Clear skies greeted 26 visitors (13 children and 13 adults) from the 1st Kintore / Thamesford Cub Scouts for Exploring the Stars at Western University’s Cronyn Observatory, Wednesday, March 11th, 2015, 6:30 p.m. Graduate student Dilini Subasinghe began with the activity “Telescope Kits”, with the Cubs assembling small telescopes from reusable kits. Dilini then made the digital slide presentation “Cub Scout Astronomy Badge” and fielded questions.
RASC London Centre was represented by Bob Duff and Mark Tovey, later joined by Tricia Colvin. Mark set up the 25.4cm Dobsonian (17mm Nagler eyepiece, 66X) on the east side of the roof patio outside the dome. At Mark’s suggestion Bob and Mark also set up the Observatory’s 8-inch (20.3cm) Meade 2080/LX3 Schmidt-Cassegrain on the roof patio’s west side. Mark then opened and rotated the dome towards the south and Bob assisted as Mark directed the big 25.4cm refractor (32mm Erfle eyepiece, 137X) towards the flashing white lights on the communications tower in south London. It was an opportunity for Mark to become familiar with setting up and operating the big 25.4cm refractor. When everybody arrived upstairs, Bob gave a brief talk on the history of the Cronyn Observatory and some technical aspects of the big 25.4 cm refractor. As the sky darkened the dome was rotated towards the west and Mark centred Venus in the big 25.4cm refractor’s field of view (32mm Erfle eyepiece, 137X).
Bob suggested everybody divide into 2 groups with one group going outside to view Jupiter through the 25.4cm Dobsonian, supervised by Tricia, and the 8-inch (20.3cm) Meade 2080/LX3 Schmidt-Cassegrain, supervised by Mark; and the other group remaining inside to view through the big 25.4cm refractor. Dilini supervised from the top of the observing ladder as the visitors climbed the steps to view Venus through the big 25.4cm refractor. Jupiter was a splendid sight in the 25.4cm Dobsonian, supervised by Tricia, with all 4 Galilean moons visible in the field of view of the 17mm Nagler eyepiece (66X). Mark began by showing visitors Jupiter and its 4 Galilean moons through the 8-inch (20.3cm) Meade Schmidt-Cassegrain using the 18mm Tele Vue Radian eyepiece (111X), which was soon replaced with the 12.5mm Ortho eyepiece (160X) at Bob’s suggestion. The higher magnification of 160X made Jupiter a spectacular sight in the Schmidt-Cassegrain, although only 3 of the Galilean moons were visible in the narrower field of view. Bob opened up “Starry Night Pro” on the dome computer, finding Jupiter; with Dilini later finding Mars and showing some of the Cubs its moons, Phobos and Deimos, and a few features on Mars, including Valles Marineris and some craters.
When everybody in both groups had viewed Venus through the big 25.4cm refractor and Jupiter through the 25.4cm Dobsonian and 20.3cm Schmidt-Cassegrain, the telescopes were redirected towards other sky objects. Mark showed visitors the Pleiades (M45) star cluster in the 20.3cm Schmidt-Cassegrain (26mm Plossl, 77X) and Bob located the Orion Nebula in the 25.4cm Dobsonian (17mm Nagler eyepiece, 66X). Tricia took over supervision of the 25.4cm Dobsonian as Bob went inside to redirect the big 25.4cm refractor towards the double-star Castor, which was nicely split in the 32mm Erfle eyepiece (137X). Bob explained the nature of the double-star Castor to several interested visitors. Towards the end of the evening Bob redirected the 25.4cm refractor again, this time towards Jupiter, which made a splendid sight in the 32mm Erfle eyepiece (137X) field of view, with its cloud belts and all 4 Galilean moons visible. It was an enjoyable sight for the few remaining visitors to view Jupiter through the big 25.4cm refractor.
Everybody in both groups had a chance to view through all 3 telescopes and most of the visitors were gone by 8:30 p.m. after expressing their thanks for what was an excellent evening of astronomy. A few people remained behind until around 8:50 p.m., by which time the telescopes were being put away and the Observatory closed down.