AstroNotes 1969 December Vol: 8 issue 10

EDITORIAL . A THIRD SUCCESS WITH THE PLEIADES? . VARIABLE STAR SECTION . CENTRE MEETINGS . THE DOMINION RADIO ASTROPHYS1CAL OBSERVATORY . TELESCOPE FUND .

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ASTRONOTES       Vol. 8. No. 10     December. 1969

Editor: Tom Tothill 22 Delong Drive, Ottawa 9
Addresses: Howard Harris 620 Keenen Ave, Ottawa 13
Circulation: Ted Bean 399 McLeod St, Ottawa 4

EDITORIAL

Towards the end of November we found it necessary to
write to sunny Alberta to ask if there was still a sky up
there, so constantly have the clouds filled our skies. A
few diehards have stayed up all night weekends to get a few
glimpses through chinks in the cloud but most of us have
simply admitted defeat in front of the Boob Tube.
Fortunately that engine of mental retardation has had
something to show us, for once, in the flight of Apollo 12
to the Ocean of Storms. Even though the TV colour camera
packed up after a good beginning, Pete Conrad's infectious
curiosity and humour came through delightfully and the
linkup with Yankee Clipper was beautifully captured by
Richard Gordon's camera. The Clipper is nearing Earth as
this is written so there is still one crucial re-entry to
be completed before we can be sure of the astronauts' safe
return with their precious cargo of fully-documented moon
rocks photographed in situ before collection, and the pieces
taken off Surveyor III. We are beginning to forget the
ever-present reality of danger that these men face with
such apparent light-heartedness, because everything has gone
so smoothly in the last few flights, but just suppose it
had been the computer that packed up instead of the very
much less complex TV camera ....

The first men on the moon are due in Ottawa any day
now and it is to be hoped that they will get the warm and
cordial reception they so richly deserve, with not too much
stuffy formality and tiresome speeches. Obviously they
must have had a bellyful of that sort of thing during their
world-girdling tour and are probably longing most of all to
get home and be themselves again.

To Neil Armstrong, Buzz Aldrin, and Michael Collins
we express our profound admiration and thanks for the
greatest step mankind has ever taken.
* * * * * * * * * * *

A THIRD SUCCESS WITH THE PLEIADES?

Tom Tothill

The moon will occult the Pleiades for the third time
this year on Dec 21. We got the other two. Ask me for list.

VARIABLE STAR SECTION

Rick Lavery

In future, would all observers please bring their
observations from the past month to the Observers Group
meeting so that an accurate total can be presented at the
meetings.

The Award has been ordered and should be ready for
display at the December meeting. The award will be presented
annually by the Variable Star Coordinator to the
individual with the highest total of observations (excluding
the coordinator himself) for the year. Should the
Variable Star section ever become inactive the Award
should be given to the person who is deemed by the Chairman
to have contributed greatly in stellar astronomy (i.e.
nova, comets, deep-sky, or double stars).
* * * * * * * * * * *

CENTRE MEETINGS

After the film night on Oct 23 when we saw "TO THE
EDGE OF THE UNIVERSE", a film about the first long-baseline
interferometry experiment between Penticton and
Algonquin Park, introduced by Dr. Tom Legge who was a
principal member of the team, and "THE EAGLE HAS LANDED",
the film of Apollo 11, introduced by Tom Tothill, the
moon rocks arrived in Ottawa for study and were on display
weekends at Booth Street.

Dr. Peter Millman's talk "Our Moon" on Nov 20 was a
masterpiece of clear presentation illustrated by slides.
Although, as he said, he has been giving talks on the moon
since 1931, this one proved to be up to the minute in a
rapidly expanding knowledge of the moon. He had microscope
photos of the Ottawa samples and very good photos
of some of the specimens at Houston where he had been
only a week or two earlier. These Apollo 11 samples had
been classified (A) fine grain, dark grey rocks (B) coarse
grain, lighter grey with brownish tinge (C) breccia with
inclusions of vari-coloured small pieces in a generally
deep brown matrix, and (D) dust and small particles. All
the rocks are characterized by pits on the rounded upper
surfaces, frequently lined with a black glaze, and sometimes
showing small black glass spheres on their surface.
The under sides of the rocks are more likely to have sharp
corners and no pits.

