AstroNotes 1967 January Vol: 6 issue 01

EDITORIAL . Small Dome . Observers Group December Meeting . Deep Sky . Observer's Exchange . INDEX - ASTRONOTES - 1964 . Instrumentation

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AstroNotes

The Newsletter of the Ottawa Centre, RASC

VOLUME 6    ISSUE 1     JANUARY 1967

Editor : Dan Brunton 2565 E lm hurst S t r e e t , Ottawa 14 - Ontario . 8 2 8 -1 4 73
Circulation : Bill Dey 264 7 A yers A venue, Ottawa 8 , Ontario 733 -0 5 18

EDITORIAL

Our Centennial Year is finally upon us. I'm su re we have all waited eagerly for it and I want to wish everyone a most enjoyable and full year. With Canada's first 100
years behind us , the question of national unity and harmony is often debated . In my opinion a national birthday can't completely make a country united despite its tremendous impetus . it is the less grandiose functions , the behind-the-scenes co-operation that makes a country strong and united . I believe that the R.A.S.C. serves just such a purpose . The General Assembly, R.A.S.C. Journal and the various other organs of the society expose us to the ideas and opinions of our other members from coast to coast . it is just such contact, co-operation and communication that should make us proud of the R.A.S.C. and its purposes in the Centennial Year and years to com e. this couldd be our Centennial project: to establish even closer relations with the other centres of the R.A.S.C. so that we may learn more of their activities and efforts.

The second of 3 indexes for the various volumes of AstroNotes is included in this issue. The 1965-66 index will be in the February 1967 issue and then we should be
up-to-date. In future the index for each year should appear in the January issue of the following year.

Small Dome

Rick Salmon - Co-ordinator, Small Dome

Since there have been several nights (and a lot of film ) wasted in the past few months because of photos which were out of focus, a list of all focus positions so
far obtained for the scopes is given below .

SCOPE     FILM SIZE
4x5
4x5
4x5
8x10
8x10
8x10
4 x5
fa "
6"
Comet Camera
N o te: 1 .
4x5
4x5
4x5
SENSIT IVITY OF FILM
Pan
Blue
Red-Infrared (25A filter)
Pan
Blue
Red-Infrared (25A filter)
Pan
Blue
Pan
Blue
FOCUS POSITION
3 .7
3 .7
7 .9
1 0 .5
1 0 .5
14 .7
19.8
19.8
1 .4
1 .4

When using 4x5 film in the Comet Camera , an adaptor (usually left in one of the plate-holders) must be used to convert the plate size from 6.5 x 8.5 to 4 x 5.

2 . It is imperative that no one change the focus of the Comet Camera  as it would require further tests to re-focus it. One thing more to insure good results: on cold winter nights always check the sky for a low "cloud" about 10 degrees wide stretchi g from NW to SE over the Dome. This cloud is caused by steam from the chimney of a nearby building and without fail, it ruins the Zenith as far as photography at the Small Dome is concerned.


Observers Group December Meeting

The last meeting of the Observers Group was held on December 6 th 1966 and was attended by 32 members. At this meeting, our chairman announced that Tom Tothill, our Lunar Coordinator will be the Chairman of the Observers Group in 1967.

The committee for chosing the Member of the Year for 1966 was formed. It consists of Dr. Fred Lossing (chairman), Frank Evraire and Rick Salmon. We were warned
that all applications for the award must be received by the Committee by Jan. 20 1967.

Gordon Grant, our Radio Astronomy Coordinator, gave the Handbook Talk. He showed the members 1945 Handbook that he had and compared it to our present one. He also refocused attention on the construction of a simple sundial (see Astronotes: Vol.3 is s .6 and the R.A.S.C. Journal of February 1962).

Rick Salmon, our Small Dome Coordinator, showed the slides he took at the Algonquin Park Radio Telescope when he and several other members visited it in October.
The main talk of the evening was given by Jack Horwood, Satellite Coordinator. He spoke on variable stars (specifically eclipsing variables) and gave us a brief
history of Photometry. He explained the need for more observation in this field and suggested that the Ottawa Centre could do a lot with the facilities at our disposal.

As far as I know the earliest observation of Comet Rudnicki (E-1966) by the Ottawa Centre was December 4 1966 . On that night Rick Salmon and Dan Brunton photographed it with the 8" scope of the Small Dome. The Comet at that time was very dim (9th to 10th magnitude) and no tail was apparent. Unfortunately Comet Rudnicki arrive d on the scene too late for inclusion in the December 1966 issue.
* * * * * * * * * * * * * * * * * * * * * * *


Deep Sky

Frank Evraire

There are numerous constellations of interest this month, but I have chosen Taurus because I think it has more to offer.

