Clear skies with a few high wispy clouds greeted 24 visitors (10 students and 14 adults, including the teacher and parents) from the London District Catholic School Board Grade 7 Enrichment Class, for Exploring the Stars at Western University’s Cronyn Observatory, Tuesday, March 20th, 2018, 6:30 p.m. Graduate student Dan Hatfield presented the digital slide presentation “The Life and Times of Stars” and fielded questions. This was followed by demonstrations of the “Transit Demo” and Spectroscopy Demo” in the downstairs “Black Room.”
Downstairs in the “Black Room” Dan gave demonstrations of the “Transit Demo” model—showing how the transit detection method worked for finding extra-solar planets, as well as 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.
RASC London Centre was represented by Everett Clark and Bob Duff. Everett made ready the big 25.4cm refractor (Meade 28mm Super Wide Angle eyepiece, 157X) in the dome and set up the London Centre’s 25.4cm Dobsonian on the observation deck. Bob installed the 17mm Nagler eyepiece (66X) in the 25.4cm Dobsonian and directed it towards the wind turbine on the Engineering building. When everybody arrived upstairs in the dome, Bob gave a talk on some of the history of the Cronyn Observatory and technical aspects of the big 25.4cm refractor. He explained the Schmidt camera and Cassegrain reflector piggybacked on the 25.4cm refractor—opening and closing the shutter on the Schmidt camera for demonstration. He also called their attention to the 2 clocks on the east wall of the observatory and explained the difference between Standard and Sidereal Time.
Everett then directed the 25.4cm refractor towards the 3-day-past-new crescent Moon in the bright early evening western sky, which made a fine sight for the visitors through the Meade 28mm SWA eyepiece (157X). Dan and Everett tried using the hour angle and declination coordinates from the planetarium software on the computer to locate the double star Castor, and Everett soon centred it in the 25.4cm refractor’s field of view after Bob pointed out Castor and Pollux in the twilight sky. Bob showed the visitors the Moon, and later the star Sirius, through the 25.4cm Dobsonian (17mm Nagler eyepiece, 66X) set up on the observation deck.
The visitors enjoyed the views though the 2 telescopes and asked many good questions. Everybody was gone by around 8:30 p.m. after a very interesting evening of astronomy under clear skies.