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Astronomy 102, Fall 2003

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Astro 102 Labs

A Tour of the Sky

The Celestial Sphere

The Telescope

Angular Distances

How the Labs Work

Labs To Do

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Fist and Finger Rules

The concept of angular size is explained on the first page of this article at Sky & Telescope's web page.

In the lab, you will be using "crossbows" to make more precise angular measurements. However, you can make rough measurements just sighting along your arm, stretched at full length, and comparing the separation between objects to the size of your hand held in various different positions. The pictures below demonstrate several measures you can make in this manner:

[Fist] [Little Finger Tip]
[Open Hand] [Three Fingers]

Last modified: 2003-January-07, by Robert A. Knop Jr.

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