Astronomy Cafe – Sep 29, 2025

• Intro & Welcome by Reg Dunkley
• RASC Publications for 2026
  • Place pre-orders through Lauri Roche lauri@victoria.rasc.ca by Oct 25th
  • 2026 Observer’s Calendar – $23-25
  • Night Sky Guide 2026 – $16-17
  • Explore the Universe – get a certificate
    • Guide book – $17
    • Workbook – $10
  • Explore the Moon – get a pin
    • Binoculars – $10
    • Small telescope – $10
  • 50 Things To See With a Telescope – $10
• Space Exhibits In Missouri, Ottawa and Sidney – Summer Travels 2025 – Brian Barber
  • Laws Observatory, University of Missouri, Columbia, Missouri
    • History of the observatory, Samuel Laws
    • 16″ SCT – has Cassegrain focal plane as well
    • Schmidt Camera
  • Ottawa
    • Canadian Museum of Nature
    • Huge Moon and Earth globes
    • The Man who Planted Trees – presentation
    • Dinosaur gallery
    • Earth and Space Gallery, including a “Goodwill” Moon Rock
    • Canadian Aviation and Space Museum
    • William Wallace Gibson (1975-1965) – Lansdowne Field powered first flight of all-Canadian built aircraft
    • Canada’s role in space exploration
    • Canadarm
    • International Space Station – life in orbit
    • Health In Space
  • Sidney Museum
    • Health In Space exhibit – May 5 – Nov 30
    • Features David St. Jaques and Robert Thirsk – both doctors as well as Canadian astronauts
  • Time Magazines from 1969 – space missions featured
• Astrophoto – Dave Payne
  • Draco Triplet of Galaxies – not near each other, but spectacular
  • Exposure: ~10 hours over 2 nights in early April 2025
• Hosting Astronomy Cafe next week – Jeff Pivnick
  • New findings about our Sun’s structure will be presented
  • Send any photos of the Sun taken by members to Jeff jeff.pivnick2@gmail.com
• “20 Feet From Stardom” – Astronomers Forgotten in the Shadows – Reg Dunkley
  • Pierre Méchain (1744-1804)
    • Published the Messier List among others
    • Discovered 13 comets
    • Produced hydrographic mapping for coastal France – St. Malo to Dunkirk
    • Precisely measured Earth’s meridian arc (survey completed by 1798), which defined the Metre
    • Pierre Méchain appointed as Director of the Paris Observatory
  • Jesse Ramsden – renowned English instrument maker invented the “Dividing Engine” and a giant theodolite used to establish a survey baseline in England so the median arc could be accurately measured
  • Delambre’s Odyssey
  • The Metric System – history
  • Borda Repeating Circle
• 61 Cygni – Randy Enkin
  • These binary stars (magnitude 5) are moving quite rapidly against the background – proper motion
  • The Aristotelian Universe
  • Copernicus 1543 – Sun in the centre of the Solar System
  • Parallax – shift in apparent relative positions of celestial objects
  • Friedrich Bessel (1838) used his Fraunhofer Heliometer to measure proper motion (parallax) of 61 Cygni
  • Gaia last scientific observation on Jan 10, 2025 – 61 Cygni
  • 61 Cygni’s Parallax is Important
• UVic presentation on Oct 8th – Kevin Bertles
  • “Northern Star” Plaskett documentary – presented by Nick Versteeg

Video transcript of meeting