Celestial Shadows – Eclipses of the Sun and Moon

Speaker: Howard Simkover

Every couple of years, somewhere on the Earth, the Moon’s shadow touches down and sweeps at supersonic speed across oceans and continents. People situated in the path of this celestial shadow experience the unforgettable sight of a total eclipse of the sun. While some ancient civilizations had a good understanding of solar eclipses, it was not until the early 18th Century that the date, time and trajectory of an eclipse could be calculated with reasonable precision.

On occasion, we may also see the full Moon enter the shadow of the Earth, giving us a lunar eclipse. At these times, the eclipsed Moon glows with an orange or reddish colour. Lunar eclipses provided an early proof that the Earth was round, and also enabled the determination of the Moon’s distance.

This presentation is about the various types of eclipses what they are, when they happen, the underlying geometry that causes them, why they are perceived to be rare events, and the spectacular beauty that they offer to us.

Howard Simkover has a lifelong interest in astronomy, owns and uses several telescopes, and was a ProducerLecturer with the Montreal Planetarium. He has lectured about astronomy at the Canada Museum of Science & Technology, and to groups in Ottawa and elsewhere both in person and via Zoom technology. In this highly visual presentation, he will offer some perspectives on solar and lunar eclipses, and will share some of his personal experiences of these phenomena.

This meeting will be via Zoom video conference.

Join us at https://tinyurl.com/opcug-meeting. The Zoom link will be live at 7:15 pm. The meeting will begin at 7:30 pm.

The above link includes the meeting ID and password. However, if you are prompted for the information, use:
Meeting ID: 924 9556 0898
Password: opcug

Instructions for using Zoom are provided here: https://opcug.ca/wp-content/uploads/Zoom-instructionsv3.pdf

Until further notice, Q&A sessions are no longer held after regular monthly meetings. Hence, monthly meetings now end 1 hour earlier at 9 pm. Everyone is welcome to join us on all other Wednesdays for weekly Q&A sessions.


Nov 08 2023


7:30 pm - 9:00 pm

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