IMG_3842
In my pre-eclipse talk, I was describing how eclipses work, and needed some prop's - a snail shell will do!
Look at the shadow of the snail shell - both a lighter and darker shadow is visible. The torch represents the Sun, and the snail-shell is the Moon.
The Earth must pass through the darker shadow (the Umbra) for a total eclipse to happen. If the Moon is slightly further away, as it frequently is due to its elliptical (oval) orbit, the Moon would be unable to completely obscure the Sun, and the Earth would only pass through the lighter shadow (the penumbra) causing an Annular Eclipse.
Similarly, during a Lunar Eclipse, the Moon passes through both the lighter and darker shadow cast by the Earth.
IMG_3842
In my pre-eclipse talk, I was describing how eclipses work, and needed some prop's - a snail shell will do!
Look at the shadow of the snail shell - both a lighter and darker shadow is visible. The torch represents the Sun, and the snail-shell is the Moon.
The Earth must pass through the darker shadow (the Umbra) for a total eclipse to happen. If the Moon is slightly further away, as it frequently is due to its elliptical (oval) orbit, the Moon would be unable to completely obscure the Sun, and the Earth would only pass through the lighter shadow (the penumbra) causing an Annular Eclipse.
Similarly, during a Lunar Eclipse, the Moon passes through both the lighter and darker shadow cast by the Earth.