AstroNotes 1980 August Vol: 19 issue 08



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The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 19, No. 8 $2.00 a year August, 1980
Editor........Rolf Meier.......77 Meadowlands Dr.W...224-1200
Addresses Jacqui Tapping...61 Oval Dr., Aylmer...684-1186
Circulation.. .Barry Matthews. ..2237 Iris St........ .225-6600
The General Assembly of the RASC was held this year
in Halifax at Saint Mary's University from June 28 to 30.
This was the first joint meeting with the CAS and RASC.
Friday was the first day of RASC activities. There
was a National Council meeting in the afternoon, which was
very long, being interrupted by supper and finally the
RASC reception in the evening. This was followed by various
slide shows, notably Toronto Centre's eclipse expedition
to Africa.
Saturday was a paper session day. On the whole, the
CAS papers were better in content, delivery, and interest,
while the RASC papers were often trivial and uninteresting.
A highlight of Saturday evening was the annual RASC
banquet, featuring lobsters which fought back. The
speaker was Dr. John Percy, who praised smaller (less
than 24-inch) telescopes and the work which he and others
have conducted with them. The Chant medal was presented
to David Levy, and the service award went to our own
Stan Mott.
The song contest was held later with our own Renee
Meyer and Mary Geekie winning the prize for our Centre.
Unfortunately, their singing was better than the prize.
There were more papers on Sunday. Our own Rob
McCallum and Mike Roney combined to produce a paper on
the determination of the maximum of a cepheid variable
light curve.
The annual meeting of the RASC was held, with
Dr. Ian Halliday taking over as president. This was
followed by a short council meeting.
On Sunday afternoon, the RASC went to the Halifax
Yacht Club for a "picnic". This was followed by a
ISSN 0048-86822-hour cruise on the Bluenose II, which took place in
Strong winds.
The display awards presentation ended the GA. There
were 24 entries in 7 categories, with 7 displays being
entered by Ottawa in 6 categories. Of the 7 awards, 5
went to the Ottawa displays. The winners were as follows:
Centre Display - Winnipeg
Individual Display - Damien Lemay (Quebec) - Sunspots
Optical Observing - Rob McCallum and Mike Roney
Radio Observing - Rob Dick
Design Project - Doug George
Amospheric Phenomena - Rob McCallum
Open Category - Rolf Meier
Next year's GA will be held in Victoria, BC.
Mary Geekie and Renee Meyer
Chairman Robt Dick opened the meeting at 8:15 pm
with 42 people in attendance, 10 of whom were non-members.
The group is reminded that Ted Bean is still looking for
someone to take over hospitality as he wishes to step
Brian Burke informed the group that last month's
public star night was clouded out at first, but it cleared
up at midnight. Observers will have another star night
on July 18. By mid-month, the planets will be setting just
after sunset, Brian also informed the group that the
Beginner's Package will be available by early fall.
Bob McCallum proceeded to show the group the Ottawa
Centre members' displays recently entered at the Halifax
General Assembly. The Ottawa Centre won the prizes in 6
of 8 categories as follows:
optical observing - Rob McCallum and Mike Roney
radio observing - Rob Dick
atmospheric observing - Rob McCallum
design project — Doug George
open category - Rolf Meier
song contest - Renee Meyer and Mary GeekieA more detailed account of the GA will be presented at the
next meeting. Congratulations to all who entered. Rob
also suggested the possibility of holding a Centre picnic
complete with baseball game and star night in late summer.
The new RASC president, lan Halliday, presented the
Service Award to Stan Mott. This prestigious award was
given to Stan for his outstanding service and contributions
to the Ottawa Centre and to the RASC as a whole. Stan,
who was nominated by the centre, has served 32 years on
the Council and has been a supporter and invaluable
librarian for the Ottawa Centre since 1956.
Another honourable award, the Chant Medal, was
presented to David Levy at the GA in recognition of his
extensive variable star observations (2000 a month) and
for his contributions to the education of children in the
field of Astronomy.
Congratulations to Stan and Dave!
Rob McCallum has kindly donated a gift certificate
for historical books to the library from his GA prize.
There was a reminder that the maximum for the Perseid
Meteor Shower occurs August 12 (so start observing).
Doug Welch informed the group that a number of
observers are going to observe the variable star CY
Aquarii in many different ways, in order to put together
a centre project display for next year's GA. This star
has a regular pulse of 88 minutes, but sometimes it
experiences abrupt period changes. These bold observers
intend to compile visual observations, photographic
photometry, a Cepheid instability strip, a movie, and la
piece de resistance - the size of the earth's orbit.
