Moon's shadow moves over Earth
An annular eclipse of the Sun swept across the Iberian peninsular today, 3 October 2005. The eclipse, the first in the region for over 90 years, was witnessed by ESA staff at the European Space Astronomy Centre, Madrid, Spain.
The condition for an annular eclipse to occur, apart from Earth, Moon and Sun lining up, is that the apparent diameter of the Moon is smaller than the apparent diameter of the Sun.
At the point of totality when the Moon lines up exactly with the Sun, the Moon will not fully cover the solar disk, leaving a ring of light (annulus) still visible around the Moon.
