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The Newsletter of the Ottawa Centre, RASC
|Volume 6 Issue 6 June 1967|
Editors Dan Brunton 2565 Elmhurst Street, Ottawa 14, Ont. 828-1473
Circulations Joe Dafoe 2366 Malone Cresc., Ottawa 5, Ont. 828-7681
This is rapidly becoming an extremely busy year for everyone. What with Centennial and an ever increasing number of enthusiastic observers, it is very difficult for we poor editors to keep up! It certainly is fun trying, however! Doug O'Brien is one of the worst "offenders". At his present rate of winning awards, we will have to double the size of Astronotes to do justice to his evergrowing list of citations and achievements! In all seriousness, however, Doug has done very very well for himself and I know we all want to join in congratulating him most heartily on a job well done!! His latest achievements ( and what achievements!) are documented as completely as possible on page 9.
You will have noticed the article on pages 3,4 and 5, by Mr. Malcolm M.Thompson, President of the RASC. Normally an article of that length which is to appear in Astronotes, would have to be cut rather drastically, but considering the excellence of the article and the fact that Mr.Thompson is our President, that just would not be right! His article is a continuation of our policy to print, when possible, the talks presented to the Main Centre, for the benefit of those who cannot make these meetings.
The Centennial General Assembly is now over and I hope everyone had a good time. Unfortunately, due to the time when Astronotes has to be ready and also due to the fact that there will be no regular summer issues, a report on this event will have to wait until our first fall issue. I will not be in Ottawa this summer and so the Centennial Summer Issue will be put out by someone else in the group. I will be here until approximately the 20th of this month, so those who wish an article published in the Centennial Issue (i.e. the co-ordinators) can still get it to me before that date and lessen the work for whoever will be putting out that issue. I am glad to accept articles for the fall ( and any other) issues of Astronotes now or at any time. I already have received two articles for our first fall issue and if they are any indication, it will be a good one.
Have a happy Centennial June and good seeing.
The Centennial Project - Aug.26 to Sept. 4 Tom Tothill, Chairman, Observers Group
The Centennial Project which we have been planning for some time will be a camping trip to Point Petrie , near Picton, in the last week of August and including the Labour Day weekend. An easy drive from Ottawa, Point Petrie is as far south as we can conveniently get without going quite a long way west or leaving Canada. It is also far from any major city or highway glow.
We have made arrangements with Mr. Clarence Tripp, whose farm is on the east side of the road to Point Petrie about two miles from the end, to use a large well-drained field. It contains a very few trees but otherwise the view is unobstructed in all directions. He will provide some necessary amenities ( ladies and gents) and we will probably be able to run a modest power line ( for telescope drives only) from his barn.
There are beautiful beaches, lavishly equipped with change rooms, picnic tables, etc. within a few miles. One can hire boats, horses, and if the worst comes to the worst, even cottages in the vicinity. For those who tire of camp cooking, there is even a hotel which does a superb smorgasbord on Sundays, with live organ music!
The Prince Edward Peninsula also boasts a Lake on a Mountain (possibly a crater) and plentiful fossil deposits. The Bay of Quinte on the north side is a yachtsman's paradise and the ferry across it to Picton is free as well as frequent. We aim to be up all night whenever it is clear, observing and photographing everything of astronomical interest. It should be possible to see quite a piece of southern sky which we ordinarily miss.
We also hope to build an all-sky-camera ( simply a driven frame on which everybody's camera can be mounted, pointing in different directions) and to line up campfire talks for cloudy evenings. It is hoped that everybody who possibly can will participate. The more experienced observers will be able to guide those who are new to the art, and we all hope to expand our knowledge quite appreciably. It is not necessary to have elaborate equipment - binoculars or a camera can be very useful - but I hope that those who can't make it will consider lending their telescopes to careful applicants. We also hope that those who can't come for the whole week will come down for the Labour Day weekend.
There will be a special issue of Astronotes in August ( though it looks as if Dan Brunton won't be here to prepare it) containing data on the astronomical phenomena observable during The Week. Co-ordinators are requested to start now to build up a table of events in their fields; this may entail some research in the Ephemeris
and other publications, and time is needed to assemble and print the final version.
