Thursday, October 23, 2014

Viewing a Partial Solar Eclipse Indirectly (and SAFELY)


Safety is extremely important when viewing a partial solar eclipse.
NEVER look directly at a partially eclipsed sun without proper eye protection.
We have solar filters for our field scope, binos and our 10" Dobsonian.
But there are other ways to view an eclipse indirectly, without needing special equipment.

CAST SHADOWS
During the partial phases of a solar eclipse, you can see the sun's crescent shape in the dappled sunlight beneath leafy trees. The shape of the crescents corresponds to the shape of the solar disk at that particular moment. There was a little bit of a breeze during the partial eclipse today, so hundreds of little crescents were dancing in the shadows below the trees.

You can also create crescents by holding your fingers overlapped in a criss-cross to create a tic-tac-toe patterned shadow. It takes a little "focusing", moving nearer or further from a light colored surface, to get the crescents to appear.

A loose weave straw hat will also cast hundreds of tiny crescents in its shadow. Again, you can play with angle and distance from a white surface to get maximum effect.

PINHOLE PROJECTION
Use a pin to punch a small hole in a 3X5" notecard. Hold the card so the light coming through the pinhole is projected onto a flat white surface. You will see the crescent shape of the sun in the projected light.

No comments:

Post a Comment