Open up your laptops, go to MrHyatt.rocks, and do today’s bellwork Scale Scale Description 4 Through independent work beyond what was taught in class, you could: investigate the location of seasonal constellations in the local sky. predict location of constellations at future times. determine the celestial equator, latitude and position of the Pole Star for a given position on the Earth. determine the distances of stars in a given constellation to each other and to Earth. 3 You will be able to: describe and apply the coordinate system used to locate objects in the sky. distinguish the various methods of measuring astronomical distances and apply each in appropriate situations. 2 determine the meaning of symbols, key terms, and other astronomy specific words and phrases as they are used in context to relevant topics label diagrams with degree measurements describe how or why different units of measurement are needed for distances in space 1 You will be able to list the different units of measurement needed to measure distances in space

Use an ENTIRE page in your journal. Make it BIG. Due was today Use an ENTIRE page in your journal. Make it BIG! Due was today! I hope you got it done!

Astrolabe The astrolabe was invented in Greece either by Hipparchus of Nicaea, a 2nd century B.C. astronomer, and the “father of trigonometry.” Or Apollonius of Perga, a 3rd century B.C. mathematician and geometer. Hipparchus of Nicaea Appolonious of Perga

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. It basically measures the height of an object in the sky

You are going to create your own Astrolabe You will need: Template Cardstock Paperclip String Half a Straw 2 1” pieces of tape Hole Punch Glue stick Scissors Trash Can Brain At my desk

Copy this on the top of a new page in your journal Object Angle of Altitude #1 (inside) degrees #2 (inside) #3 (outside) #4 (outside)

Sun Measurement Date Time Angle of Altitude #1 Monday 9/18 degrees #2 Monday 9/25 #3 Monday 10/2 #4 Monday 10/9

Moon Measurement Date Time Angle of Altitude #1 Monday 9/18 degrees #2 Monday 9/25 #3 Monday 10/2 #4 Monday 10/9

To become familiar with how an astrolabe works, practice measuring the altitude (angular height) of trees or buildings. To make a proper measurement, look at the top of the object through the straw. Have someone read the altitude in degrees from the side of the astrolabe. The point where the string crosses the scale is the proper measurement. Practice using your astrolabe by measuring and recording another tree or building of a different height. Now that you have an understanding of how an astrolabe works, you can use it to measure the motion of the Sun.  

Because it is harmful to look directly at the Sun, a new method for measuring the Sun's altitude must be used. Hold the astrolabe so that the straw points in the direction of the Sun. Do not look through the straw. Aim the straw so that you see the shadow of the straw on your hand. Move the straw slightly until a small circle of light forms on your hand. The straw is now pointing directly at the Sun. Ask someone to read the Sun's altitude (in degrees) where the string crosses the scale. Take note of the time of day the reading was made.

One day a week, at the same time each day, measure the altitude of the Sun with your astrolabe. Make four consecutive measurements and record them in the chart provided. Be sure to include the date. As the weeks progress, look at your measurements of the Sun's altitude. Can you detect a change? Is the altitude increasing or decreasing? Is there a pattern of change? How can you explain these changes?

Object Angle of Altitude #1 (inside) degrees #2 (inside) #3 (outside) #4 (outside) Sun Measurement Date Time Angle of Altitude #1 Monday 9/18 degrees #2 Monday 9/25 #3 Monday 10/2 #4 Monday 10/9 Moon Measurement Date Time Angle of Altitude #1 Monday 9/18 degrees #2 Monday 9/25 #3 Monday 10/2 #4 Monday 10/9