This could easily be a week we will long remember with affection and possibly with pride. Its success depends largely on your enthusiasm and preparation. Members from other Centres who may chance to read this are cordially invited to join us. There is no charge except for modest camping fees.
Scoreboard ( game still in progress)
The weather 1 1
Grazing Occultation Team 0 0
Observers Group May Meeting
Our May meeting, held on the 6th with 31 members in attendance, got under way at about 8.30 p.m. It began with Tom Tothill speaking about the Centennial Project. There then followed a spirited discussion on the idea of an all-sky camera for use at the Picton site. Rick Salmon and Peter MacKinnon volunteered to look into this possibility. Plans for a June meeting were also discussed.
Rick Lavery then exhibited his newly completed RFT telescope and gave a talk on variable stars. Tom Tothill prompted another interesting discussion on the idea of changing the present system of measuring angles; instead of 90 degrees for a right angle, 100 grads would be representative. This conversion to a metric system is aimed at greatly simplifying our present method of angle determination.
( As I was unable to attend this meeting, I am very grateful to Rick Lavery for the information used in the previous article. ED)
Keeping Canada On Time Malcolm M.Thompson, President, RASC.
How did Canada become interested in timekeeping? It will be recalled that British Columbia, as a condition for joining Confederation in 1871, asked that a railway be built to link east with west. A right of way through the mountains was made available, and this had to be surveyed. Both latitude and longitude of points along the route had to be determined by astronomical methods. Latitude presented no problem. Anyone of several known stars, when observed during transit will give a measure of latitude by combining the tilt of the instrument with the declination of the star. They will also provide an accurate measure of local astronomical time; and all that remains in the longitude problem is to compare the local time at two places in order to measure the difference in longitude. Harrison provided the solution in 1760-61 when he carried his
chronometer to the New World and back and made a direct comparison between Greenwich time and the local time at Jamaica. The longitude difference was determined with an error of 18 miles.
In the survey of Canada, an observer at Ottawa and an observer at a western site would determine the local time using the same set of stars on the same night. Part way through the night they would compare their two chronometers by telegraph communication. Before the telegraph line was completed across Canada, some of the western positions along the railway line were tied in to Seattle and later referred to Ottawa. The railway survey was completed in 1885. Ottawa, of course was the reference meridian, and here a permanent little observing hut was established on the banks of the Ottawa River, behind the present Supreme Court building. As a by product of measuring astronomical time for survey purposes, this small observatory provided mean solar time for a few government offices.
Dr. King, the Chief Astronomer, and a distinguished surveyor, realized the need for Canada to do more than bread-and-butter astronomy. His quiet persuasion resulted in the construction of the present Observatory on the high ground of the Central Experimental Farm. Not only was it equipped to study the sun ( coelostat) and stars ( 15 inch equatorial) and the geophysical phenomena of gravity, magnetism and seismology; it was also equipped with an up-to-date time service. The observing instrument was a
Meridian Circle, which is really just a large transit telescope. Its peculiar characteristic is that it is mounted on a horizontal axis accurately aligned east west so that the telescope can point only in the plane of the meridian. Stars are observed during the brief interval of meridian passage. A precise astronomical clock is used to measure the time between successive stars and a large graduated circle attached to the telescope indicates the tilt of the instrument and hence the declination of the star.
So the time service was equipped to assist in the international program of mapping the sky. Certain of the stars observed each night were well known, and their times of
transit were used to check the time of the master clock.
By the 1930's, it was found that time determinations could be made more effectively with a small transit telescope which could be reversed in its pivots halfway through the transit of each star. So there was division of labour, one telescope to map the sky, and one to measure earth rotation, and hence astronomical time. Mean solar time is very easily computed from sidereal time because of the well established ratio of 365.2422 to 366.2422, there being one extra sidereal day during the interval required for the sun to make its annual journey around the earth.
The precise astronomical pendulums maintained accurate sidereal time from one night's observations to the next, and mean solar clocks were regulated from them. The night by night comparison of time between Ottawa and a field party required a permanent connection from the Observatory to the telegraph office. This led eventually to the feeding of a time signal each day to each telegraph company, a signal that is carried on their lines from coast to coast. A better known service is the noon signal which is transmitted each day by the C.B.C.
