Total Solar Eclipse on 24 October 1995

Perhaps the earliest scholars of science were the Greeks that lived 2,000 to 3,000 years ago. They observed that, as Sunlight stopped falling on the Moon during an eclipse, it stopped shining. From this, they reasoned that the Moon had no light of its own - shining only by reflecting light from the Sun.

Successive eclipses produced more profound thinking by the Greeks. They noted that as the Earth’s shadow moved over the lunar disk, its edge was not straight but curved. From this they deduced that the Earth must be round – a sphere.

The discovery of the Sun's outer atmosphere, otherwise known as the corona, occurred during the total phase of a solar eclipse – the only time it's on show. Until the advent of the space age, we had no other way of studying this part of the Sun.

Eclipses have helped mankind understand many more phenomena. We've worked out that the degree of darkness of a lunar eclipse, as well as the colour of the Moon during the eclipse, are due to the effect of the gases in the Earth’s atmosphere: gases that light has to pass through before it hits the Moon's surface. This knowledge gives us important clues to atmospheric conditions.

By measuring the positions of stars near the Sun at the only time they can be seen – during a solar eclipse - we've also been able to prove relativity, Einstein's revolutionary theory about the universe.

Finally, because we can calculate the dates of past eclipses as well as future ones, we have a reliable and accurate way of establishing the exact dates of historical events that records say coincided with these rare occurrences.