Two Profound Facts about Lunar Eclipses

(This is a follow-up on my earlier post, "Lunar Eclipse 2010".)

1. Once the Moon enters the central portion of Earth's shadow, it will be bathed in red-orange light. Why is that? Besides being very unusual and pretty, the cause of this is actually profound: that orange-red color is the light cast by the sum of all sunrises and sunsets happening on the Earth at that moment.

Don't follow what I'm saying? Here's a video I threw together:



2. Because the Moon is entering the Earth's shadow, it's a rare chance to directly observe the spherical shape of the Earth. While you've certainly never doubted the truth of the fact that the Earth is round and not flat, have you ever really sought proof for it? Unless you plan on a voyage to interplanetary space anytime in the near future, lunar eclipses are the most visually-arresting demonstration of the fact.

Incidentally, the ancient Greeks were the first to realize Earth's shape (and systematically compile the other evidence for it as well). Sort of turns the old "In 1492, everyone told Columbus he'd fall off the face of the Earth!" claim on its head! If true, those must have been some uneducated people, even for their own time.

For an explanation and schedule of the eclipse, see my earlier post, "Lunar Eclipse 2010".