Mostly cloudy skies greeted 28 visitors (24 children and 4 adults) from the London Waldorf School, Grades 5-6, for Exploring the Stars at Western University’s Cronyn Observatory, Wednesday, March 7th, 2018, 10:00 a.m. They were welcomed by graduate students Viraja Khatu and Jeff Vankerkhove. Viraja presented the digital slide presentation “Our Star: The Sun” and fielded questions. This was followed by the “Building Sundial” activity with Jeff demonstrating how to cut out and assemble a sundial from a pattern on a printed sheets of paper (with the caption “I Tell Only Sunny Hours”) and Viraja supervising as the children cut out and assembled their own sundials.
When everybody arrived upstairs in the dome, RASC London Centre member Bob Duff gave brief a talk on the history of the observatory and technical aspects of the big 25.4cm refractor, demonstrating with the 32mm Erfle eyepiece (137X) and rotating but not opening the dome. Bob explained how the Schmidt camera and Cassegrain reflector telescope piggy-backed on the 25.4cm refractor worked and the difference between a reflector and refractor telescope. Bob also explained the 2 clocks on the east wall and the difference between Standard and Sidereal Time.
Jeff supervised as the visitors lined up to view the Sun through the observatory’s 90mm Coronado H-Alpha Solar Telescope (CEMAX 18mm eyepiece, 44X) on the observation deck, while Bob showed them the Sun through the Meade 20.3cm Schmidt-Cassegrain (26mm Plossl, 77X) with the Kendrick (Baader film) Solar filter. Viraja showed them the wind turbine on the Engineering building through the London Centre’s 25.4cm Dobsonian (17mm Nagler eyepiece, 66X). Clouds obscured the Sun until it briefly appeared towards the end of the observing session and the visitors enjoyed views through both solar filtered telescopes.
Viraja and Jeff then brought the visitors downstairs into the “Black Room” where they presented the “Spectroscopy Demo” with the visitors putting on diffraction grating glasses to view the spectra of 4 gas discharge lamps set out on the table, including: hydrogen, helium, neon and mercury.
After the “Spectroscopy Demo” Viraja brought the children back into the lecture room and had them fill out feedback forms. The visitors were gone by 12:00 p.m. noon, after an interesting and enjoyable morning learning about the Sun and spectroscopy and doing some solar observing, despite the mostly cloudy sky.