As India observes a spectacular solar eclipse, and TV channels can’t seem to talk beyond religion and astrology, lets remember the biggest scientific breakthrough linked to a solar eclipse.

Proving Einstein’s General theory of relativity a 100 years ago.

A thread(1/n)

In 1915, Einstein postulated that the space-time fabric gets warped around heavy objects. Due to this even light, which otherwise moves in a straight line, should bend while passing a heavy object.

The closest heavy object for us is the Sun. There was one problem though. (2/n)

Light from other stars grazes past the Sun to reach Earth all the time. However, Sun is so bright that observing this light, especially from stars in Sun’s periphery, is close to impossible.

Observing this would require something of Sun’s mass but much lower brightness. (3/n)

Solar eclipse to the rescue!

1919 saw the longest solar eclipse of 20th century lasting full 6 minutes. This was enough time for scientists to plot the apparent locations of stars in Sun’s periphery and compare them to the actuals without Sun in the picture. (4/n)

The breakthrough photograph from this 1919 experiment below.

The white blob is the star and the red mark on its right shows where it should have been without Sun’s interference! (5/n)

This conclusively proved the limitations of Newtonian physics in describing the universe, marking the end of an era. Einstein’s theory was proven right.

All thanks to a solar eclipse 100 years ago. (6/6)