Kepler’s 3rd Law is sometimes called The Law of Periods: The square of the period of any planet is proportional to the cube of the semimajor axis of its orbit. In this video, we derive Kepler’s Third Law from Newton’s Law of Gravitation. We also show you how to use this law to determine the orbit of Mars around the Sun. Finally, we apply Kepler’s Third law to the Moon’s orbit around the Earth, using it to calculate the mass of the Earth.

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Kepler’s 3rd Law is sometimes called The Law of Periods: The square of the period of any planet is proportional to the cube of the semimajor axis of its orbit. In this video, we derive Kepler’s Third Law from Newton’s Law of Gravitation. We also show you how to use this law to determine the orbit of Mars around the Sun. Finally, we apply Kepler’s Third law to the Moon’s orbit around the Earth, using it to calculate the mass of the Earth.

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Course Description

Come with us as we explore our Universe! Learn about various celestial bodies including Neutron Stars, White Dwarfs, Black Holes, and more. We visit Mars, and explain the phenomenon of Earthshine. You will even learn all three of Kepler's Laws.