LAB: Constellations by Season and Coordinates in the sky Part A. Coordinates in the Sky 1. Consider the imaginary constellation "Pezaglis" which has the 4 stars shown the table to the right a. Plot these points on the Mercator Map b. Connect the stars with lines, in order given including a line from delta back to alpha Label the stars with the correct Greek symbol Stars of Pezaglis Declination Name Ascension Alpha 40° 23h Beta 40° 1h Gamma 70° 1h Delta 70° 23 h d. Plot these same points on the Polar Map, again connect the stars. e. Now, use a "Celestial Sphere" to see what shape it would be in the sky
2. Discussion: You will probably find that the "shape" of the constellation is different on the two maps. Briefly, which map do you think more closely represents how it would appear in the sky (equivalently on a celestial sphere) to you eye? Explain your reasoning
3. Consider two more stars: epsilon at (70° 4h) and zeta at (70°, 16h). a. Plot them on the Mercator Map. Label with correct Greek symbols. b. Using a ruler, connect them with a straight line (i.e. the shortest path). c. How many degrees apart are they (on the Mercator Map]? {Hint: 1 hour is equivalent to 15°} d. Explain how you arrived at your answer to part c
4. Plot these same stars on the Polar Map. a. Using a ruler. connect them with a straight line. Label with correct Greek symbols b. How many degrees apart are they ( on the Polar Map )? c. Explain how you arrived at your answer to part b.
5. Discussion: Are the distances you measured on the two maps the same? Which map probably represents what you would see in the sky? Again, use a "Celestial Sphere" to resolve any interpretation issue of the correct "line" to draw between the two stars. [Are the lines you drew on the two maps representing the same thing?]
