Kepler's Laws

Front

What is Kepler's First Law of Planetary Motion?

Back

Planets orbit the Sun in elliptical paths, with the Sun at one of the foci.

Front

What is Kepler's Second Law of Planetary Motion?

Back

A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.

Front

What is Kepler's Third Law of Planetary Motion?

Back

The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.

Front

Define 'ellipse' in the context of planetary orbits.

Back

An ellipse is a closed curve around two points called foci, where the sum of the distances from any point on the curve to the foci is constant.

Front

What are the two foci in an ellipse?

Back

The two fixed points in an ellipse that determine its shape.

Front

What is perihelion?

Back

The point in the orbit of a planet where it is closest to the Sun.

Front

What is aphelion?

Back

The point in the orbit of a planet where it is farthest from the Sun.

Front

How does the speed of a planet change in its orbit?

Back

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 area swept out by a planet in its orbit?

Back

It illustrates Kepler's Second Law, showing that planets cover equal areas in equal times.

Front

What is the relationship between a planet's distance from the Sun and its orbital speed?

Back

The closer a planet is to the Sun, the faster it moves in its orbit.