Wireless communication which developed during World War I, was used in two capacities by astronomers. The field parties used it to compare their chronometers with Observatory time, and the Observatory itself used it to compare time determinations with other national observatories. Field parties in Canada commenced using wireless in
the early 1920's, demonstrating that it was no longer necessary to restrict operations to locations fed by telegraph. Time signals emanating directly from the Observatory commenced as an experimental operation during the 1920's. Later the three frequencies, 14.670 MHz, 7.335 MHz and 3.33 MHz, were registered with the call sign CHU. Today CHU provides a 24 hour service with a bilingual announcement of time each minute.
By the mid 1930's two developments of interest had an impact upon the Observatory time service. Clocks controlled by quartz oscillators were demonstrating a performance superior to the pendulum. And a new observing technique was making the simple transit instrument obsolete.
The old time room with its pendulum clocks and its banks of relays for transmitting second pulses was a work of art. Supposing there was a clatter bang of clicks and thumps, and supposing radio interference was noticeable blocks away, at least one could watch the pendulum in fascination. Furthermore only battery power was required to keep the pendulum operating for years ( barring an. earthquake).
The first quartz frequency standard arrived in 1941. After the war others were added, and by 1951 the last pendulum clock was withdrawn from service. The quartz clock has the advantage of a better rate because it is not subject to disturbances due to earth vibrations. Also the quartz oscillator is capable of subdividing the second into very tiny portions such as milliseconds, tenths of milliseconds, and even to fractions of a millionth of a second. So the quartz clock has proved to be an indispensable tool for laboratory measurements.
In the early 1950's the small transit telescope was replaced by the new photographic zenith tube (PZT). It may be programmed to operate independently throughout the night. The small plate of stellar images, when measured, gives astronomical time with ten times the accuracy of the transit observations. In addition the PZT observations give a night by night value of the local latitude which varies slowly through the year due to motion of the pole of rotation.
It was the combination of precision quartz oscillators and improved observing techniques that demonstrated not only that the earth was varying in its speed of rotation in a random manner, but the amount by which it was varying. Since the unit of time, the second, was tied by definition to the mean solar day, it too was varying and was no longer a valid fundamental unit. It should be mentioned that these variations have no effect on the accuracy of longitude measurements as they were conducted on a differential basis. In 1956 the Internationsl Astronomical Union defined the unit of time as 1/31,556,925.9747 of the mean solar year 1900. The laws of mechanics permit this to be carried forward and backward in time. An observation of the moon or any of the planets can be interpreted into a value of time. Since the moon has the greatest apparent motion through the stars, it has become the hour hand and the starry b ackground is the celestial clock. One sweep of the moon is accomplished in about 27½ days, so it cannot be read at any one time with very great accuracy. A year of observations are required to measure the time difference between this new time, called Ephemeris Time, and mean solar time to a fraction of a second. Amateur observations of lunar occultations are a distinct contribution.
The first atomic resonator, which was the forerunner of the present day atomic clock, was built by Essen, of the National Physical Laboratory, England, in the early 1950 's. In collaboration with Markowitz of the U.S. Naval Observatory, a callibration was made of the frequency of the observed transition with respect to the ephemeris second, and was found to be 9,192,631,770 ± 20 cycles per second. There have been strong urgings to define the ephemeris second in terms of the caesium transition frequency. Very wisely this has been resisted for two reasons, one, that there was insufficient evidence that the first measurement was correct, and, second, there is a distinct possibility that a superior atomic clock can be built using another element such as hydrogen.
As the earth varies in its rate of rotation, so does mean solar time. However for the purposes of navigation, surveying, and all activities requiring a knowledge of the rotation of the earth with respect to the stars, a knowledge of mean solar time, and hence sidereal time, is necessary. This is accomplished by operating the atomic controlled clock at a definite frequency offset. Regular star observations
provide a day by day indication of the relation between the computed and the observed time. When the difference amounts to one tenth of a second, then on the advice of the Bureau International de l 'Heure, the national time services make a step adjustment at the beginning of the next month. If the rate of the atomic controlled clock needs
adjusting, it is done by international agreement at the beginning of the year. A rate adjustment was made at the outset of 1966, but no change was necessary for 1967. At
the moment the output of the clock is running slow by 300 parts in ten to the tenth ( about 2.8 milliseconds per day) compared to its natural rate. The atomic clock
serves as two clocks, first to indicate ephemeris time, and second to indicate mean solar time. During the 67 years since the turn of the century, mean solar time has lost
about 37.5 seconds . There is no good explanation for the loss, nor any indication when the rate will change.
