Front

What is Kepler's First Law?

Back

Planets travel in an ellipse with the Sun at one focus.

Front

What is the term for the point at which the Earth is closest to the sun?

Back

Perihelion.

Front

What is the term for half of the major axis of an ellipse?

Back

Semimajor axis.

Front

According to Kepler's Second Law, how does a planet's speed change as it orbits the Sun?

Back

A planet moves faster when it is closer to the Sun.

Front

Which ellipse has the lowest eccentricity?

Back

The ellipse that is most circular.

Front

What is Kepler's Third Law?

Back

The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit (p^2 = a^3).

Front

Define eccentricity in the context of an ellipse.

Back

Eccentricity is a measure of how much an ellipse deviates from being circular.

Front

What does it mean for a planet to sweep out equal areas in equal times?

Back

It means that a planet moves faster when it is closer to the Sun and slower when it is farther away.

Front

What is the significance of the major axis in an ellipse?

Back

The major axis is the longest diameter of the ellipse, passing through both foci.

Front

What is the term for the point at which the Earth is farthest from the sun?

Back

Aphelion.