Mississauga Centre RASC

            109th Meeting

                                                                      Members’ Night 

Day:                Friday July 11, 2008

Chair:                Colin Jackson

Speakers:          Leslie Strike

                           William Callahan 

                          Roy Swanson 

General Assemble 2008, a First Timer’s Impression

Leslie Strike attended the recent GA 2008 “Astronomy Night in Canada” staying on campus at York University for 3 ½ days and working as a volunteer. The General Assembly was also meant to prepare for the 2009 International Year of Astronomy (IYA) wherein people will be encouraged to look through a telescope for the first time and experience a “Galileo moment” as Galileo did 400 years ago when he first looked.  

Dennis Grey and Randy Attwood were the co-chairs.  Many papers were presented including topics like the Tunguska impact, 50 years of Canada in space, Ottawa light pollution abatement.  An all-star ball hockey game was held on Saturday with a piper leading the Eastern team.   The Saturday evening members’ night carried on to 12:15 a.m. and 2 telescopes were available for observing at the observatory at York U. 

Sunday was Hamilton Day where Phil Plait spoke about 7 ways that a black hole can kill you.  There was also a lecture about Tagish Lake, and Saul Whitman’s paper about gravity lensing.  In the afternoon, delegates went to the Ontario Science Centre specifically to see the “Facing Mars” exhibit followed by dinner at the Mongolian Grill Restaurant where awards were given out and a lecture about the Mars exhibit was given. 

Day 3 was Toronto Day when the annual meeting of the RASC took place.  Leslie recommended that we have proxy voters for these.  In the afternoon, Terence Dickinson spoke about 50 years in astronomy and Phil Plait gave the Helen Sawyer Hogg lecture on “Bad Astronomy.”  This was followed by a dinner where Bonnie Bird, secretary of the society formally retired.  The GA was a good experience and she recommended to the membership to attend a GA, the next one taking place in Cypress Hills, Sask. next summer.   

Collimating the Orion Telescope

William Callahan showed how to collimate an f/6 Orion Newtonian telescope. Collimation is the art of lining up all the optical elements in the tube.  The higher the

f-ratio, the less critical the collimation.  He described tools such as the Cheshire eyepiece and laser.  First, make sure that the focuser is at a right angle, then make the secondary mirror appear round in the centre. Next, tilt the secondary so that the reflection of the primary mirror is in the centre of the secondary.  Finally, use the laser to allign the primary mirror. 

Observing Meteor Showers

Roy Swanson spoke about meteor showers during the year.  Meteor showers are cometary debris and show best in the morning when the Earth plows into them.  The Quarantids (Dec 28 to Jan 7)  can have bursts of meteors.  The Lyrids in April can be bright and come from periodic Comet Thatcher.  The Eta Aquariids May 4, 5, 6 have a good year in 2008 due to New Moon.  The South delta Aquariids, seen before dawn on July 28, may be from Comet Macholtz and comprise a complicated series of minor showers.  The Perseids from Comet Swift Tuttle will be interfered with this year by the Moon.  On October 7 and 8 we have the Draconids fro Comet Giacobini Zinner. Of note, in 1992 a Draconid hit a car.  The South Orionids (Oct 20 or 21) and North Orionids (Nov 11 and 12) overlap and come form Comet Encke.  Then there are the Leonids on November 17 this year, noted for causing meteor storms every 33 years.  Finally, December 13, 2008 brings the Geminids which will be hampered by the bright Moon. Scientists are still trying to figure out the parent comet but it may be the extinct 3200 Phaethon.  

There is a theory that phosphorus on the Earth may have come from schreibersite, a nickel-iron compound.  Roy then showed a movie of impacts, fragments form the Mars hills, possible life in a Mars rock and meteor showers. 

 Submitted by Chris Malicki, Secretary  Chris Malicki, Secretary                               back to Miss Centre. meeting reports page
Mississauga Centre RASC