KOMPAS.com Kepler’s 3rd law was proposed by a German astronomer named Johannes Kepler. Kepler’s 3rd law is often referred to as harmonic law. Why is Kepler’s 3rd law called the harmonic law?
Kepler’s 3rd law is called the harmonic law because it describes how the planets harmonize in solar system.
Kepler’s 1st law describes the shape of orbit planet. The 2nd law of Kepler describes the time of the planet’s orbit. That is, Kepler’s 1st and 2nd laws describe the characteristics of a planet.
Meanwhile, Kepler’s 3rd Law does not only explain the characteristics of one planet. Rather it compares the characteristics of the different planets and how the planets in the solar system move and harmonize as they revolve around the sun.
Also read: Kepler’s Laws of Motion in the Solar System
Kepler’s 3rd Law
Kepler’s 3rd law reads:
“The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.”
It is known that the semi-major axis is equal to its average distance from the Sun. Reported from Spacewhat Kepler’s 3rd law actually does is compare the orbital period and radius of one planet’s orbit with that of another planet.
So, Kepler’s 3rd law equation can be written as:
Also read: Why don’t planets collide with each other?
With,
T1: periode planet 1
T2: periode planet 2
r1: planet 1’s average distance from the sun
r2: average distance of planet 2 from the sun
This equation applies to every planet orbiting the sun. According to this equation, the planets with the farthest distance to the sun have long orbital periods and vice versa.
These equations provide a calculation of the planets’ orbits with respect to the sun and an illustration of how the planets in the solar system revolve around the sun without interfering with each other’s orbits.
Reported from Lumen Learning, Kepler sees the planets in the solar system as harmonious “music” and expresses it in equations as well as musical notation. This is why Kepler’s 3rd law is called the harmonic law.
Also read: Newton’s Law of Gravity
Kepler proposed his third law in 1619. At that time, physics and astronomy were not as advanced as they are today. The force of gravity hasn’t even been discovered yet.
Reported from NASA Solar System Exploration, Kepler’s law serve as the basis for an understanding of the dynamics of the solar system and as a stepping stone for new, more accurate theories about the orbit of our planet.
Kepler’s 3rd law does not take into account the mass of the planet. However, when combined with the law of gravity, we can accurately calculate the masses of orbiting planets as well as the orbits of other bodies.
Get updates news of choice and breaking news every day from Kompas.com. Let’s join the Telegram group “Kompas.com News Update”, how to click the link https://t.me/kompascomupdate, then join. You must first install the Telegram application on your cellphone.–