Ted Bean warned amateur mirror grinders of the
problems of chipping and creating hollows in mirror
blanks due to over-enthusiastic grinding. There will be
no more telescope-making workshops until the fall.
A Celestron-8, including A eyepieces, crosshair,
wedge, drive corrector, and no tripot is for sale, for
$1500. Call Ted for details at 224-7318.
Dave Fedosiewich showed slides and propaganda for
the annual Stellafane convention to be held August 9 this
year. Dave pointed out various unique telescopes, mounts,
Rolf Meier explained the fundamentals of a camera and
guided system. Rolf also discussed pictures that were
taken with long focal length cameras, telephoto lenses,
and the Aero Ektar at IRO. The brown background effectof the slides may now be eliminated due to its being
re-cemented. Next month Rolf will attempt to mount the
camera on the telescope.
Bill Donaldson explained his method of calculating
sunspot length and area. Bill projects the sun on a
piece of paper and compares the size of the projected
image with the size of the real sun. This ratio is then
applied to the image of the sunspots to caluclate their
The meeting was adjourned at 9:36 pm.
At the July Observer's Group meeting I mentioned the
possibility of having a picnic. Well, there seems to be
sufficient interest, so we've decided to go ahead.
The picnic will be held on Saturday, September 6. If
this seems a little late in the year, let me explain the
reasoning. Plans are to have the picnic evolve into a
star night come dusk. By September it will be dark by
9 pm, so those who wish to bring the family need not be
out too late.
It is still a little early, so we haven't as yet
found a suitable location. It won't be in the city - we'd
like dark skies for the star night. Gatineau Park,
Lac Philippe in particular is a possibility, but we first
would have to obtain permission to remain after dark. We
should know definitely by the time you read this. If you
can't make it to the August or September meetings, or if
you simply want more information, please phone one of the
members of the "organizing committee":
Rob McCallum 729-9977 (home) 563-2868 (office)
Rob Dick 722-5809 231-3885
At present we plan to have the event officially start
with a ball game at 4 pm (no skill, just a sense of humour
required), but as we will likely be near a beach, you can
plan on making a day of it, if you wish. And if you are
staying for the star night, and you have a telescope, be
sure to bring it. Lastly, dress warmly - it'll likely be
cool once the sun goes down.
In case of rain, give either Rob or Rob a call on the
day of the picnic. We'll decide around noon whether or
not to call it off.CY AQUARII: THE PROJECT Doug Welch
There is surely nothing more impressive in the field
of variable star observing than watching a star change in
brightness before your eyes. Among the stars which vary
rapidly enough to fit this description, CY Aquarii is
king. CY is among a breed of variable called dwarf
cepheids. These stars generally have periods between 1
and 5 hours and vary in brightness by 0.3 to 1.0 magnitude.
Thus it is possible to observe several full cycles of
light variation in the same night! What will be described
here is a project to observe this star as completely as is
possible for an amateur.
The project will have several aspects. These are:
a) visual
b) photographic
c) cinematographic
Let us consider these in turn.
Visual observations will consist mainly of magnitude
estimates made every 5 to 10 minutes - 5 preferably.
These will determine the shape of the light curve and,
more importantly, the time of maximum of the magnitude
variations. This will alow the determination of period
change when compared with previous observations.
If you have never observed variable stars before, this
is a good star to get a lot of experience with little
investment in time. It is suggested that you submit all
observations, but indicate at what point in time you
think you became "comfortable" with the observations.
The success of the photographic aspect of this venture
will rest mainly on the construction of a photographic
photometer. This instrument will measure the brightness
of stars on exposures taken with the 16-inch. This
would be an excellent addition to the instrumentation
at IRQ and its users are certainly not restricted to
observing CY alone. I believe that the construction of
one of these instruments is now under way.
Photographic photometry will allow the determination
of the shape of the light curve and comparison with
visual observations. The maxiu of the light curve will
also be determined accurately with this method. Furthermore, if V and B photometric filters are used alternately,
it will be possible to determine the extent of colour
change during a cycle.
Finally, there is the cinematographic aspect of the
project. This is mainly for aesthetic purposes and willdemonstrate nicely how spectacular the light variation
of this star is. The basic idea is to take the exposures
from a photographic observing run and make super-8 films
using them. Negotiations are currently under way to
convince Jon Buchanan to produce and direct the film.
An interesting offshoot of the observations will
be the ability to determine the size of the earth's orbit!
