“Gravity” is a kind of force. This gravity is the massive stars force, The force that pulls other objects from the planets to their centers. In theory, all objects with mass have gravity, but the gravitational force they exert is so weak that it can only be seen significantly in massive objects such as planets and black holes.
This gravity is the force that keeps the stars in the galaxy together. In the same way, let the planets revolve around the stars. It is this gravity that keeps the moons orbiting the planets.
If a person on Earth jumps, why doesn’t he fly out into space and fall back to the ground? If you throw things up, why do they fall back down?
The answer is “gravity”. It is an invisible force that pulls objects together. If you jump, you fall back. If you lift things up, they fall back because of gravity.
Everything that has mass has gravity. The greater the mass, the greater the force of gravity. Also, gravity weakens with distance. The further away, the less gravity there is. If you think about it another way, the closer two objects are to each other, the greater the gravitational force between them.
Earth’s gravity is the sum of all the mass it contains. All the mass it contains combines to form a gravitational field. Because of this gravity, in our world, “Weight” appears in animals and objects.
If we landed on a planet with a smaller mass than Earth, what would our weight be? Will the weight stay the same without changing? Will it be heavier? Or go away?
I have already said above that gravity is directly proportional to mass. So, on a planet with less mass than Earth, the weight will be reduced, and if it goes to a planet with more mass than Earth, it will be heavier. Even if this weight changes, our mass will not change.
While we are standing on the earth, we are pulling back on the earth with the same gravity that the earth exerts. (Newton’s Action-Reaction explains this.) But the gravitational force we exert back on Earth is negligible.
According to Einstein’s General Theory of Relativity, Gravity is the bending of space and time due to mass. It is said that due to the curvature of space, matter and light follow the curve and become gravity.
Gravity in the universe
The planets orbiting around the sun are held back by the sun’s gravity so that they don’t drift out into space. The moon that once orbited the earth was held back by the earth’s gravity. The moon’s gravity affects the earth again, once again causing the tides to fluctuate.
Due to gravity, the gas clouds are compacted together and become stars. Once a star was formed, the remnants of gas and dust gathered together to form planets again.
Gravity doesn’t just pull objects that have mass. I see light without matter. This was discovered by Einstein. If a powerful flashlight is pointed upwards from the Earth, the color of the flashlight will be red due to the gravity of the Earth. Although we cannot see this with our eyes, we have been able to prove it with scientific experiments.
Due to gravity, black holes become black holes. When stars many times more massive than the Sun die, they go supernova and turn into black holes. The gas left behind after the supernova explosion became very dense due to gravity and turned into a black hole.
The gravity of these black holes is very, very large, so anything that goes into them cannot come back out. Finally, even the light cannot come out again.
Earth’s gravity
Earth’s gravity is very important to us. If there was no gravity, there would be no reason for humans and other life on Earth to exist.
The Sun’s gravity prevents the Earth from escaping from its current path. The path that the Earth takes around the Sun is a very pleasant environment to live in. Because the climate is balanced, it is a good environment for life to thrive.
Earth’s gravity prevents the Earth’s atmosphere from escaping into space. In other words, a world without gravity is unthinkable.
But the gravity of the earth is not consistent in all places. Gravity is greater in places with more mass underground, and in places with less mass underground, gravity is slightly less.
NASA used two satellites to measure Earth’s gravity. The resulting global gravity map is shown below. The blue ones are areas with slightly weaker gravity, and the red ones are areas with stronger gravity.