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The Newsletter Magazine of the Ottawa Centre of the RASC
Vol. 24, No. 2 February 1984
Editor.......Rolf Meier......4-A Arnold Dr...... 820-5784
Addresses.... Art Fraser......92 Lillico Dr.......737-4110
Circulation...Robin Molson....2029 Garfield Ave...225-3082
OBSERVER’S GROUP MEETING - JANUARY 4
Chairman Doug George opened the meeting at 8:15 pm with 45 people in attendance, of whom 35 were members.
Centre president Brian Burke was up to say a few words on the next centre meeting on Solar VLBI (Very Long Baseline Interferometry) to be presented by Ken Tapping on January 22. He also mentioned that members should pick up a centre questionnaire at the end of the meeting, to fill out and return. This questionnaire will give the council some idea where interests lie in the Ottawa Centre.
He then talked about the need for rides to and from IRO and centre meetings to cope with the rising cost of gasoline, and about the need for bilingual people to help out in displays and observations.
Fred Lossing gave a talk on the famous double star Alberio in the constellation of Cygnus, and explained that these two stars are actually not gravitionally related but lie 580 light years apart.
Meteor coordinator Frank Roy spoke about the successful Quadrantid meteor shower he recorded with other observers. He had to place his observations between the setting of the moon and the rising of the sun.
Simon Tsang proceeded to present a slide and tape show on Voyager's explorations of Jupiter.
Sandy Ferguson was up to present a few types of variable stars and recommended R Leonis to new observers since it may be observed with binoculars. Sandy then
explained how to estimate the magnitude of a variable by selecting two or more comparison stars.
Next up was Gary Susick, to explain what to watch out for when taking astrophotos, and showed some slides of common mistakes.
Doug George was up again to display a new accessory that replaces awkward finderscopes. This new finder uses two AA batteries and has three glowing concentric circles in the field of view, ranging from 1/2° to 4° in diameter. It can be looked into from many positions since it is focussed on infinity.
Occultation coordinator Brian Burke announced two upcoming grazes in January and a favourable lunar occultation of a 2.9 magnitude star. Refer to page 85 of the Observer's Handbook for more information.
Doug George closed the meeting at 10:09 when people were offered refreshments.
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THE 1985 QUADRANTIDS FROM ARIZONA
Finally Ottawa too had an opportunity to enjoy the spectacle of meteors as never seen before. Again Arizona was very clear, somewhat cooler that last year, but not substantially. I was able to observe for an hour and remain comfortable.
The radiant of the shower at maximum was 15h 28m in RA and +50° in dec, with a predicted hourly rate of 40. The peak was to occur, in Arizona, at approximately 6 am MST. Perfect, we thought, as we started to observe at 4:50. The moon had just set, and it couldn’t have been timed better.
David Levy and I were the only observers this year, and they were prolific for us in Arizona as they were prolific for those who observed in Ottawa. These are the rates:
Linda Meier (facing N)
David Levy (facing S)
There may have been a few meteors that David and I both saw. But you can imagine how exciting it was to see so many in that time (one hour). That’s 143 meteors total in that hour!
During our final 10 minutes Rolf was looking up and noticed many meteors, including a number of non-shower meteors. You may recall from Dave Lauzon’s talk a couple of years ago that more meteors occur in the early morning hours just before dawn. So Rolf was really enjoying the show as it was 5:50 when we stopped observing.
Getting off the topic, I just want to add that we had many opportunities to see Comet Levy-Rudenko and that morning was no exception. On our last night in Arizona, on the morning of the 21st, we viewed it once again. It’s so remarkable how at each viewing this comet seems to change. It is now very quickly moving toward Ursa Minoris, and has become quite bright, as it can be seen in binoculars, and is rather large and diffuse with a bright nucleus. I know it’s cold and hard to get up early, but is is worth looking at...so get up, out, and find it!
David and Linda would likely have seen even more meteors, had they not also been busy recording their observations!
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RECENT METEOR OBSERVATIONS
On December 20/21, 1984, Doug George and I observed the U rsids from IRO. The skies were generally clear with a slight haze in the south, but the skies cleared at 22:30. The maximum was expected at 06h UT on December 22. This shower has a rather sharp maximum of only 2 days to 1/4 strength. Only 2 Ursids were seen in a total of 3 hours observing by Doug and me. Next year the Ursids will be on a new moon weekend, and maybe this year we will be luckier, but don’t bet on Murphy.
1985 must have been the year of the Quadrantids. Among 4 observers at IRO, over 400 meteors were seen from 4 am to 6 am local time, and the large majority of them were Quadrantids. I have been observing meteors for about 10 years now and never have I seen such a spectacular meteor shower.
