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Why Does the Moon Appear Larger at Some Times?


Areas of Science
Time Required
Very Long (1+ months)
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Some claim the Moon appears larger when near the horizon. Make a series of observations of the Moon, measuring the Moon's angular diameter each time. You should also note the Moon's altitude above the horizon, and the Moon's phase. You should do background research on the lunar orbit to determine the necessary time period. Do you find predictable variations in the Moon's diameter? Can you relate this to the Moon's changing distance from Earth? From your data, try to determine when apogee and perigee occurred during your observations. Compare your calculated answer with published dates (Pierce, 2005). For another method of measuring the distance to the Moon, see How Far Away Is the Moon?


Pierce, J., 2004. "Ideas for Astronomy Science Fair Projects," Astronomy Program, Minnesota State University, Mankato [accessed December 01, 2011] https://mavdisk.mnsu.edu/wp5884kt/scifair.html.
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MLA Style

Science Buddies Staff. "Why Does the Moon Appear Larger at Some Times?" Science Buddies, 28 July 2017, https://www.sciencebuddies.org/science-fair-projects/project-ideas/Astro_p030/astronomy/why-does-the-moon-appear-larger-at-some-times. Accessed 3 Oct. 2022.

APA Style

Science Buddies Staff. (2017, July 28). Why Does the Moon Appear Larger at Some Times? Retrieved from https://www.sciencebuddies.org/science-fair-projects/project-ideas/Astro_p030/astronomy/why-does-the-moon-appear-larger-at-some-times

Last edit date: 2017-07-28
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