AstroNotes 1981 November Vol: 20 issue 11

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A S T R O N O T E S
ISSN 0048-8682
The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 20, No. 11
$5.00 a year
November, 1981
Editor....... Rolf Meier.......4-A Arnold Dr...... 820-5784
Addresses.... Art Fraser...... 11-860 Cahill D r .. .737-4110
Circulation...Barry Matthews...2237 Iris St...... 225-6600
OBSERVER'S GROUP MEETING - OCTOBER 2
Brian Burke
The meeting
opened
at 8:10
with
40
people
in
attendance, 31 of whom were members. It was announced that
the Deep Sky Weekend would be from October 2-4 at IRO.
Also,
the
grande
star
night
to
celebrate
the
10th
anniversary of the 16-inch telescope would be held on
October 23, 24, 30, or 31.
Also announced was that the
annual dinner meeting would be held on Friday, November 13
at NRC.
Tickets are $12 in advance and $15 at the door.
Finally, members were reminded that membership fees are
due. Fees have increased this year and they are $12.50 for
yo uth and $20.00 for regular members.
First item on the agenda was the nomination of
coordinators for the Observer’s Group. Elections will take
place at the November meeting.
Rolf Meier was up with some slides of past Deep Sky
Weekends.
The solar coordinator, Rob Dick, provided information
about
recent
solar
activity.
He
compared
visual
observations with radio data.
Rob also had slides showing
recent sunspots and he described the life span of these sun
spots.
Jamie Black announced that Steve Dodson from North Bay
has a Celestron-8 for sale with many accessories.
Jamie
then gave a brief description of the chemistry of galaxies.
A series of exposures on the same frame of the July
lunar eclipse was shown by Brian Stokoe.
Brian’s first
attempt at such a photograph was very well done.
Peter MacKinnon then announced the discovery of a new
meteor
shower.
Peter and
two
friends
independently
detected the new shower in September, 1980 while observing
-1-in the southwest U.S.
The radiant appears to be in the
Cygnus-Lyra area.
More information is in the September,
1981 issue of Sky and Telescope.
As occultation coordinator, this writer mentioned that
there would be a grazing occultation in mid-December about
20 km from Ottawa.
Rob Dick announced that anyone interested in building
a photoelectric photometer for the 16-inch should get in
touch with him or me.
Finally, a summary of earlier announcements was made
and the meeting concluded at 9:15
* * *
THE SUMMER STAR NIGHTS
Brian Burke
This past summer there were 3 public star nights.
In
July and August they were held at IRO and in September it
was held in Billings Park.
The July star night had about 30 people in attendance
and at least 6 members brought out their telescopes.
The
young visitors to IRO had their first look at Jupiter and
were excited at seeing the rings of Saturn through the
16-inch.
The star night in August had an overwhelming response
from the public with at least 75 people visiting the
observatory over the course of the evening.
This was
primarily due to the publicity in The Citizen about Steve
Dodson’s telescope.
Steve was kind enough to bring his
22-inch f/7 reflector to IRO for the public and members to
see.
Many very impressive views of deep sky objects were
seen through Steve’s telescope.
The public star night in September was held in
Billings Park.
Approximately 25 people were present to
take a look at objects through the 5 telescopes that had
been set up.
This past summer’s star nights were very successful
and thanks go out to the members who brought along their
telescopes and provided transportation.
* * *
- 2-SOLAR DISC FOR NOVEMBER
Robert Dick
Here is this month’s solar disc, for beta = +3°.
SOLAR ACTIVITY
Robert Dick
Due to bad weather and various commitments, I have
only a few observations of the sun.
These show that the
sun was quite active during October.
Photographs taken on October 11, 12, and 17 show
several large groups present near the equator of the sun.
On October 17, there were 3 large groups, each stretching
about 1/5 the sun's diameter in the east-west direction.
Small groups and isolated spots are appearing at higher
solar latitudes.
These high-latitude spots are to be
expected near solar minimum.
