The Night Sky- Bridget Stewart

PART 1: Locating Stars and Constellations 1. Research and complete the following table for the given constellations: Constellation Brightest Star (common name) Declination of brightest star Right Ascension of brightest star Ursa Major (Big Dipper) Alioth +55°57'35" 12h54m01s Ursa Minor (Little Dipper) Polaris +89°15'50" 02h31m47s Draco Eltanin +51°29'20" 17h56m36s Cassiopeia y-Cas +60°43'00" 00h56m42s Lyra Vega +38°46'58" 18h36m56s Leo Regulus +11°58'01" 10h08m22s Canis Minor Procyon +05°13'39" 07h39m18s Delphinus Rotanev +14°35'42" 20h37m32s Canis Major Sirius ?16°42'47" 06h45m09s Taurus Aldebaran +16°30'35" 04h35m55s Cygnus Deneb +45°16'49" 20h41m25s Bootes Arcturus +19°11'14" 14h15m40s Orion Rigel ?08°12'05" 05h14m32s 2. What are four other names for Polaris? The North Star Alpha Ursae Minoris Kynosoura Guiding Star 3. Use the following seasonal star maps to locate the Big Dipper and the Little Dipper on the maps. Then try to find them on a clear night with the unaided eye. In what season(s) can the constellations be seen? The Dipper constellations can be seen in every season in the Northern Hemisphere. As the seasons pass, their orientation differs though; In the spring and summer the Big Dipper is high in the sky, and in the fall and winter it’s lower to the horizon, the Little Dipper is higher in the sky during winter, while in summer, it’s closer to the horizon. This shift in orientation occurs due to Earth's axial tilt and its orbit around the Sun. As a result, the position of stars in the sky changes with the time of year, offering a new celestial view as the seasons pass. 4. If you were using the sky maps above to locate a specific constellation, how can you tell whether to look for it high in the sky (towards the zenith) or just over the horizon? Be specific. Season: Winter constellations: Generally rise in the east, travel across the sky, and set in the west. They tend to be higher in the sky as the night progresses. Summer constellations: Appear in the eastern sky later in the evening and are often closer to the horizon, especially when the night is young. Time of Night: At midnight, the constellations will be at their highest point in the sky, usually approaching the zenith (the point directly overhead). Early in the evening (just after sunset), constellations will be lower in the sky, close to the horizon. As the night progresses, the constellations rise higher, so by the early hours of the morning, they may be found closer to the zenith. Your Location/Latitude: Near the equator, you’ll see constellations higher in the sky. Near the poles, constellations may appear much lower, and some can even stay near the horizon for extended periods. Constellation Declination: The higher the declination (closer to +90°), the closer the constellation will be to the zenith at your location. High declinations (e.g., near +40° to +90°) will appear higher in the sky in the northern hemisphere. Low declinations (e.g., near 0° or negative values) will appear closer to the horizon, especially in the north or south. So overall, if you were looking for a constellation in the northern hemisphere (like in Ontario) during the winter months at midnight, you could assume that they would be at their highest point of the sky, most likely in the upper half. Then, looking at their declination, you can tell how close they will appear in reference to the zenith. 5. The Big Dipper is often used as a reference point when locating other stars and constellations. How can you use the Big Dipper (highlighted in red on the maps) to locate Polaris in the little dipper. Show this on the diagrams above (you can either print off the diagrams, draw on them and scan/photograph them, or use image editing software to draw on the images, and paste them into your submission). Then, explain in words how to use the above maps to locate Polaris. The star Polaris is located in the Little Dipper (part of the constellation Ursa Minor) and stays nearly fixed in the sky. It has historically been used for navigation as it provides a constant reference point. Unlike other stars, which seem to move across the sky due to Earth's rotation, Polaris marks the direction of the North Celestial Pole. To locate Polaris using the Big Dipper, first find the Big Dipper on your sky map. Identify the two stars at the edge of its bowl, Dubhe and Merak. These are known as the Pointer Stars. Draw an imaginary line between them and extend it outward. This line will point directly to Polaris, which is the bright star at the tip of the Little Dipper's handle. Polaris remains nearly stationary in the sky and marks the direction of true north, making it easy to spot using the Big Dipper as a guide. References