The Quadrantids were expected to reach a maximum at 08h local time on January 3. The radiant at that time would be over 70° in altitude at our latitude. I noticed that the majority of the meteors were about magnitude 4.0 and peaked at about 5:30. By that time twilight was about to begin. Many bright meteors were seen, and Dave Lauzon claims to have seen a point meteor, that is, a meteor seen head on with no apparent angle.
I would like to thank Daniel Dlab, Dave Lauzon, and Doug George for making the effort to observe this unusual shower.
ROYAL ASTRONOMICAL SOCIETY OF CANADA
521-8856 Robin Molson
National Research Council
100 Sussex Drive
Topic: In cooperation with the Museum of Science and Technology, presentation of the film Professor Hawking's Universe. Professor Stephen Hawking, widely regarded as one of the most brilliant astrophysicists and mathematicians working today, established his reputation with his work on black holes, discovering that they are not necessarily black, and some of them even shine.
Although Stephen Hawking has fought for 20 years against the crippling disease amotrophic lateral sclerosis which confines him to a wheelchair, he continues his work on the unification of the two great but incompatible theories of modern physics, Quantum Mechanics and General Relativity. This film joins Stephen Hawking and his team of students at Cambridge University and through a student interpreter describes the quest towards ultimate knowledge.
The film will be introduced by Dr. Paul Feldman of the Herzberg Institute of Astrophysics, N.R.C.
Date and Time: Monday, February 18, 1985 at 8:00 p.m.
Place: Auditorium of the Museum of Science and Technology,
St. Laurent Blvd. and Russell Road
1985 METEOR SHOWERS
In 1985 there are 7 major showers yet to come which are well worth observing. Some of these occur on weekdays, but most of them are favouraby on or close to the new moon on a weekend.
There will be a meteor session for all of these showers at either IRO or Quiet Site, with IRO being the preferred location because of the significantly darker skies. Nevertheless, I will hold 1 or 2 sessions at Quiet Site. Transportation will be provided and more detailed information about these outings will be provided at the Observer’s Group meeting before the shower. The only requirements are perhaps a sleeping bag and warm clothing for those cool clear nights, but most importantly keen observers ready and willing to observe meteors.
The following is a list of showers, with moon rise and set times:
S Delta Aqu
This is for the meridian at Greenwich UT , in which case there is a slight error of a few minutes. The latitude is for 44°.
The Observer's Handbook 1985
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Articles for the March issue of Astronotes are due by February 15. Don’t forget that we now have the capability of reproducing photographs, through the services of member Roy Fox. Any print, colour or black-and-white will do. Show us your best astrophotos, pictures from meetings, star nights, projects, etc. This will really liven up our little publication, and give it a much nicer appearance. So do your best!
ASTEROIDAL OCCULTATION OVER OTTAWA
To observe this occultation you will not have to go far. The centre line for this event is a mere 8 km from downtown Ottawa. The details are:
date: March 4, 1985
time: 18:26 EST
duration: 28 seconds
star's magnitude: 8.9 (SAO 96887)
star's RA: 7h 23.0m
star's dec: 11° 36' (1950.0)
asteroid's magnitude: 11.2 (51 Nemausa)
magnitude change: 2.5
The only problem with this occultation is that it occurs when the sun is just 6° below the horizon. Evening twilight will not end until an hour after this event. Use the finder charts opposite to locate the star and to become familiar with the star field many days before the event. Ideally you should use a tape recorder and CHU receiver to record your observations.
* * *
THE GREAT HEXAGON
Many observers are familiar, with the asterism "the summer triangle", an easily-recogized group of three stars that dominate the summer sky. Now that the bright stars of winter are rising in the east, a winter asterism is visible.
Known as "the Great Hexagon" of winter, this group contains many of the winter’s brightest stars. You can trace the Great Hexagon by starting from the red star Aldebaren in the constellatin Taurus, high in the southeast. Looking north to the constellation Auriga, find the yellow star Capella and from there east to Pollux in Gemini. From Pollux look southeast to Procyon in Canis Major. Sirius, the sky’s brightest star, is south of Procyon and is in the constellation Canis Major. Looking northwest will bring you to the dominating constellation of Orion, and the blue-white star Rigel. Rigel is the right foot of Orion, the hunter. From Rigel you go back up to Aldebaren and complete the hexagon.
The red star Betelgeuse will be slightly south-west of the centre of the hexagon.
An asterism, by the way, is not a constellation but a group of stars that form a recognizable pattern, such as the Big Dipper, the Great Square of Pegasus, and the Summer Triangle.
c/o Herzberg Institute of Astrophysics
National Research Council of Canada
100 Sussex Drive