by 10:33 0 comments

The astrolabe was invented in Greece either by Hipparchus, a 2nd century B.C. astronomer, or Apollonius of Perga, a 3rd century B.C. mathematician. For many centuries, it was used by both astronomers and navigators, and especially by the 15th century explorers who used it to determine latitude, longitude, and time of day.

Measuring the Altitude of Trees and Buildings
1 To make a proper measurement, look at the top of the object through the straw.
2 Read the altitude in degrees from the side of the astrolabe. The point where the string crosses the scale is the proper measurement.

Now you the mathematical formula to calculate the height based on angle and distance.

Keep the Asrtolabe on a table. Look at a celestial object, like a bright star or planet through the straw as you locate the object, the protractor will rise to a certain angle. You can read this angle with the help of thread with suspended metal bob. Record this angle. Repeat this several times and confirm your reading.
To know angle that the object is making to the Pole star, find out North direction using magnetic compass. Place the Astrolabe with its horizontal pointer facing north and 0 on the circular protractor aligned to the pointer. Now slowly rotate the wooden baton to your left (or right) till you can sight the object again. This will tell you angle of the object with respect to the North.


Post a Comment

Add your own Experience...