On this day in 1919 Arthur Eddington was on the island of Príncipe off the West Coast of Africa. There he took a series of photographs (including the one shown here) of the solar eclipse that occurred on that day. Using the photographs, Eddington determined by how much the stars near the Sun's limb appeared to shift from their positions when the Sun is in a different part of the sky. The magnitude of the shift, which was due to the bending of starlight by the Sun's gravitational field, was consistent with the predictions of Albert Einstein's general theory of relativity.
