Centripetal Acceleration In Moon: 7 Facts You Should Know

Centripetal acceleration is defined as the equity of the movement of the gadget, crisscrossing a circular path. Any gadget traveling in a circle with an acceleration vector peaked concerning the center of that circle is called centripetal acceleration.

Centripetal acceleration on Moon is described as “the Moon is to move faster in the direction of the Earth through a diameter from Earth to the Moon. The acceleration desired to retain the gadget (there is the Moon here) proceed throughout a circle is called the centripetal acceleration. Centripetal acceleration is always at right angles to the gadget’s travel”.

Is centripetal acceleration exists on Moon?

Yes, centripetal acceleration exists on Moon. The gravitational attraction between the Earth and the Moon holds the Moon in a loop regarding the Earth. In this case, we can employ centripetal force to the force of attraction, but the centripetal force is not an abstracted force retaining gadgets traveling in a circle.

The Moon spinning around the Earth in a circular loop is captured by the gravitational force of the Earth employed on the Moon. Gravitational force never works on the Moon because the centripetal force is vertical to motion supervision every time. Hence work is not done.

 Let us suppose that the mass of the Moon is about 1.2% of the mass of the Earth. As opposed to the gravitational force employed on the Moon, the gravitational force that Earth employed on the Moon is identical to the gravitational force the Moon employed on Earth.

Fgravitation=GMm/R2 expresses the gravitational force. Where M and M are the masses of celestial bodies and R is the separation between them. M and m equal force is stand-in on the two masses, F=GMm/R2

Centripetal acceleration in moon
Centripetal acceleration in Moon image credit: pixabay

Why does centripetal acceleration exist on Moon?

Centripetal acceleration exists in the Moon because of the gravitational force employed on the Moon by the Earth. Moon is spinning about the Earth in a relatively uniform circular motion. This movement of the Moon is attainable because of gravitational force on the Moon furnishes the required centripetal acceleration to stay in orbit.

The Moon is rotating over the Earth caused by the centripetal force. Each circular motion enforces centripetal force. In the case of the Moon, attraction or gravity is the centripetal force. If we have a rotating top, then the intramural pressure from molecular bonds would supply the centripetal force.

The Moon does not just drop in because gravity’s force is transverse every time to the velocity, so it varies its supervision. It is the estimation, however, because the Earth and Moon have been supposed to be point masses and the orbit to be entirely spherical. Gravity brings both the Earth and Moon to deform moderately.

Centripetal acceleration in moon
Spinning of Moon around the Earth image credit: pixabay

Do the Moon and Earth have the same acceleration?

No, the Moon and Earth do not have the same acceleration. 

The Moon is accelerating more than the Earth because the Earth’s gravity retains the Moon encircling us. It retains varying the supervision of the Moon’s velocity. It means gravity assembles the Moon to accelerate all the time. However, its speed stayed constant.

The Moon’s exterior gravity is about 1/6th as strong or about 1.6 meters per second. The Moon’s outward gravity is robust because it is vastly lighter than Earth. A body’s exterior gravity corresponds to its mass but reciprocally corresponds to the square of its radius.

The Moon arrives to be driving appreciably more advanced than the Earth abruptly at the same time, so hence has to be traveling faster. The same force portrayed on dissimilar masses will generate acceleration oppositely proportional to the mass, so the 80 times extra massive earth is accelerated 80 times smaller than the Moon and should travel about a path.

Centripetal acceleration in moon
Outward gravity of the Moon is vastly greater than the Earth image credit: pixabay

How is centripetal acceleration on Moon different from the Earth?

The centripetal acceleration is represented by a= v2/r, and this expression relies on the Moon’s speed which is nilpotent am is Moon’s centripetal acceleration due to the gravitational attraction of the Earth, ω is the radial velocity, Rm is the bifurcation between the Earth and Moon, which is 60 assets the diameter of the Earth. 

