Why can't the Moon always pass through the center of the umbra?
A) The Moon's rotation is slightly faster than its revolution around Earth.
B) The Moon's orbit is inclined by 5 degrees to the plane of Earth's orbit.
C) The Moon's synodic cycle changes a few minutes per cycle.
D) The Moon's orbit changes with the seasons.
E) The Moon is not in its full moon lunar phase.

Question

Quizplus · Accepted Answer

The Moon's orbit around Earth is inclined by about 5 degrees relative to the ecliptic plane (Earth's orbital plane around the Sun). This inclination means that the Moon's position relative to Earth and the Sun varies, so it does not always pass directly through the center of Earth's shadow (the umbra) during a lunar eclipse. Instead, it might pass above or below the umbra, or only partially through it, depending on its position in its orbit.

Why Can't the Moon Always Pass Through the Center of the Umbra