Canada's time service is monitored by an atomic clock. By international agreement the time pulses of all the national time services are synchronized to one thousandth of a second.
Timekeeping has advanced into the atomic age. It is still pleasant to look at the sundial and contemplate.
Solar Rick Lavery, Solar Co-ordinator.
Information is just now reaching me concerning solar activity. To
begin with let me recall a sentence in the April issue of Astronotes concerning
February's Spot Group, "This spot, however, was 1/7 - 1/8 the diameter of the sun or
approximately 100,000 miles across. It contained over 50 spots." It turned out that this
estimate was quite accurate as "Sky and Telescope" gave a figure of 130,000 miles across
and about 200 individual spots. The latter figure shows how better resolution and higher
power can affect observations. Doug O'Brien reported the great increase in solar flare
during the passage of the Group, just prior to the beginning of his solar monitoring.
Upon the sunspot group's return on March 20 it had dramatically rearranged itself into
1 main spot about 30,000 miles in diameter and intricate penumbral and umbral details
following behind. I worked out the spot's rotational period to 26.5 days, but due to bad
weather I missed its reappearance on April 14th. and it wasn't until April 16th at the
"Quiet Site" when some of the Small Dome's Senior Observers and I observed it with the
4" Unitron we had just installed. The Spot had decreased its diameter greatly and by the
time it had reached the limb, it was no larger than most other spots. Whether or not this
is an epitaph wasn't known until May 12th.
As I have said before this solar maximum might prove to be very active.
The February group was the biggest since November 1960 and on March 25th we had the
largest solar flare since June 4 1946. With this much activity on the sun and the days
getting longer I hope more people will take the opportunity to observe it. Below is a
summary of observations for the first 4 months of the year.
Instrumental - Doug O'Brien with his equipment and the radio telescope at the "Quiet
Site” monitored solar noise during March. Ralph Hutchison is working on
equipment to be used at the "Quiet Site" with the radio telescope and
Photographic - Les MacDonald was the only one to obtain any results of high standard
when the February Spot Group appeared. Photos were taken on 3 days in the
"solar snowdrift" during February and early March. ( For further details
on the "solar snowdrift" see Astronotes, Vol.6 Iss.4 . April 1967.E D)
Naked eye - This is a field in which many people could participate as it takes very
little time. All that is required is a sun-filter, a few precautions
and two minutes of your time. Peter MacKinnon, Rick Salmon and Tom
Tothill observed a naked-eye group this way on March 16th.
Telescopic - The above mentioned and possibly a few others, observed the Spot Group
through optical instruments of some sort. However, John Lindeyer of the
Hillcrest astronomy group has been regularly observing the sun for the
AAVSO. The following is a list of observations made by the solar coordinator
for the first 4 months of 1967:
Average Sunspot number
8 8 . 1
Aurora - The only reported aurora from the Ottawa Centre comes from Peter
MacKinnon on March 18/19 and from Dan Brunton on May 6/7. If there have
been any other occurrences besides these dates please report them to me.
During the summer I hope to interest more people in naked-eye sunspot
observing and develope a system for direct photography of the sun with my telescope
which will supplement and eventually take over my visual sunspot observation. By the
time of our Centennial observing trip I hope to have the foregoing established and when
we are at Picton it will give a chance to everybody present to learn something about
solar observing in d etail.
Ottawa Centre Library List Stan Mott, Librarian
- B - Telescopes, Optics, etc.
