1. What is the Theory of Continental Drift?
It was a 17th-century scholar and statesman, Sir Francis Bacon who first noticed that the present-day continents resembled pieces of a giant jigsaw that could be fitted together to form one large landmass. However, it was a German scientist, Alfred Wegener who suggested the theory of continental drift.
According to this theory, all the continents had once been joined together but had split and drifted apart over hundreds of millions of years. This theory has been supported by the fact that ancient fossils and rocks found on different continents are very similar.
Although Wegener made a very important discovery, his ideas were ridiculed during his lifetime.
Recommended Read: What is a Gigafire?
2. Which is the most accurate way to measure continental drift?
We know that the surface of the earth is broken into large pieces or plates that are slowly shifting. The continents rest on these plates, and the speed at which they drift away from each other varies from place to place.
But on average, they move at about the same speed at which your fingernail grows! This may seem to be very slow, but over millions of years, the continents can travel thousands of kilometers!
The most accurate way to measure the speed at which they drift is by using satellites that bounce laser beams from ground stations on each continent. This method is called Satellite Laser Ranging, or SLR.