The talk also covered recent theoretical approaches
to age determinations for various areas of the moon, the
relationship of tektites to Tycho,etc. A memorable evening.

THE DOMINION RADIO ASTROPHYS1CAL OBSERVATORY

Geoffrey D. Cameron

The Dominion Radio Astrophysical Observatory is devoted
to the study of astronomical problems by means of radio
techniques. It is operated by the Dominion Observatory, and
was officially opened on June 20, 1960. The observatory is
located in British Columbia's scenic Okanagan Valley, a
short distance south of Penticton. Since the DRAO is administered
by the federal department of Energy, Mines, and Resources,
most computer work is channeled through the Computer
Science Division of this department.

The observatory has at this time five main pieces of
equipment:

  1. The 26 metre reflector. This consists of a large paraboloidal mirror some 84 ft (26 m) in diameter which collects radio waves and reflects them to an antenna situated at the focus. The telescope accepts signals at a wavelength of about 21 cm, that is, a frequency of 1420 mc/sec. This choice of operating frequency was made because atomic hydrogen gas, which is thought to make up 3% of all matter In the galaxy, emits radio waves at this frequency. There will be variations due to the Doppler effect, and thus the structure and internal motions of the galaxy can be determined.
  2. The 22 mc/s radio telescope. This consists of a large antenna array built in the form of a "T", the crossbar of which is approximately 0.8 mile long. The entire array occupies 16 acres. It accepts signals with a wavelength of 44 ft (13.5 m) corresponding to a frequency of of 22 mc/s. The direction along the north-south line is changed by switching various segments of the array in and out of the circuit, while the earth's rotational motion provides the east-west motion. This telescope is used primarily in the study of our own galaxy, the Milky Way, as well as some 1000 nearby galaxies.
  3. The 10 mc/s radio telescope. This is very similar to the 22 mc/s scope, except that it accepts signals at the lower frequency of 10 mc/s.
  4. The 10 mc/s interferometer. This apparatus monitors continually the emissions from certain well-known strong stable sources of radio energy. The purpose is to assess the effect of interferences from sunspots and other extraneous sources, in order to be better able to weed out noise signals received in the other equipment.
  5. The solar telescope. This radio telescope is used to monitor radio emissions from the sun at a wavelength of 11 cm. A network of such telescopes around the world assists in the prediction of solar flares and other disturbances, so that warnings may be issued if necessary.

The bane of the optical astronomer is cloudy skies and turbulence in the atmosphere. The radio astronomer has his problems in the form of extraneous noise, or interference, both natural and man-made. The Penticton site was chosen because the Rocky Mountains which surround it on all sides form a natural shield against a great  many unwanted signals. Unfortunately a few spurious emissions still get through into the equipment. Under certain conditions, fortunately rare, bursts of noise are recorded which, it has been discovered, emanate from taxi-cabs in Vancouver. For the past four years or so the DRAO has been engaged in a complete survey of the entire sky visible from Penticton during the course of the year. A box of some

2000 punched IBM cards is received in the Computer Science
Division on the average of once a week. These cards are
generated automatically by the recording equipment connected
to the telescopes. The cards are processed immediately
on the departmental computer facilities, and preliminary
calculations are mailed back to DRAO. Finally, the cards
are placed in a data bank and eventually will be used to
produce machine-drawn contour maps of the heavens, the contours
representing lines of equal signal strength. The
total volume of cards on hand is nearly half a million.
During the past summer a small area in the Milky Way was
used as a test for the proposed system. In only a few
minutes a contour map was produced automatically, using a
CalComp plotter, and the features on this map were almost
identical to those on a previously hand-drawn contour map
which required hours to create.

