Is the Gravity lower in different parts of the Earth? What is Gravity and how it works?
Gravity is what holds our world together.
There are certain regions in the world where the impact of gravity differs from the rest of the world. Before knowing any more about such places, let’s have a look at what gravity actually is. The scientific definition says that Gravity is the force by which a planet or any other body attracts an object towards its center. This force is a necessity to keep all the planets in their respective orbits around the sun. It is the reason behind the observation that things fall down when they are either thrown or dropped.
The effect of gravity grows with the mass of the body. As Earth is a massive body, the combined gravitational pull of our planet is quite significant. This force of attraction is what gives birth to the concept of ‘Weight’. That’s why the weight of an object varies when you move out of the gravitational field of the Earth.
Gravity is vital for our survival as the gravitational force of sun keeps the Earth in its orbit. This ensures that we are at a comfortable distance from the giant ball of fire. The temperature remains suitable and we enjoy the warmth of the sunshine. The trees and mountains will go out of their positions and this can lead to huge earthquakes which can be catastrophic. Having said all that, certain variations are observed by NASA in the strength of the gravitational field in different parts of the world. The reason described for this is that the regions with more mass underneath the surface of the Earth attract things much more powerfully than the less mass parts of the globe.
Scientists have worked for years to figure that out. Ultimately, it came down to the advancement of science and technology. A pair of satellites, known as Gravity Recovery and Climate Experiment (GRACE), were used to collect a lot of data. The area under observation included different parts of Canada and special attention was paid to the Hudson Bay and surroundings. German Aerospace Center joined forces with NASA to carry out this research in 2002.
The satellites were launched in a way that they have a 220 kilometers distance between them once they were 500 kilometers away from the surface of the Earth. They were equipped with microwave ranging system to give them extremely high precision while measuring distance differences. This feature was used to examine the varying effects of gravity.
Prior to this discovery, two theories were proposed by the researchers. The latter of them focused on the Hudson Bay. It said that the missing gravity in this part of the world is due to the melting of the Laurentide Ice Sheet. It was heavy and was exerting quite a lot of pressure on the Earth. As it melted away, it caused an indentation there. Due to this, Earth was displaced and the mass of the Hudson Bay reduced. As mass is directly proportional to gravity, the gravitational pull was condensed.
The first major theory that came forward in this regard was related to the convection occurring in the Earth’s mantle. It is actually a layer of molten rocks located underneath the surface of the Earth. The name given to it is ‘Magma’. Due to extremely hot temperature, it creates convection currents. These movements displace the continental plates of our planet. This changes the mass of those areas and their gravity changes correspondingly. Which one of these theories is correct? This million dollar question was answered by this experiment and it was found that both of these were true to a certain degree.
There are many other places in the world where gravity is very low and it seems as if there is no effect of gravitational pull at all. Some of these places are:
· Inverted Waterfall in Chile
It is located in the jungles of Chile and guess what, it can flow from bottom to top. The direction of this waterfall is changed by the wind.
· Mount Aragatas
It seems as if gravity has no role to play here as rivers flow against it. The most amazing thing for tourists is that your cars can move up without using their engines.
Computer Scientist by qualification who loves to read, write, eat, and travel