1. The Amateur Astronomer and His Telescope ( 1963) Roth
2. Amateur Astronomers Handbook ( 1958) Sidgewick
3. Amateur Telescope Making, Book 1
4 . Amateur Telescope Making, Book 2 ( advanced) (1954)
5. Amateur Telescope Making, Book 3 ( 1956)
6. Astronomical Photography ( 1961) de Vaucouleurs
7. Astronomical Telescope at the Telescope (1961) Rockham
8. Astronomical Spectroscopy ( 1961) Thackeray
9. Binoculars and All-Purpose Telescopes ( 1964) Paul
10. Frank's Book of the Telescope ( 1959)
11. Frank's Book of the Telescope (196k)(fifth edition)
12. Handbook for Telescope Making (1962)
13. The History of the Telescope (1955) King
14. How to Make a Telescope (1957) Texereau
15. Making Your Own Telescope (1947) Thompson
16. Cuter Space Photography for the Amateur (1961) Paul
17. Outer Space Photography for the Amateur (1963) (revised) Paul
18. Practical Amateur Astronomy (1963) Moore
19. Radio Astronomy for Amateurs ( 1962) Hyde
20. Space Chemistry (1963) Merrill
21. Standard Handbook for Telescope Making (1959) Howard
22. Telescopes (1961) Kuiper and Middlehurst
23. Telescopes and Accessories Dimiteoff and Baker
24. Telescopes for Skygazing (1965) Paul
25. Tools of the Astronomer ( 1961) Miczaika and Sinton
1. Between the Planets ( 1941) Watson
2. Between the Planets - Revised Edition (1956) Watson
3. Comets and Meteor Streams ( 1952) J.G.Porter
4. The Comets and Their Origin ( 1953) R.A.Lyttleton
5. Earth, Moon and Planets ( 1941 ) Whipple
6. Earth, Moon and Planets - Revised Edition (1963) Whipple
7. Meteors( 1963) Millman and McKinley
8. Meteor Astronomy ( 1954) Lovell
9. Meteors, Comets and Meteorites (1964) Hawkins
10. Meteor Science and Engineering (1961) McKinley
11. The Moon ( 1958) Wilkins and Moore
12. The Moon - Earth's Natural Satellite (1967) Branley
13. The Moon, Meteorites and Comets (1963) Middlehurst and Kuiper
1 4. The Nature of Comets (1963) Richter
15. Neighbours of the Earth (1965)
16. The Origin of the Solar System (1966)
17. Our Sun (1963) Menzel
18. The Photographic Story of Mars (1962) Slipher
19. A Photographic Study of the Brighter Planets (19 6 4) Slipher
20. Pictorial Guide to the Moon (1963) Alter
21. Pictorial Guide to the Planets (1965)
22. The Planet Jupiter (1959) Peck
23. The Planet Mercury (1963) Sandner
24 . The Planets (1962) Moore
25. The Planet Saturn (1962) Alexander
26. The Planet Uranus (1965) Alexander
27. The Planet Venus (1961) Moore
28. Satellites of th e Solar System (1965) Sandner
29. Solar Research (1962) Abetti
30. The Story of the Moon (1943) Fisher
31. The Sun ( 1963) Abetti
32. The Sun and the Amateur Astronomer (1963) Baxter
3 3* Surveys of the Moon (1963) Moore
3 4 . The System of Minor Planets (1962) Roth
35. Wanderers in. the Sky (1965)
- Stellar Astronomy and Cosmology
1. Changing Views of the Universe (1961) Ronan
2. Fact and Theory in Cosmology (1961) McVittie
3. Galaxies (1961) Shapley
14. Galaxies , Nuclei and Quasars (1965) Hoyle
5. Guide to the Stars (1960) Moore
6. The Hubble Atlas of Galaxies (1961) Sandage
7. The Milky Way (1941 ) Bok and Bok
8. The Milky Way (1957) Bok and Bok (revised)
9. Nebulae and Galaxies (1964) Abetti
10. Stars in the Making (1952) Payse-Gaposhkin
11.The Story of Variable Stars (1945) Ca mpbell and Jaechia
- E - Historical, Biographical and Miscellaneous
1. The Astronomers ( 1964) Ronan
2. Exploring the Planets (1964) Firsoff
3. Discovery of the Universe (1957) de Vaucouleurs
14. The History of the Telescope
5. Starlight Nights (1965) Peltier
6. Stonehenge Decoded
7. Watchers of the Skies (1963)
8. 1963 Yearbook of Astronomy
9. 1964 Yearbook of Astronomy
- F - Atlases
1. Atlas of the Heavens - Skalnate Pleso
2. Atlas Coeli Skalnate Pleso II
3. Bonner Durchmusterung
4 . Norton's Star Atlas (1959) two copies
5. Photographic Lunar Atlas
6. Stern-Atlas I - Vehrenberg
7. Stern-Atlas II - Vehrenberg
8. Webbs Star Atlas
* * * * * * * * * * * * * * * * * * * * * * *
Radio Emissions from the Sun at 210 Megacycles Doug O'Brien
The purpose of this project is to determine whether a connection exists
between the number of sunspots and the V.H.F. radio emissions from the sun. A 210
megacycle receiving and recording apparatus was constructed and used in conjunction with
a 20 foot parabolic antenna system belonging to the Defence Research Board. The apparatus
was built mainly from old television parts adapted to this new use. Observations have
been made over several weeks.
