Mississauga Astronomical Society

51st Meeting

Members’ Night

Day:                Friday, November 18, 2005

Chair:         Phil Mozel

Speakers:         Randy Attwood

                         Chris Malicki

                         John Gavrow

                         Ken Davey

Mars Night at Mountsberg Conservation Area

Phil Mozel spoke about the clouded out but otherwise successful star night held at the Mountsberg conservation Area.

The Sky for the Coming Night

Randy Attwood, using the Starry Night program, demonstrated the shallow angle of the ecliptic in the autumn and how this makes the crescent Moon appear very low in the sky. He showed a comparison of the low altitude of Venus in September and its high altitude in March.  He used the program to show the orbits of the inner planets and their transits including the Mercury transit on November 8, 2006, and Venus transits.  He also showed the drift of the Moon’s orbit and its occultations of the Pleides star cluster to take place in the next three years.

Annular Solar Eclipse in Avila Spain

Chris Malicki and his wife Liz traveled to Spain to observe the annular solar eclipse of October 3 under a perfect sky.  Chris described the eclipse, Spain, his experienced with other eclipse observers and newspaper articles.  One unexpected highlight was a beautiful ceiling painting of Pegasus showing the warrior Bellerophon being thrown off as two flies were biting the winged horse.  (see 43^rd  meeting on June 24, 2005 for Phil’s talk about this myth.)

Galileo

John Gavrow spoke about the life and accomplishments of Galileo.  It is remarkable how little people know of this most famous astronomer.  Although he did not invent the telescope, he made many important telescopic discoveries.  In 1610 he published his book “The Starry Messenger” to explain his observations.  With his crude telescope, Galileo made a remarkably accurate drawing of the Moon showing maria, craters and earthshine. The appearance of mountains, valleys and flat plains indicated that the Moon has features similar to those on the Earth.  Galileo’s telescope had a very narrow field of view, but despite this he was able to draw the belt and sword region of Orion, differentiating stars that could and couldn’t be seen with the naked eye.  Galileo was unable to make out the Orion nebula due to his poor lenses.  Looking at the Milky Way he was able to state that it is composed of an unfathomable number of stars. 

One of the most famous of Galileo’s observations was that of the moons of Jupiter which bear his name.  Galileo’s sketched their motion proving that Jupiter contains its own mini “solar system” accompanying it in space.  With four bodies not orbiting the Sun, and by observing Venus’ phases, Galileo found strong support for the heliocentric theory of Copernicus.  To protect himself against the inquisition, Galileo wrote a fictional dialogue with arguments for and against the theory.  Despite this, he was found guilty and put under house arrest. 

John showed pictures from Florence images of Galileo’s telescopes, his middle finger, tomb etc. 

Birr Castle and Observatory in Ireland

Ken Davey and his family traveled to Ireland in July and visited Birr Castle and the observatory built by William Parsons the 3^rd Earl of Rosse  The 72 inch telescope, known as the Leviathan of Parsonstown was located at 53 degrees north and 187 feet above sea level.  William Parsons was a scientist and member of Parliament and philanthropist donating 12,000 pounds during the potato famine.  The telescope was built between 1841 and 1845.  The inch thick wooden tube is 54 feet long with a diameter of 8 feet tapering to 7 feet at the ends.  The 72 inch mirror of speculum metal copper and tin had to be re-polished every 1 to 2 years.  The telescope was raised with chains using a hydraulics system.  It was the largest telescope mirror in the world for 70 years until the 100 inch of Mount Wilson.  With only 30 to 40 clear nights per year, the Earl was still able to discover the Whirlpool “nebula” had spiral structure.  A special plaque commemorates this discovery. The telescope has been refurbished and is currently used at the Lord Rosse Star Party.      

Submitted by Chris Malicki, Secretary  Chris Malicki, Secretary                               back to M.A.S. meeting reports page
Mississauga Astronomical Society