The period during a solar eclipseThe passage of the new moon directly between the Sun and the Earth when the Moon's shadow is cast upon the Earth. The Sun appears in the sky either partially or totally covered by the Moon. when the Sun’s photosphere is completely covered by the Moon and the period for a lunar eclipseThe passage of the Moon into the shadow of the Earth, which can only occur at a full moon. when the Moon is in the complete shadow of the Earth.