On March 23rd two enhancements in background noise are observed at
13:45 EST and 14:33. Coincident with these enhancements are major and major+noise bursts
observed at 184 MgHz by independent sources which probably co-relates with an important 2
flare which started at 19:23 hours U.T. This solar noise activity is confirmed by N.R.C.
This study is not conclusive in an attempt to find a co-relation of the
occurrence of radio noise enhancement for several reasons. The data has been accumulated
over a very short period of time with very few events being recorded, and hence no
meaningful analysis can be performed. The second reason is that the equipment is very
low and some lesser solar events may be buried in receiver noise. Thirdly, the preliminary
results from the N .R.C . solar radio observatory show a very low level of solar activity.
The instrument I used is basically a receiver, A dipole, through
matching devises, feeds my 210 MgHz converter which is a modified television tuner. I have
re-aligned it to function best just off chanel 11. This unused area of the television
band gives me little interference from commercial broadcasting. My tuner is directly
connected to a broad-band I.F. amplifier and this is coupled to a tuned I.F. amplifier
salvaged from junk. After detection, the signal is again amplified and fed into a
photographic recording d evise which I salvaged and reconstructed from an ancient
electrocardiograph. The instrument was slowed down to 1 ½ inches per hour and produces
photographic records of the sun's activities from dawn to dusk. A timer cuts out the
active parts of the receiver at sunset and reactivates them at sunrise.
Although the sensitivity of the receiver is low, I have detected major
solar bursts. Results from previous sunspot cycles have shown that a co-relation exists
between major solar burst activity, flare activity and geophysical activity. It would
appear therefore that meaningful studies could be carried out which corroborate the
co-relations between major burst, noise activity and geophysical phenomenon.
1. Antenna System
3. 210 MgHz Tuner
4 . I.F.Amplifier
7. Damping Capasitor
10. Power Supply
Editor's Note: You will remember that Doug entered the Ottawa Regional Science Fair
last year and won 1st prize in Physics and $100. Representing Ottawa
at the National Science Fair that year, he was also awarded a
proficiency award (with $10.) and the Bronze Medallion of the Canadian
Aeronautical and Space Institute.
The Previous article is a summary of Doug's project in this year's
Science Fair. In the Locals he again finished 1st in Physics ( and
another $100.). Here, he was awarded the Bronze Medallion of the
Canadian Aeronautics and Space Institute and a plaque from the Institute
of Electrical and Electronic Engineers and an additional $50.
The big difference this year was in the National Competition. Doug
finished 2nd in Canada in Physics, a wonderful achievementi Another
$5 0 . went along with this honour.
He has done extremely well and I know we all join in extending
heartiest congratulations on his splendid effort. You can all appreciate
how much Doug deserved these commendations, upon reading his article.
Such awards aren't earned by luck and Doug certainly worked for them!
Again, congratulations Doug and best of luck in next year's Fair!
ATTENTION!! The annual Stellafane meeting (number 27) will be on August 5th this
year. For details, contact Tom Tothill (749-4723) or Gordon Grant
Miss Ruth J. Northcott,
252 College St.,
TORONTO 2b, Ont. RASC