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ERIC Number: EJ1080568
Record Type: Journal
Publication Date: 2015-Nov
Pages: 9
Abstractor: As Provided
ISSN: ISSN-0031-9120
In the Red Shadow of the Earth
Hughes, Stephen W.; Hosokawa, Kazuyuki; Carroll, Joshua; Sawell, David; Wilson, Colin
Physics Education, v50 n6 p741-749 Nov 2015
A technique is described for calculating the brightness of the atmosphere of the Earth that shines into the Earth's umbra during a total lunar eclipse making the Moon red. This "Rim of Fire" is due to refracted unscattered light from all the sunrises and sunsets rimming the Earth. In this article, a photograph of the totally eclipsed Moon was compared with the Full Moon and the difference in brightness calculated taking into account the exposure time and ISO setting. The results show that the Full Moon is over 14,000 times brighter than the totally eclipsed Moon. The relative brightness of the eclipsed Moon can be used to estimate that the luminance of the Rim of Fire is over 12 trillion watts. The experiment described in this paper would be suitable as a high school or university exercise.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A