Planetary Motion

What is the name of the shape that planets orbit the sun in?

• Circle

• Eclipse

• Square

• Ellipse

What are the two center points of an ellipse called?

• Orbits

• Foci

• Midpoints

• Major axis

How many foci are in a circular orbit?

• 1

• 2

• 3

• 4

What is the orbital period of a planet?

• The distance from one side of its orbit to the other

• The time it takes to rotate once on its axis

• The distance around its entire orbit

• The time it takes to revolve around the sun

What is the eccentricity of this shape?

• 0

• about .25

• about .5

• 1

What is the eccentricity of this shape?

• 0

• about .25

• about .5

• 1

As the distance away from the sun increases, how does a planet's orbital velocity change?

• It increases

• It decreases

• It stays the same

As the distance away from the sun decreases, how does a planet's orbital velocity change?

• It increases

• It decreases

• It stays the same

What is the point on a planet's orbit where it is furthest away from the sun called?

• Perihelion

• Aphelion

• Apogee

• Perigee

What is the point on a planet's orbit where it is closest to the sun called?

• Perihelion

• Aphelion

• Apogee

• Perigee