The electronic computer was also an essential tool in
a recent investigation of radio signals originating from
the planet Jupiter. This project was carried out jointly
by DRAO and the NRC observatory in Algonquin Park. The
two observatories were synchronized by atomic clocks and
this gave the effect of one huge telescope several thousand
miles long. Once again the CalComp plotter was used to
display the information pictorially, to assist in spotting
the radio signals and. weeding out the background noise. Up
to the present, no astronomer has laid his reputation on
the line and said that there are little green men on Jupiter
sending us messages. It seems certain that the emissions
are some natural type of signal, similar to that produced on
earth by thunderstorms.
* * * * * * * * * * *
(We were delighted to get this interesting article from
Geoff Cameron, who works in the Computer Sciences Division
at EMR, and hope it will start a trend of professional
articles to add depth to Astronotes. -Ed.)
* * * * * * * * * * *

TELESCOPE FUND

Rick Lavery

The first month of the Fund saw magnificent contributions
from the enthusiastic, stalwart adults of the Observers
Group. Considering that they had also been called on
to make donations to other causes such as the United Appeal,
Gyro day, etc, about the same time, their response has been
wonderful.

What about the junior members? Only two have given so
far, and one of them had just come to the end of an expensive
project. What's wrong with the rest of you? You will be
the ones who will expect to get the most use out of the
Sixteen Inch. According to the latest consumer reports you
have over 60% of the country's buying power. The Ottawa
Centre has brought us to the present point of construction
by donating the mirror, but it's up to us to turn that into
a usable instrument by building the mount and drive.
We had hopes that the Centre members at large, including
professional members, would see this as a project worth
supporting in view of the fact that the Sixteen Inch will be
the biggest telescope available in the Ottawa area and will
not cost more than 10% of a commercially made instrument of
that size because all the work is being done for nothing by
our own skilled members. But so far there has been no response
at all from this group.

The Fund stands at around $130 at present, sufficient
perhaps for a wooden mount of the lowest quality - one that
we would rather not start if we could start on something
better. If we could get the Fund up to about $400 we would
be able to tackle a mount of more lasting quality, and at
$600 we think a mount that is worthy of the Centre could be
engineered. This is not the season for Scrooges - give soon
and generously, and a Merry Christmas to you, too!
November 1, cloudy, 2 cloudy & rain, 3 the same; this
type of report goes on and on for at least eleven consecutive
days in November as all you amateur and professional
astronomers very well know. For a change all the coordinators
have the same complaint: "We were clouded out". It
was this phase that prompted me to find out that when
astronomers are clouded out they do one of the following
things: catch up on often neglected studies, improve or
modify their scopes, or read. It is the latter, with your
indulgence, that I would like to talk about.
The one place at both kinds of meetings of the Ottawa
Centre that generates its own cluster of avid followers is
the library. With such a large number of astronomical
books in one place, a person is often hesitant about what
book he would like to take out. Then on making a decision,
after much consultation, you find the book is out and has
been in the same hands for a number of months. No one
takes that long to read a book. This brings me to the
heart of this article. If there is enough interest I
would like to contribute a monthly report on books I have
read and new additions to our library.
While poring over the selection of books that Stan
Mott had just put away, Rick Lavery asked if I would like
to read a real good book. This proved to be "Starlight
Nights" an autobiography by Leslie Peltier. Not being too
impressed by the cover I made my first mistake; I started
casually reading the first chapter. The remainder of the
meeting was rather a loss as I couldn’t put the book down
for very long.

Mr. Peltier very quickly captivates the reader with
life on an Ohio farm just after the turn of the century.
From here he goes through the period of learning the sky
using what he calls "Friendly Stars" as guide posts. At
all times whether describing his merry-go-round observatory,
the thrill of "discovering" his first comet, or
hunting rock samples on his honeymoon he keeps the reader
to a sedate but interested pace in keeping with the times.
Mr. Peltier in his early years picked strawberries to
finance a modest 2-inch refractor at an astronomical price
of $18. For all of his 50 years of variable star observing
this $18 refractor was the only scope large or small that
he bought. The remainder came on loan from various institutes
and colleges. The book is a pleasant change from
excessive statistics - next time you are "clouded out".