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The Newsletter of the Ottawa Centre, RASC
|Vol. 13, No. 1 Vol. 13, No. 1|
Editor.... ...Rolf Meier...77 Meadowlands Dr. W ., K2G 2R9
Addresses.... Mary Grey....Dominion Observatory, 994-5474
Circulation...Ted Bean 399 McLeod Street, K2P 1A5
At the time of this writing, the great Comet Kohoutek (Ko'-hoe-tek) has been seen and has once again disappeared into the morning twilight. It has been very disappointing that it has not as yet been seen by the naked eye, despite ideal conditions. The comet is much fainter than predicted, and so far it has not even matched Bennett's brilliance in 1970.
The public has been deceived, and they will not probably be treated to the phenomenon of the century. It may be the flop of the century. But, not to worry. We can tell the general public that they were looking in the wrong place or the wrong time, if they report that they can't see it.
Things may still change. The comet will be more favourably placed for viewing in the evening sky, and the tail will in any case be longer. The comet may indeed be much brighter after perihelion, if its close passage to the sun causes structural changes. On the other hand, we may be looking at an object which is in reality very rocky, with some cometary material on the outside. Thus, at great distances it would behave like a large comet, and create erratic predictions.
Consider the amazing circumstances surrounding the discovery of the comet. Kohoutek was actually looking for asteroids, which he believed
to be the remnants of the disintegrated Biela's comet. In the same field where the asteroids were expected to be, he found not one, but two
comets, 1973e and 1973f, eight days apart!
OBSERVERS GROUP MEETING
Ted Bean opened the l- asDtE Cm.e7 eting Coaft hyt heH all year with the announcement that centre newsletters such as Stardust, Skyward, and Nova are being received. If you are not regularly getting Astronotes, let him know.
A number of coming events were mentioned by Karl Poirier, including the lunar eclipse on Dec. 9, Saturn occultation on Dec. 10, and the
solar eclipse on Dec. 24. He also talked of progress at the Quiet Site. A new communication panel has been installed in the van.
Slides of the Nov. 10 transit of Mercury were shown by Doug Welch and yours truly. Doug also talked on his pet interest, asteroids, and
offered coordinates to those interested.
Have you seen Comet Kohoutek yet? Rolf Meier showed a number of prints to illustrate its development. He appeared on CBC's "This Day"
on Dec. 21, when he discussed the prospects for this comet. Besides comet photography, he has just finished construction of a special base
for one of the Centre's meteor cameras, and hopes to get an efficient baseline system working soon.
Still on meteors, Chris Martin gave a few words on the recent showers observed - and not observed. Keep your fingers crossed that Murphy will blow away with the next blizzard! If it is clear though, and you need a ride, give our info centre a call at 733-1931.
New faces continue to appear. Ian Ross, a teacher at Algonquin College, showed a very nice print of the June 30 solar eclipse, taken on the
shores of Lake Rudolf. He also had some shots of the transit, taken with a 3 1/2-inch Questar. Thanks for some interesting photos!
Lastly, elections were held. The results are as follows:
Chairman......... Ted Bean
Recorder...... ...Holly Allan
Coordinators will be appointed by these three people as they see fit.
COMPARISON OF B&W FILMS
Well at last our program has gotten off the ground and the first two of perhaps a zillionand-a-half tests has been cataloged. Ilford's HP4 and Agfa's Agfapan 400 were compared. While the major details of the tests are being withheld until some sort of final report is ready, suffice
it to say that a test target was photographed under identical conditions and the pictures also printed under identical conditions. Also the
star field around Mars was recorded on both films, with identical exposures, etc.
The results of this first test indicate that some valid conclusions can be made. Ilford claims that their emulsions are very thin and would result in less back-scattering of light. This was evident on the photographs of Mars. The star trail pictures show Mars to be a large blob of equal size on both films. However, the Ilford print does not exhibit the bright ring around the planet to the same extent which the Agfa print does. In fact, in comparison to the Agfa print, this ring simply does not exist on the Ilford print. It would appear that extensive testing will have to be performed to determine which is the better film for astronomical prints.
