Measuring the Night Sky

You can use your hand to measure parts of the sky. Number the digits, thumb and fingers, on your hand from one to five. Start with your thumb as number one, and end with your pinkie as number five.

To measure 25 degrees extend the first and fifth digit, and spread them as far as you can. When you extend your arm, the distance between your first and fifth digit is 25 degrees in the night sky. Use Ursa Major (Big Dipper) constellation to test your measuring skills. The distance between the stars indicated below should be 25 degrees.



To measure 15 degrees extend your second and fifth digit, and spread them as far as you can. Extend your arm to the objects you plan to measure. The distance between your second and fifth digit should be 15 degrees in the night sky. It should take about six 15 degree had measurements to measure the distance between the horizon and the zenith. The distance between the stars indicated below should also be 15 degrees.



To measure 10 degrees make a fist and extend your arm with your palm down. From the base of your 2nd digit to the base of your 5th digit is 10 degrees. The distance between the stars indicated below should be 10 degrees.



To measure 5 degrees extend digits 2,3, and 4. Hold them closely together. The distance between the stars indicated below should be 5 degrees.


To measure 1/2 of a degree extend digit 5. To test this try measuring a full moon. The moon is about 1/2 of a degree wide.

Special thanks to Astrophotographer Naoyuki Kurita, publisher of Stellar Scenes for use of his photographs. Stop by his web site for other great astrophotographs. His work is copyrighted, so please do not copy them without his permission.