AstroNotes 1982 June Vol: 21 issue 06



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The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 21, No. 6 $5.00 a year June, 1982
Editor.............Rolf Meie r.............4-A Arnold Dr.......... 820-5784
Addresses.......Art Fraser.............11-860 Cahill Dr...737-4110
Circulation...Barry Matthews...2237 Iris S t............ 225-6600
On Thursday, May 20, Dr. D. Smellie spoke to the
Ottawa Centre at the la st lecture meeting of the spring at
the Auditorium of the National Research Council, 100 Sussex
Drive. His topic was "The Solar Corona", which consisted
of a reading of a paper to be published la te r this year.
The main aspects of the corona were described and current
theories were discussed.
In addition, Dr. Smellie outlined some current
activity in the investigation of geomagnetism. He
described the progress of various magnetometer designs over
the years.
In the question periods that followed, the
relationship between the two topics was pointed out.
Dr. Smellie is a former president of the Vancouver
Centre of the RASC, and presided when Vancouver hosted the
General Assembly in 1972.
Thanks go to Frank Roy for operating the slide
The regular series of Centre lecture meetings will
resume in the fa ll. Keep watching the pages of Astronotes
for notifcation of these events. Hopefully the
announcements w ill reach subscribers in time.
* * *
A rticles for the July issue of Astronotes are due by
June 18.
* * *
- 1 -Over the la st few weeks, several members have cleaned
up the site . This has included removal of the coffins
(which were 14 years old), a thorough cleanup of the inside
of the van, and cutting the grass.
As a result of these efforts, we were able to hold a
star night at the site on the night of May 21s t . About a
dozen people attended, and a number of telescopes were
brought. These included a 17 1/2-inch, an 8-inch
Newtonian, two Celestron-8's, and a refractor. The sky was
fairly clear, and the cool air kept the mosquitos away. In
fact, the sky was reasonably dark. Despite the growth of
the city of Kanata over the la st 10 years, the sky has not
suffered much. Deep sky observing was quite acceptable.
With the 17 1/2-inch, objects appeared much as they would
at IRO through the 16-inch on an average (but not
excellent) night.
As an added tre a t, hot dogs and soft drinks were
prepared on the site by Vice-Chairman Rob McCallum.
Donations were much appreciated.
Those attending w ill agree that the site offers good
opportunities for observers who do not wish to travel the
distance to IRO. I think we will see the rebirth of this
site as a major attraction for Ottawa Centre members.
Over the summer we will be having more star nights at
the site , and many more meteor observing sessions. And if
members wish to do some deep sky observing, they are
welcome to bring out their telescopes. It w ill probably be
easier bo convince a keyholder to drive out to the Quiet
Site than the Indian River Observatory. It should be
especially convenient for anyone living in the west end.
And even for east-enders i t is a shorter drive.
* * *
This year's Stellafane convention of amateur telescope
makers will be held on Saturday, August 14, on Breezy H ill,
near Springfield, Vermont.
Springfield is about a 7-hour drive from Ottawa, and
well worth attending if you are interested in telescopes,
and especially if you have b u ilt one. Many Ottawa Centre
- 2-members have won awards at Stellafane for their effo rts,
last year, Ottawa member Steve Dodson won an award for his
22-inch reflector, the largest one there la st year. Our
own 16-inch telescope won the third prize for optics at the
1971 convention.
There are several noteworthy points concerning this
year's Stellafane. Our own Fred Lossing will monitor the
afternoon talks, which include a presentation by our own
Ken Tapping. Ken w ill explain the relationship between
solar activ ity that can be observed by amateurs and events
on and within the sun.
The evening program will include a talk by Professor
Philip Morrison of the Massachusetts Institute of
Technology, his topic being "Quasars: Cosmic Jets and
Whirlpools". I would say that i t would be worth attending
Stellafane for that talk alone. Professor Morrison is a
well-known provocative speaker, and you've probably seen
him on television shows such as Nova. He is to cosmology
what Carl Sagan is to planetary studies.
In addition there w ill be informal talks on Friday
evening, and the judging of telescope on Saturday for
mechanical performance, and on Saturday night for optical
performance, as well as the opportunity to meet hundreds of
amateurs from a ll around North America and elsewhere.
* * *
An Introduction to Astronomy
by Frank H. Shu
1982, University Science Books, Mill Valley, California
584 pages
THE PHYSICAL UNIVERSE is published as a textbook for
an introductory course in astronomy at the university
level. Thus i t is written in much the same manner as you
will find most textbooks, with many nice equations, tables,
figures, and problems along the way as one reads the text.
There are also a large number of photographs, including a
section of 50 colour plates.
Being such a recent book, it contains what I judged to
- 3-be the la te st scien tific information about astronomy,
physics, and cosmology. At the current rate of increase in
man's knowledge of the universe, it is hard to say how many
of the facts will s t i l l be valid after 6 months, a year, 5
years, or even 10 years. One should therefore be cautious
in the interpretation of some of the rather tenuous data
now known about cosmology which Professor Shu has sometimes
unfortunately taken to be firm. However, in this he can be
forgiven, because this is sometimes necessary to get the
points of a lesson across.
The book covers many aspects of modem astronomy. The
la te st information from the recent interplanetary probes is
presented, including sane of the spectacular colour
phtotgraphs from the Voyager missions. A large portion of
the book is devoted to discussions of galaxies and
cosmology, an area a t present more void of facts than
theories. The science of physics is used liberally
throughout the book, particularly a t the nuclear level,
where i t is necessary to explain the supposed reactions
which occur inside stars. The text ends on a philosophical
note, with questions concerning the origin of life on the
earth, and its possible presence elsewhere in the universe,
Since this is university text, i t abounds with
equations. However, the use of calculus seems to be
avoided wherever possible, and most of the mathematics
should be readily understandable with a high school
education. In any case, the math is usually needed to
express a point.
Several topics were dealt with only superficially.
The section on telescopes was very basic, and did not
really emphasize the problems associated with making modem
astronomical observations, such as effects of the earth 's
atmosphere, light and radio pollution, and the advantages
of modern electronics. Also, asteroids and comets were
only briefly mentioned.
I think a new text of this kind should come out about
every year, to keep up with the la te st knowledge. With
this in mind, i t may be instructive to look back on this
book in ten years time, and see how much our perspective of
the universe has changed.
This book w ill be available in the Ottawa Centre
library, from Stan Mott the librarian.
Following on the next few pages are some illustrations
from THE PHYSICAL UNIVERSE An Introduction to Astronomy.
* * *
Figure 15.1. Deep galaxy map of a square section of the sky, 6°
on a side, made from data supplied by Rudnicki and colleagues at
the Jagellonian University in Cracow. The average galaxy among
the more than 10,000 counted may be located between two and
three billion light-years away in this map. Notice that the
distribution on this scale is almost random, in contrast with
Figure 14.6. (For details, see Groth, Peebles. Seldner, and
Soneira, Scientific American, 237, May 1977, 76.)
5Figure 14.6. A photographic representation of the ShaneWirtanen counts of galaxies. Individual galaxies are not shown.
Instead, each small square bin is intensity-coded to represent the
number of galaxies found in that boxed area of the sky. Clustering
is apparent to the naked eye, as is verified by a detailed analysis
of the positions of the million galaxies that have more than a
minimum brightness. (From Seldner, Siebers, Groth,and Peebles,
A. J., 82, 1977, 349.)
Figure 16.19. The annihilation of two good friends, one of which
happened to be made of matter, the other of antimatter.
c /o Herzberg Institute of Astrophysics
National Research Council of Canada
100 Sussex Drive
Ottawa Canada
K 1A 0R6