The test target revealed that even though the Ilford film was pushed to ASA 650 in Microphen, it had substantially better (smaller)
grain size than the Agfa film. Further types of developers will be used on the Agfapan in the hopes of reducing its grain size. The Agfa film
had by far the better contrast of the two. This was verified on the test target and the Mars photograph as well. The next step is to push
the Agfa film to a higher speed and leave the Ilford film at its normal ASA 400. After that, these films will be further compared to Tri-x.
Don't forget about the annual dinner meeting, to be held on January 15 in the RA Centre.
TO DRAW THE PLANETS
As was mentioned in previous articles,"the solar system is the training ground for the Universe". You will recall that I am an advocate of the use of the pen and paper in recording the ever-changing moon. These techniques can be as easily applied to the planets. To record the alterations in the inner and outer planets you need nothing more expensive than paper, pencil, and an eraser. The time taken to record the planets is never wasted, for every drawing made at the telescope has trained your eye to see.
To the observer on earth, the planets are easily divided in two groups: Mercury, Venus, and my beloved moon (inferior); and of course the remaining planets are the superior planets.
I intend to first discuss our inferior friends, Venus and Mercury, as these I feel are by far the hardest and require the utmost discipline.
Venus is the most difficult of all planets to observe and it is sad that this bright shining gem is easily drawn. What appears to be a near perfect drawing when shown to the seasoned observer is shreaded with overly kind words. Even perhaps of losing these old and young beginning observers never to return to the astronomical community.
The only thing that appears to have to be done is to prepare a 2-inch blank with the phases drawn in. Remember that you cannot see the pole, so this does not have to be shown.
First you record the phase ana then by the skillful recording of cloud formations. The most important thing to remember is record only what you are sure of. You cannot put down on the paper the things your mind things you see.
Note the positions of the cusps, limb brightenning, and cusp caps.
Remember, you are your own worst judge.
THE SCHLOSSING SAGA (26)
I t was Boirier who, having re-activated the Dish1 , was the first to regain contact with Schlossing.
Astronotes is privileged to be able to record verbatim for posterity the epoch-making conversation that ensued:
Schlossing had had one anxious day keeping watch for the Great Mirror in the Sky, but didn't see it and obediently made his One-eighty when the System told him to. Since then he had been decelerating back towards Planet Earth and was currently threading his way through the asteroids,
with AVOID giving him a jolt now and again, and big black things going by his window like an inverse camera shutter.
Pretty soon Bedlington Tean came on the line via the Dish, with questions about his fuel level and other technical matters, and the entire Ground Organization was set in motion once again. He repeatedly tried to contact Grady Grunt by radio, but was still too far out for the hams to pick him up. The photographers on the Super Sixteen tried long exposures on his part of the sky but his exhaust - by now practically down to "idle" - was far too faint to register.
"The System isn't programmed for Re-entry, Red," Tean explained, "We couldn't be sure of exact timing and fuel level. But you look in good shape to come on in without re-fuelling." "Great!", said Schlossing, "I wasn't looking forward to weightlessness." "Oh, you'll have to have some of that.
We've got to incline your orbit for splashdown. Besides, we've got to locate you and time you to know when splash will occur."
"Where is splash, anyway?" "Lake Ontario. The Minister of Pollution won't let us bring you in dry."
1and became a father in the process? "I'm dry all right. My tongue's hanging out. Who says I am polluted?"
But there was no reply.
Barry Matthews still needs eyepieces for the Japanese size scopes. If you have any, please call him at 829-7237.
If you are observant, you will notice that this issue of Astronotes seems to be different. There are two reasons for this. First of all, the type is different because a different typewriter was used. Secondly, it is rather shorter than usual. No satisfactory reason has been found for this so far.
Date RA Dec Elongation
Jan. 3 19h57m 17°29m S 15.7°
4 20 8 16 42 17.7
6 20 33 15 5 21.7
8 20 56 13 24 25.6
10 21 20 11 37 29.6
12 21 43 9 44 33.6
14 22 6 7 47 37.5
16 22 29 5 49 41.4
18 22 51 3 51 45.1
20 23 12 1 56 48.6
23 23 41 0 46 N 53.4
26 00 08 3 13 57.4
29 00 32 5 23 60.8
Feb. 1 00 54 7 15 63.4
4 1 13 8 52 65.5
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