Solar radio observations made by Ken Tapping at 435
MHz show a steady increase in activity throughout the first
weeks of October.
This increase in activity fell after the
flare of October 18 (between 13:09 and 13:40 EDT).
Dave
Pedoslewlch has been monitoring the "skip" of low frequency
transmissions. These are used as a course indicator of the
level of solar activity. He reports that around October 10
end 11 there was "average" skip.
This increased around
October 14 and 15 and it continued to build up to October
23, the date of this writing.
***
-3-
4OBSERVING WITH THE 46-METRE DISH AT ARO
Frank Roy
On October 2-4, 1981, I had the opportunity to use the
largest full-steerable radio telescope in Canada, one of
the largest in the world,
I was a guest of Dr. Paul
Feldman of the H.I.A., and we observed RS CVn stars.
The Algonquin Radio Observatory is the home of one of
Canada’s leading instruments for astronomical research.
The 46-metre dish has been in operation since about 1968,
and it has been proven valuable in the discovery of several
molecules in space.
It has also been used for pioneering
work on long baseline interferometry with the Penticton
radio telescope in British Columbia.
After driving for three hours from Ottawa, 60 miles on
gravel, I arrived at ARO to meet Dr. Feldman. ARO is about
65 miles from Pembroke, the nearest large town, and is in
the heart of Algonquin Park near Lake Traverse.
The staff
house where I stayed is on the lake.
The people there are
friendly, and I would like to thank the cook, Larry, for
the great meals.
Although this is my fifth time there, I was given a
short tour of the observatory by one of the dish drivers.
Friday night was spent mostly learning the workings of the
telescope.
A computer has
complete
control of
the
telescope, so I was basically learning how to use the
computer.
It took Dr. Feldman about three hours to show me
how to operate the instrument.
Five stars are included in the observing program.
They are HR 1099, II Peg, BY Dra, AR Lac, and HD 44179.
All of these stars are visible in a small telescope.
The
stars are double systems with orbital periods from one day
to two weeks.
Thirty of these systems are now known.
HR 1099 is a 6th magnitude star in Taurus.
All of the stars mentioned are usually undetectable at
radio frequencies, but are known to emit powerful bursts of
radio energy on occasion.
Only HR 1099 and II Peg produced observable results.
HR 1099 reached 200 mJy and II Peg produced one small burst
of less than 100 mJy.
HR 1099 has been known to go above
1 Jy, but produced only small bursts during our observing
period.
The ARO observations were part of an effort by several
observatories, including a UV satellite, all observing the
same stars at the same time.
I must admit that it was a very long weekend.
The
computer did about 99% of the work,
and the driver
occasionally repointed the telescope on a new star.
Very
few problems were encountered.
There was a slight problem
-5-with the receiver on Friday, but retuning the receiver up
by several MHz seemed to solve the problem, for it did not
recur.
Now it is clear to me what makes a professional
different from and amateur, and that is patience.
Of
course
computers
and
large
telescopes
help,
but
perseverance and discipline separate the professional from
the amateur. Although it was a long and boring weekend, it
is and experience that I would not pass up.
I would like to extend my deepest appreciation to Dr.
Feldman for inviting me on this project and to have shared
his experience as a professional.
References
The Astronomical Journal; December, 1978, Vol. 83, No. 12;
"The Discovery of Strong Radio Flaring of HR 1099"; p.1471
to 1484.
Sky and Telescope; February, 1979; Vol 57, No. 2; "The
Strange RS Canum Venaticorum Binary Stars"; p. 132 to 137.
* * *
ANNUAL DINNER MEETING - NOV. 13
NRC - 100 Sussex Dr.
$12 advance
$15 door
6 pm
see you thereA S T R O NO TES
c/o
H e r z b e r g I n s t i t u t e of A s t r o p h y s i c s
Nati onal R e s e a r c h C o u n c i l of C a n a d a
100 S u s s e x Drive
Ot t a wa C a n a d a
K 1A 0 R6
First Class Premiere classe
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