AstroNotes 1983 May Vol: 22 issue 04



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The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 22, No. 4 $5.00 a year May 1983

Editor.......Rolf Meier.....4-A Arnold Dr.......820-5784
Addresses....Art Fraser.....11-860 Cahill Dr....737-4110
Circulation...Robin Molson...2029 Garfield Ave...225-3082


Chairman Rolf Meier opened the meeting at 8:30 with 27 people in attendance, about 74% being members. A new lock was installed at IRO on April 1, with a new key fee of $25. Notices of coming events were issued, such as a star night at Quiet Site (April 15 or 16) and the RASC/AAVSO meeting at Quebec City (May 20-23).
Our Deep Sky coordinator Gary Susick presented a talk on telecompressors. Gary says that this device reduces the effective focal length of a telescope. For example, an f/10 telescope can be reduced to f/5, and thereby increase the photographic speed by 4 times. Some telecompressors cause problems such as the window effect, chromatic aberration, and not working well with small diffuse objects such as M 57.
Appearing next was Dave Fedosiewich, talking on comets Temple and Kopff. Comet Temple will reach its brightest in late May, and Comet Kopff reaches its brightest in early July.
Frank Roy presented a slide show of the light conditions at IRO. Sky fog at the observatory is contributed to by nearby city lights and aurora.
Malcom Lambourne was up next to tell the group of the telescope and instrumentation workshop to be held at his house. Information and details can be found in the April 1983 issue of Astronotes.
Rob McCallum talked on the April Lyrids and other showers occurring this month. Rob recalled past showers and how unpredictable meteor observing can be. The Eta Aquarids, which peak on May 5, is unfavourable this year
because the moon is in the last quarter phase and the radiant doesn't rise until later. A possible project for the club is the make a chopper for a meteor camera, in order to be able to determine the speeds of meteor trails.
Finally, Brian Burke spoke about an occultation coming up. Brian also talked about the Variable Star Award and a few variables to observe.
Rolf closed the meeting at 10:30 pm when people were invited for cookies and beverages.


location: 312 Woodroffe Avenue, Ottawa telephone: 729-8112 dates: Tuesday, May 10 6:30 to 10:30
May 26 June 7 June 21

Now is the time to think about telescope making! The annual Stellafane telescope makers' convention is coming up later this summer, so hurry and get it ready for competition! -Ed.



This will be a fantastic month to observe the planets. Since Saturn came to opposition on April 21, it will be rising just before sunset and it will set before sunrise. The tilt of its rings with respect to the earth will be about 14.5°, so observing the major divisions in the rings will be a challenge.

Jupiter comes to opposition on the 27th of this month. This planet is always an intriguing one to observe because there are always changes occurring in the atmosphere. The most prominent feature to have almost faded from view in recent years is the Great Red Spot. Therefore, this is one feature you should try to observe.

Venus, at magnitude -3.7, is very prominent in the western sky at sunset. A challenge to observe is the dichotomy of Venus, which is the time it is 50% sunlit. This will happen between the end of the month and June 20. I have found that Venus is a better object to observe during the day due to the lower contrast. However, when looking for Venus with binoculars or a telescope during the day, always take special precaution not to look at the sun accidentally. Do not forget to write about your observations in Astronotes.


Just a bit of information about the Lyrids.
The maximum was to occur on April 22, with an hourly rate of 15 per single observer, and a duration of 2 days (at 1/4 strength of maximum).
After checking the skies (they looked okay), off we went; Sandy Thuesen, Rolf Meier, and myself (where was our meteor coordinator?). Upon arriving at Quiet Site, not only was the moon casting shadows, but there was a great deal of cloud cover. So, while we waited for the clouds to move out we went on a tour of Quiet Site. We also observed some Canada Geese returning for the summer.
Well, the skies began to clear and undaunted by the moon we set up our lawn chairs. The watch was on. Snuggled in my comforter waiting anxiously for something to happen..."Time!" we cried out. But it was a non-shower meteor. Fighting the temptation to sleep, an hour later I spotted a Lyrid. But after one hour and forty minutes of observation, that was the only Lyrid to be seen. The
saving grace was that at least it wasn't intolerably cold. Let's hope for more promising meteor observing in the future.


Every year there is an award available for members of the Ottawa Centre who observe variable stars. The Variable Star Award will be presented to the person who has made the greatest number of quality estimates on the varying brightness levels of selected variable stars. This year, I have selected six variable stars that must be observed in order to win the award. Only observations of these six
stars will be considered for the Variable Star Award. The six stars are:
star    mag range    period(days)    RA & Dec (1950)
U Cephei    6.8-9.2    2.493    00h 58m +81° 37'
RZ Cassiopeiae    6.4-7.8    1.195    02    44    +69    26
Beta Lyrae    3.4-4.3    12.91    18    48    +33    18
Delta Cephei    3.78-4.63    5.366    22    27    +58    10
Z Ursae Majoris    6.8-9.2    196    11    54    +58    09
R Scuti    4.9-8.2    140    18    45    +5    46

All of these stars can be observed over the coming month, and most of them can also be observed year round. The are all within the range of 7 x 50 binoculars. Observations must be recorded using the local time, UT, and then converting to the Julian date. See page 19 of the Observer's Handbook 1983 for a description of the Julian date. If you would like more information, give me call at 521-8856.



