To identify constellations and stars with the help of a planisphere *

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1 OpenStax-CNX module: m To identify constellations and stars with the help of a planisphere * Siyavula Uploaders This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License NATURAL SCIENCES 2 The earth and beyond 3 The Stars 4 5 EDUCATOR SECTION 6 7 Memorandum Assignment 1: Follow the directions in the module and let each learner make a planisphere. Instead of a paper clip, a thumb tick and Prestik can also be used. Ensure that the hours are marked as follows on the upper disk of the planisphere. How to make the planisphere outside. 1. Hold the map to the light. It has to show downwards, so you can see the constellations. 2. Find the place on the upper disk where "midnight" is indicated and ensure it points south. (Ensure that the eastern and western horizons are in the correct "places".) 3. Turn the upper disk so that the precise hour lines up with the correct date on the lower disk. 4. The stars that are visible through the plastic should now also be visible in the sky above you. Assignment 2: This activity can be completed in class. To keep it simple, bear the following in mind: 1) provide a date, e.g. 26 May; * Version 1.1: Mar 12, :23 am

2 OpenStax-CNX module: m ) and a time, e.g. 21:00 or 22:00. Keep the times full hours and not minutes before or after the hour. It is important that the learners know that stars are ALWAYS in the heavens, even during the day. But we cannot see them then. Decide in advance which date is to be given to the learners, so that enough constellations and bright stars will appear in the window of the planisphere. 8 LEANER SECTION 9 Content 10 ACTIVITY: To identify constellations and stars with the help of a planisphere [LO 1.2] As all stars are not visible throughout the year. A planisphere, a model for assisting a viewer in nding constellations in night sky and recognising individual stars is used. ASSIGNMENT 1 MAKE YOUR OWN PLANISPHERE 1. Draw or make a photostat copy of the following form on sti cardboard and mark o the 24 hours of the day along the outside edge.

3 OpenStax-CNX module: m Figure 1 2. Cut out the section that is indicated, using a sharp cutter. Cover the opening with sti plastic as indicated in the sketch.

4 OpenStax-CNX module: m Figure 2 3. Photostat the following star chart of the constellations in the Southern Hemisphere: cut it out along the outer edge and glue it to the cardboard. IMPORTANT TO KNOW: The names of the brightest stars are shown in bold print. 4. Make a small hole in each of the circles and use a paper clip to keep them together securely on top of one another, as in the sketch.

5 OpenStax-CNX module: m Figure 3

6 OpenStax-CNX module: m Figure 4 NOW USE THE PLANISPHERE AS FOLLOWS: Rotate the top disc to align the relevant time with the date of the relevant day on the bottom disc. The constellations that are visible through the plastic window will be those that appear in the night sky on the particular date.

7 OpenStax-CNX module: m Figure 5 ASSIGNMENT 2 Your educator will provide a date and a particular time. Consult your planisphere and copy down the names of all the constellations and bright stars that are visible at the particular time. Make a clear distinction between constellations and bright stars.

8 OpenStax-CNX module: m Figure 6

9 OpenStax-CNX module: m Educator's AssessmentCRITERIA Constellations indicated correctly. 2. Bright stars indicated correctly. 3. Neatness Table Assessment Learning Outcome 1:The learner will be able to act condently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientic, technological and environmental contexts. Assessment Standard 1.2:We know this when the learnerconducts investigations and collects data.