Measuring the orbital period of the Moon using a digital camera

Hughes, Stephen W. (2006) Measuring the orbital period of the Moon using a digital camera. Physics Education, 41(2), pp. 144-150.

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A method of measuring the orbital velocity of the Moon around the Earth using a digital camera is described. Separate images of the Moon and stars taken 24 hours apart were loaded into Microsoft PowerPoint and the centre of the Moon marked on each image. Four stars common to both images were connected together to form a ‘home-made’ constellation. On each image the Moon and constellation were grouped together. The group from one image was pasted onto the other image and translated and rotated so that the two constellations overlay each other. The distance between the Moon centres in pixels was converted into a physical distance on the CCD chip in order to calculate the angular separation on the sky. The angular movement was then used to calculate the orbital period of the Moon. A metre rule was photographed from a known distance in order to calculate the physical size of the CCD pixels. The orbital period of the Moon was measured as 27.1 days, which is within 0.7% of the actual period of 27.3 days.

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ID Code: 20005
Item Type: Journal Article
Refereed: Yes
Keywords: moon, lunar, digital camera, digital image, oribital period, image registration
DOI: 10.1088/0031-9120/41/2/004
ISSN: 0031-9120
Subjects: Australian and New Zealand Standard Research Classification > EDUCATION (130000) > SPECIALIST STUDIES IN EDUCATION (130300) > Educational Technology and Computing (130306)
Australian and New Zealand Standard Research Classification > PHYSICAL SCIENCES (020000) > ASTRONOMICAL AND SPACE SCIENCES (020100) > Astronomical and Space Instrumentation (020102)
Divisions: Past > QUT Faculties & Divisions > Faculty of Science and Technology
Past > Schools > School of Physical & Chemical Sciences
Copyright Owner: Copyright 2006 Institute of Physics
Copyright Statement: Reproduced in accordance with the copyright policy of the publisher.
Deposited On: 24 Apr 2009 00:37
Last Modified: 29 Feb 2012 13:26

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