The lead-up to this article can be found in last month's Astronotes.
This month, I would like to write about another type of cloud where organic molecules may be found.

The Black Clouds

These clouds are more dense and opaque than the dark clouds, and could be said to be condensed areas within an extended dark cloud. These clouds are heated by gravitational collapse, where young stars are forming (i.e. the Orion Nebula and the Trapezium). The higher density and pressure gives more complex chemistry than the dark cloud counterpart. The reasons for ionization are not clear, but it is believed to be caused by excitation from member stars. The role of dust grains are uncertain in the synthesis of complex polyatomic molecules. Some chemical components found are dimethyl ether and ethyl alcohol.
Objects like the Orion Nebula are among the most massive in the galaxy, as much as 100,000 solar masses. These objects are readily seen in small instruments.

CHAIRMAN'S REVIEW OF 1982    Rolf Meier

Well, here it is the May issue of Astronotes and I'm finally getting around to reviewing the year past. No excuses, but the many ex-contributors to Astronotes still in the Centre are in no position to complain.
The year's meetings began with your Chairman on his vacation, so the January meeting was chaired by Vice-Chairman Rob McCallum. The January Quadrantids were not observed by the visual team, but Jack Horwood came through once again with his fm-radio observations.
Speaking of meteors, 1982 saw a revival of the Quiet Site. In the spring, a group of observers cleaned up the site. I would like to thank the other members of the Quiet Site Committee, Rob Dick and Rob McCallum, for assisting in the re-opening and summer-long maintenance of the site. A number of meteor session were held at the site, with the assistance of meteor coordinator Dave Lauzon.
Ted Bean dug through the historical archives, and presented a much-appreciated account of the history of the Observer's Group awards. His articles can be found in the January and February issues of Astronotes.
With increasing light pollution, and increasing gasoline costs, Rob Dick had the right answer, and continued to encourage it throughout the year. Observe the sun! So obvious in the sky, and convenient to observe. His accounts of observations can be found in most past issues of Astronotes.
The grazing occultation division finally had a very successful expedition, led by Brian Burke. On April 30, a group of 9 observers travelled to Rockland, Ontario, to the east of Ottawa. Several groups observed multiple events, and certainly made all the years of effort pay off. When will luck be on our side like that again?
The June meeting of the Observer's Group was instrument night, and many interesting devices were on display. Bob Barclay's equatorial platform went on to win a prize at the Stellafane convention later that summer, and was one of the best topics of conversation that night.
1982 was a year of lunar eclipses. The total lunar eclipse of July 6 was well-observed by many people in the Ottawa area. One heard tales of people getting up at 3 am to observe it, and hearing their neighbors up to also observe it. A group went out to Quiet Site to observe the event, and even the kids at the nearby "Y" camp were heard during the eclipse.
While 1982 was not a year of spectacular comets, in the late summer we were treated to Comet Austin, which reached naked-eye visibility for about a week. Meanwhile, the search goes on by a number of members.
Several star nights were held during the summer at our two observing sites, IRO and Quiet Site. The annual picnic was in fact held at QS on September 18, and continued with observations by telescope and of meteors. Also, the 10th annual Deep Sky Weekend was held at IRO on October 16, and a number of observers enjoyed the dark, clear fall skies.
Stellafane was very well represented by the Ottawa Cntre this year, with at least 26 Ottawans counted in attendance.
The Perseid meteor shower was observed to an extent at the Stellafane convention, which coincided with that shower's maximum.
Astronotes, the voice of the Observer's Group, saw its 20th anniversary and 200th issue in December of 1982, with a nice issue.
Congratulations once again to the 1982 award winners. The Observer of the Year for 1982 was Frank Roy, the presentation being made at the Annual Dinner meeting.
During the year it became apparent that attendance at Observer's Group meetings was dropping, and in particular, a decline in the younger membership was noted. Why is this happening? There are several theories. First, the subject matter at meetings is becoming rather specialized, and not enough empahasis on simple observation is being made. I also believe that sane of the coordinators are taking themselves far too seriously. This hobby of ours should be above all fun, and if we get too serious we will discourage people who are getting interested in astronomy for the pleasure of it. Second, the quality and quantity of articles in Astronotes is declining. I think this is an effect, rather than a cause. And third, the regularity of Ottawa Centre main meetings has taken a turn for the worse in the past few years.
In any case, I look to the rest of the current year with optimism. I am with the Observer's Group for the interactions that arise from getting a number of amateur astronomers together. Let's get the observing back into the group. Tell your friends about the club, and get them to come to meetings. And don't forget that a lot of observing can be done right from your own back yard, no matter how bad the skies might seen. And gosh, don't take the whole thing so seriously. It should be fun.