This is possible because of the proximity of CY to the
ecliptic. As you all know, light takes about 499 seconds
to travel from the sun to the earth. So if it were
possible to observe CY at opposition and at conjunction,
there would be a shift of about 1000 seconds in the time
of maximum which is not due to the period of the star
changing. Due to observing constraints (you can't
observe a 1th magnitude star near the sun) the effect
that we can observe will be more on the order of 600
seconds. Still, this is a sizeable fraction of the
period of CY and the effect should stand out clearly in
visual observations.
Lest you think this is all talk, at the time of
this writing 2 sets of observations have already been
made. On July 4, immediately following the Observer's
Group meeting, Rob McCallum, Doug George and I observed
between 1:30 and 2:30 am and obtained consistent results.
On the following Saturday, Doug George, Brian Burke,
Mike Roney, Frank Roy, and Rob McCallum were able to
make another run. I am particularly glad to see Doug
and Brian observing; this is their first attempt at
variable star observing.
One point I should stress is the necessity of no
bias when observing either by yourself or with others.
If you expect the star to continue brightening or
fading, a maximum can be "forced" where it doesn't
actually exist. As a result, some scatter in the light
curve is expected. When observing with others, all observations must be written down and there should be no
comparison of observations until the observing run is
over. Time Must be CHU or WWV. All observations
should be given to Rob McCallum.
While I have purposely avoided mentioning too many
specifics in this article, Rob McCallum will have a
handout with observing instructions and a chart at the
August meeting. I should mention the brightness and some
references. CY is located at 22h 35.2m, 1° 16' N (1950).
The range is approximately 10.4 to 11.2, depending on an
individual's colour sensitivity.This is a golden opportunity for a group of amateur
astronomers to show the professionals that amateurs are
capable of professional quality results.
1) Astronotes; August, 1977; page 7
2) JAAVSO; No. 1, 1978; page 19
3) Observer's Handbook 1979; page 123 (comparison stars)
4) Burnham's Celestial Handbook, Vol. 1; page 184.
(good finder chart)
The members of the Ottawa Centre are pleased that
the National Society has awarded the Service Award of
the Society to Stanley A. Mott in recognition of his
contribution to the Centre, particularly in his role as
librarian. Although he was not able to be present at the
General Assembly in Halifax to receive the award, the
society's president, Dr. Ian Halliday, presented him
with the bronze medal at the Observer's Group meeting
of July 4, 1980. Congratulations, Stan!
Following are the description of the Service Award
as extracted from the constitution of the RASC and the
citation prepared by the Centre in nominating him for the
"The Service Award is a major award given to a member
in recognition of outstanding service, rendered over an
extended period of time, where such service has had a
major impact on the work of the Society and/or a Centre
of the Society. The award is a small bronze medal which
is given only by resolution of the National Council upon
recommendation of the awards committee of the Council.
The award shall be presented at the annual meeting of the
"Stanley A. Mott, nominated by the Ottawa Centre. He
is a life member of the Society, and became a member in
1938. He was Treasurer of the Ottawa Centre from 1947 to
1957, and since then has continuously held the positionof Centre Librarian. He has thus served on the Council of
the Ottawa Centre for 32 years. As librarian, he has
built up an outstanding library of some 300 books, often
by contributing his own money to the Library Fund. He is
present at all lecture meetings and opens the library at
every meeting of the Observer's Group. In addition to his
work with the library, he has made substantial donations
to the original Observatory Fund and also to the Observatory Relocation Fund. For many years he was a very active
meteor observer, and he was a member of the group which
flew to North Bay by RCAF Dakota to observe the Giacobinid
meteor shower of 1946. He was a regular member of the
Ottawa Centre Meteor Observing Team during the International
Geophysical Year. In addition, Stan has observed the
solar eclipses of 1954, 1963, 1970, 1972, and 1979. One
should also note that Stan and his flash camera have recorded many of the highlights of General Assemblies and
Ottawa Centre events, and one of his photographs was
used in Dr. McKinley's book, "Metoer Science and Engineering". The impact of Stan's contribution to the
success of the Ottawa Centre can hardly be overestimated.
From the June, 1970 issues "Several of the steps for
which we have been pressing, as outlined in last month's
Editorial, seem on the way to fulfilment so far as the
National Newsletter is concerned. The cost of printing is
to be investigated and a recommendation to increase the
size to 'not more that 8' pages has been made to National
Council. A list of names was put before the meeting and
a vote taken on each. The name securing the most votes
was 'Newsletter', with 'Convergence" second and 'Albedo'
### ######
Articles for the September issue of Astronotes are
due by August 22.
# ## # # # ###STOP THE PRESS:
WANTED: 6 Members to work on the Dinner
Committee. Call Jacqui Tapping
684-1186 before August 10, 1980a s t r o n ot e s