Cloudy skies and rain greeted students from the London District Catholic School Board, Grade-7 Enrichment Program, for Exploring the Stars at Western University’s Cronyn Observatory, Wednesday, April 6th, 2016, 7:00 p.m. There were 37 visitors in all, including some 21 Grade-7 students and possibly other siblings, one teacher, 14 parents and one small child.
Graduate student Shannon Hicks presented the digital slide presentation “Extra Solar Planets” and fielded questions. Shannon followed this with the activity “Transit Demo,” and invited everybody to the table at the front of the room where she had set up the “Transit Demo” model of an extra-solar planetary system on a turntable with an electrically lighted “sun” in the middle. A photodiode was clamped to a laboratory stand and linked to a laptop computer, which displayed the dipping light curve as model planets of various sizes revolved around and in front of the lighted model sun. The lecture room was darkened with the lights turned off for this very impressive demonstration of how the transit detection method worked for finding extra-solar planets.
RASC London Centre was represented by Everett Clark, Paul Kerans and Bob Duff. Since it was raining, Paul set up the London Centre’s 25.4cm Dobsonian (17mm Nagler eyepiece, 66X) just inside the dome door. Everett and Paul set up the observatory’s 8-inch (20.3cm) Meade Schmidt-Cassegrain telescope (20mm Plossl eyepiece, 100X) immediately behind the 25.4cm Dobsonian, followed by the Orion AstroView 6 (15cm) Newtonian reflector (25mm Plossl eyepiece, 30X), on its equatorial mount, and the 90mm Coronado H-Alpha solar telescope on the Sky-Watcher EQ5 mount, all inside the dome for display.
When everybody arrived upstairs in the dome, Bob gave a talk on the history of the Cronyn Observatory and technical aspects of the big 25.4cm refractor, using his green laser pointer to indicate the 25.4cm objective lens and the finderscopes. Bob also used his green laser pointer to show them the Schmidt camera and Cassegrain reflector telescope piggy-backed on the 25.4cm refractor and briefly explained how they worked. Bob pulled down the big telescope and removed the dust cover to show them the 25.4cm objective lens and Everett installed the 32mm Erfle eyepiece (137X) and pointed the telescope towards the top of the dome to give the visitors the experience of looking through the eyepiece even though the observatory dome could not be opened.
Bob also explained the Standard and Sidereal Time clocks on the east wall and how the reflector and Schmidt-Cassegrain telescopes worked and how the 90mm Coronado H-Alpha solar telescope was used to view prominences and flares on the Sun. The teacher then divided everybody into 2 groups with one group returning downstairs for Paul’s presentation on his meteorites and the other remaining upstairs to view through the amateur telescopes. The 2 groups then changed places so that both had the opportunity to view through the telescopes and examine Paul’s meteorites.
The visitors were delighted with the views through the amateur telescopes, including structure and stonework on the Engineering building in the 25.4cm Dobsonian (17mm Nagler eyepiece, 66X), the TV screen visible in the windows of the Western Student Recreation Centre in the 8-inch (20.3cm) Schmidt-Cassegrain (20mm eyepiece, 100X) and the lights on the communications tower in south London in the Orion AstroView 6 (15cm) Newtonian reflector (25mm Plossl eyepiece, 30X). Paul set out a small collection of meteorites on the lecture room table along with current issues of “SkyNews,” “Sky & Telescope” and “Astronomy” magazines as well as the “Sky & Telescope Pocket Sky Atlas,” by Roger W. Sinnott (c2006), a copy of the RASC’s “The Beginner’s Observing Guide,” by Leo Enright, and 2 books on meteorites. He also set up his microscope for the visitors to examine the meteorites.
Everett shared the “RASC General Assembly and AstroCATS, May 19—23, 2016” poster with some interested members of the group and the poster “A Teachers’ Workshop: Comfortable Astronomy, Thursday, May 19, 2016” with the teacher. The visitors left around 8:50 p.m., after expressing their thanks for a very interesting and enjoyable evening learning about extra-solar planetary transits, telescopes and meteorites, despite the cloudy sky and rain.