• True

• False