Mississauga Centre RASC

112th Meeting

                                                      Speaker’s Night  

Day:                Friday September 26, 2008

Speaker:          Roy Bishop

Impressions of Some Observations Sky, Land and Wildlife of the Southern Hemisphere

Roy Bishop is a professional physicist and amateur astronomer, Past  President of the RASC in the 1980’s, former editor of the Observer’s Handbook and a major contributor incorporating personal computing to the handbook.  

Roy Bishop has been south of the equator three times.  Three years ago he was on a bus tour from Uruguay to Chile going through Mendoza, then Santiago, La Serena, Antofagasta, Paranal and to Salta.  The headquarters of the European Southern Observatory (ESO) are in Santiago Chile.  Further north near La Serena  is located Cerro Pachon with Gemini South, an 8.1 meter telescope on an altazimuth mount covered with silver, not aluminum.  20 km away, on a ridge at Cerro Tololo is a telescope similar to the one on Kitt Peak.  Of note, the centre of the Milky Way passes through the zenith here.  Further north is Las Campanas, run by the Carnegie Institute,  with 6 ½ meter Magellan telescopes.  The U of T Southern Observatory used to be located here.   Just to the south is the ESO site of the New Technology Telescope (NTT). With the NTT, the entire building rotates with the telescope on an altazimuth mount and with adaptive optics.

Further north at Paranal is the Very Large Telescope (VLT) of the ESO built at a cost of $500 million.  . The four 8.2 meter telescopes have mirrors made of zerodur with good thermal expansion. They are named Antu (Sun), Kueyen (Moon), Melipal (Southern Cross), Yepun (Venus) in the indigenous Mapuche language.  They can operate separately or as an interferometer (VLBI) together with the 1 to 2 meter smaller telescopes as the equivalent of a 120 meter telescope.  Paranal is 12 km from the Pacific Ocean. The Humboldt Current produces an inversion layer keeping the sky clear and dry. As a result, it has 340 clear night per year with seeing of 0.3 to 0.7 arcsec.  An image of the black hole region in the centre of the galaxy was shown with its excellent resolution. This possible under such good conditions.

Further up at 16,000 feet is the location of the planned Atacama Large Mirror Array (ALMA) for 2012.  It will work in the microwave range in the extremely dry air. 

Roy’s second trip south of the equator was in March 2008 when he went on a cruise from Ushuaia to the Falkland islands, South Georgia, Tristan da Cunha and Cape Town.  One of his tasks was to show the southern sky to other passengers.  They visited a number of places that Captain Cook had seen on his voyage, specifically, South Georgia.  It is a rocky rugged island with spectacular mountains and glaciers, many penguins, a whaling museum,  and Shakleton’s grave.  Then it was off to Tristan da Cunha.  At Cape town, the current image of the town with Table Mountain was compared to a drawing from Herschel’s time. 

The third trip was to Australia with its fabulous clear southern skies including the Milky Way, Southern Cross and Coalsack nebula.  

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