STAGE 1

Moon enters penumbra

The shadow cone of the Earth has two parts: a dark, inner umbra, surrounding by a lighter penumbra. The penumbra is the pale outer portion of the Earth's shadow. Although the eclipse begins officially at this moment, this is in essence an academic event.

You won't see anything unusual happening to the Moon -- at least not just yet. The Earth's penumbral shadow is so faint that it remains invisible until the Moon is deeply immersed in it. We must wait until the penumbra has reached roughly 70 percent across the Moons disk. For about the next 40 minutes the Full Moon will continue to appear to shine normally, although with each passing minute it is progressing ever deeper into the Earth's outer shadow.

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