Introduction

Gary Case presided over our meeting, as Chris had a prior commitment. Gary noted that this seems to be our one day of summer, so perhaps our speaker has to compete not only with a change from the usual date, but also outdoor activities.

There will be several star parties throughout the summer. Our Star-B-Que is advertised in SkyNews for July 28-30 (http://www.sji.ca/rasc/starbq2006.html). Dave Lane also reminded us not to forget about Nova East in case anyone travels to the Maritimes (http://halifax.rasc.ca/ne/).

Observations

A handful have seen Comet Schwassmann-Wachmann. The comet is now visible at 4 am.
David Caruk: saw the faint part of the comet.
IAD: Randy spoke on the event briefly. The event was mostly cloudy, so the views were of Jupiter, Saturn, the Moon, and the Sun (through the PST).
The Caruk brothers took part in similar observations for the IAD at the Toronto Science Centre.

Suggestion

There should be a telescope workshop at our Star-B-Que, so the general public can bring their scopes, get advice, and learn how to use them.

Sky Next Month

Robert gave us a tour of the sky next month, starting with a visit to Sky Hound. We were given some idea of the deep sky objects visible. The site also contains a section on comet Schwassmann-Wachmann (73P) now in/near Pegasus. Robert then turned to the planets and discussed Jupiter and Saturn. Spaceweather.com indicates there may be some aurora over the next two nights.

Robert gave us a report on International Astronomy Day. There were about 40 or so visitors and our site now contains a number of pictures of the event. Unfortunately, clouds covered most of the event. The new location at the Fluvarium, combined with the bad weather may have accounted for the drop in numbers.

David Lane

David Lane is visiting the province from the Halifax Centre. The talk is on "AROSS: Chasing Bacon with the Abbey Ridge Observatory Supernova Search!" Dave promised to explain the bacon reference later on. AROSS stands for Abbey Ridge Observatory Supernova Search.

Dave then explained roughly what a supernova is, and the differences between a type Ia supernova, and a type II supernova. The type Ia is important as a "standard candle", used in determining galactic distance scales. When discovering supernova, it is important to remember that the last visible one in our galaxy occurred about 400 years ago. There is one supernova every 50-100 years in certain types of galaxies. Your chances of discovery vastly increase if you scan as many other galaxies as you can.

Dave gave an overview of how he and Paul Gray discovered Canada's first supernova, 1995F. We can contrast this with a fully automated observatory, using a scientific-grade CCD. We were given a tour of ARO, specifically the location, the dome, and the equipment used. Dave developed a lot of the electronics, hardware, and software himself, this being his field of expertise. More can be found at http://www.davelane.ca/aro/ .

Some hilights of the immense work gone into this endeavour would include the AR Auto Pilot scripting language to control dome operations. A barcode scanner arrangement is also used, along with 96 barcodes arranged around the inside periphery of the dome, to control dome rotation.

Dave plans to survey about 2700 galaxies over 2033 fields, all located at 55 degrees or greater in declination. These targets were developed from the PGC catalog, using galaxies of 15.5 magnitude or brighter. These targets are grouped into 38 boxes to enable efficient slewing amongst these boxes. Typically, it takes 45 seconds for the CCD to acquire an image, and given typical Halifax weather he expects half of the galaxies can be surveyed in a given month. Paul Gray gets the nightly observations and blinks them with Maxim DL. Given that Dave isn't living in Arizona, there can be expected to be a number of near misses. Dave gave a few examples, including some frustrating "pre-discoveries". Happily, there have been two discoveries: SN2005B and SN2005ea.

The North York Astronomical Association has had a challenge for Canadian Astronomers to discover another supernova. The winner would get 500 loonies, 1 toque, and 1 pound of back bacon. Dave and Paul did indeed bring home the bacon with their 2005 discoveries!

Some statistics:

2004: 37 nights, 8008 galaxies
2005: 64 nights, 17570 galaxies

There followed a question and answer session. One of the more important questions concerned search automation. Dave explained that most of the supernova were at the detection limit. Using software to detect them automatically (by blinking) would mean losing a lot in the noise, or too many false positives that would need to be looked into.

Coffee

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David Bourgeois

This document was generated using AFT v5.095 and Vim on: Mon May 22 22:41:51 NDT 2006