Let me take the example of centripetal acceleration on the Moon; to find out the Moon’s centripetal acceleration as it orbits around the Earth, we should determine the frequency of the orbit. We can then utilize the frequency to enumerate the magnitude of velocity. An example of centripetal acceleration in the Earth is if we operate a car around a circle, our car experiences centripetal acceleration.

The centripetal acceleration of the moon is v2/r = 2.725*10-3m/s2.Whereas the centripetal acceleration of the Earth is about 0.03m/s2 . Earth’s period of gyration is an astronomical day, and the tropical radius of the Earth is around 6378 km.

Free illustrations of Solar system
Moon’s centripetal acceleration as it orbits around the Earth image credit: pixabay

Calculate the magnitude of centripetal acceleration on the Moon?

To retain the gadget in a circle, centripetal acceleration should draw the gadget against the circle’s center. Stare at the Moon circling earth in the following figure. The Moon is accelerated concerning the Earth across a radius from Earth to the Moon.

Moon circling the Earth

The centripetal acceleration is always perpendicular to the gadget’s moving, and its acceleration peaked against the circle’s center. Centripetal acceleration ac has a magnitude equal to the square of the velocity of the body v through the orbit partition by the bifurcation r from the circle having the center to the moving body; which is,

ac= v2/r

 The horizontal velocity v of the gadget moving close to the circle is squarely linked to the radial velocity. i.e v= ω×r. So, we can also write the above equation as

ac = v2/r=r)2/r = ω2r

Example question

Given that the Moon travels around Earth about every 27.3 days and its separation from the center of Earth is 3.85×108m, what is the Moon’s centripetal acceleration?

The magnitude of the centripetal acceleration is given by


The separation the moon moves in 27.3 days is d= 2πr = 2.41*109m.

We have to find the speed of the moon so convert 27.3 to seconds

v= d/(27.3days) = (d/(2.36*106s))

Hence, the Speed of the moon is 

The centripetal acceleration of the moon is v2/r=

Calculate the centripetal acceleration of the Moon towards the Earth?

a = v2/r gives the centripetal acceleration.

This expression relies on Moon’s speed which is decidable. Let us work with the formula

Ɛ Rm = am

am is the centripetal acceleration of the Moon due to the gravity of the Earth.

Rm = 604 =60× 6.4× 106

= 384 ×106m

As we know, the angular velocity

And T= 27.3 days = 27.3 × 24 × 60 × 60 second = 2.358 ×106 s

By substituting above mentioned values in the formula for acceleration 

am =

am = 0.00272m/s2

The centripetal acceleration of the Moon towards the Earth is = 0.00272 m/s.

What would happen if there was no centripetal acceleration on the Moon?

  Moreover, the Moon is rotating about the Earth in an oblique motion because of the centripetal acceleration turned over. In the omission of centripetal force, the Moon will not be capable of attending a circular path and would travel in a straight line diverging to the orbit of the Moon.

If no centripetal force is acting on the Moon, then the Moon will travel linearly rather than spin around the Earth. Without centripetal force, the Moon should never modify its supervision. It is mandatory to have a centripetal force to preserve a circular motion.

Hence it is reverse to the supervision of gravity at the equator; at the Earth’s beams, it is zero. The centripetal force is the mandatory internal force that retains the mass from traveling in a straight line; it is similar in size to centrifugal force but with the reverse sign.


From reading above mentioned fact, we finally concluded that when the Moon has come across uniform circular motion, the acceleration of the Moon and the force required to control the motion have definite associations. The centripetal acceleration has a straight association with the square of the acceleration of the Moon.

Megha BR

Hi, I am Megha B R, I have completed my Post-Graduation in Solid State Physics and pursuing B. Ed. I am a Physics enthusiast. As an Academic writer, my goal is to reach the readers in a simplified manner through my articles. Let's connect through LinkedIn-https://www.linkedin.com/in/megha-br-08a129206

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