Question

when total solar eclipse occurs why is partial eclipse also seen from the Earth

Answer 1

A partial lunar eclipse occurs when the Earth moves between the Sun and Moon but the three celestial bodies do not form a straight line in space. When that happens, a small part of the Moon's surface is covered by the darkest, central part of the Earth's shadow, called the umbra.

Answer 2

Solar eclipse. ... During a partial solar eclipse (right), the Moon blocks only part of the Sun's disk (October 23, 2014). A solar eclipse occurs when a portion of the Earth is engulfed in a shadow cast by the Moon which fully or partially blocks sunlight. This occurs when the Sun, Moon and Earth are aligned.