# How can we determine during a lunar eclipse whether the earth moves faster or the moon

How can we determine during a lunar eclipse whether the earth moves faster or the moon using minimum instruments?

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Good Question! I'll think about it or ask my teachers. – Cheeku Feb 28 '13 at 23:20
What do you mean by "does the Earth move faster, or the moon"? – Kitchi Mar 1 '13 at 5:27

The diagram above shows the moon just before, during and just after the lunar eclipse. I'm guessing the question is asking whether the velocity of the Moon, $V_m$, is greater or less than the velocity of the Earth, $V_e$.
If so, then you just have to see what direction the Earth's shadow moves across the Moon. If $V_m > V_e$ then the Moon starts at the lower position and moves up past the Earth, so the shadow starts at the top edge of the moon and moves down. If $V_m < V_e$ then the Moon starts at the top position and moves down, so the shadow starts at the bottom edge and moves up.