Perhaps the best known feature of Taurus is the Pleiades, a star cluster. Photographic plates show that the entire cluster is surrounded by nebulous matter which
glows due to the tremendous energy which radiates from the starss within. The Pleiades, taken as a whole, are about 350 Lt.Yrs. distant and about 30 Lt.Yrs.
in diameter. The stars are enormous in size and inconceivably brighter than the sun, which at the same distance, would not be visible to the unaided eye.

There are more than 200 stars in this cluster and all are relate as they have a common motion and probably a common origin. The brightest stars in the Pleiades is Eta Tauri ( Alcoyne), magnitude 3 .0 . it is hundreds of millions of miles in diameter - a supergiant.

The names of the other stars that make up this lonely cluster are : Atlas, Pleione, Electra , Merope, Taygeta, Maia, Celaeno and Sterope. Each of these stars is at
least 800 times the size of the sun and the distance between each stars is about 4 Lt.Yrs.

Another cluster in Taurus (though courser than the Pleiades) is the Hyades. Because of the ir proximity to us ( 130 L t.Y rs), they appear widely separated . They also
have a common motion and are receding from us at a ra te of 25 M/P/S . While the stars that make up the Pleiades are generally blue in colour, those of the Hyades are red or yellow, and star-for-star, are quite a bit larger than those of the Pleides. They are not as bright however.

The brightest stars in the Hyades are estim ated to be from 50 to 100 times as bright as the sun. All the naked-eye starss in the Hyades are about magnitude 4 . The most interesting stars in this cluster is Theta Tauri, a near-naked-eye double, mag. 3 .6 and 7 .0 .The brightest stars in the whole constellation is Alpha Tauri, Aldebaran
magnitude 1 0 it is a navigational stars, has a d e fin ite red colour and is a mere giant, about 35 times the diam eter of the sun Aldebaran is chem ically of a type similar to the  sun but is much older. In sp ite of its age, Aldebaran gives off about 50 times as much light as the sun. It is not a member of the Hyades cluster as it is only about 53 Lt Yrs away. It also has a very f a in t companion of magnitude 11.2. Since Aldebaran lies well within the Zodiac, it is often occulted by the moon.

Finally north and east of Zeta Tauri is the first of those objects that caused so much annoyance to Charles Messier.I'm speaking, of course, of M1 the Crab nebula.


Observer's Exchange

WANTED: Degree setting circles with vernier scale
Contact: Rick Salmon
731-8427


INDEX - ASTRONOTES - 1964

A - EDITORIAL:

New editor, Astronotes - Vol. 3 is s . 1.
Galileo - Vol . 3 is s . 3
General Assembly - Vol. 3 is s . 6
Retiring President - Vol. 3 is s . 7
Stella fane - Vol. 3 is s . 7

B - Comets and Meteors:

1. Capricornid Meteor Shower - Vol. 3 is s . 7
2. Comet Everhart- Vol. 3 is s . 9
3. Comet Tomita-Gerber-Honda - Vol.3 is s . 7
4. Delta Aquarid Meteor Shower - Vol. 3 is s . 7
5. Lyrid Meteor Shower - Vol. 3 is s . 4
6. Perseid Meteor Shower - Vol. 3 is s . 7
7. Quadrantid Meteor Shower - Vol. 3 is s . 1

C - Deep Sky:

Algol - Vol. 3 is s . 9
Aquaris - Vol. 3 is s . 8
Canis Major - Vol. 3 is s . 2
Capricorn - Vol.3 is s . 8
Lepus - Vol.3 is s . 2
Monoceros - Vol.3 is s . 3
M-13 - Vol. 3 is s . 5
Ophiuchus - V ol.3 is s . 7
Orion - Vol.3 is s . 2
Pallas - Vol.3 is s . 5
Puppis - V ol.3 is s . 2
Sagittariu s - Vol.3 is s . 7
Scutum - Vol.3 is s . 7
3C-273 - Vol. 3 is s . 3.

D - Instrumentation:

1. Binoculars - Vol. 3 is s . 6
2. Resolving Power - Vol.3 is s . 1, 2
3. Scratched Mirrors - V ol.3 is s . 6
4. Sundial Construction - Vol.3 is s .6

E - Lunar:

1. Eclipse Observations - Vol. 3 is s . 2

F - Planetary:

Jupiter - Vol.3 is s . 8,9
Mars - Vol.3 is s . 8
Neptune - Vol.3 is s . 5
Saturn - Vol. 3 is s .8
Venus - Vol.3 is s . 2, 3, 5

G - Radio Astronomy:

1. Books about Radio Astronomy - Vol.3 iss . 3
2. Radio Astronomy with a television set- Vol. 3 Iss .

H - Solar:

1. New solar cycle - Vol. 3 iss . 1

I - Miscellaneous:

1: General Assembly - Vol 3 Iss 4, 5
2. Practica l Astronomy - Vol 3 is s . 8,9
3. Puzzles Vol. 3 Iss 1 , 2, 3
4. Puzzles answer - Vol 3 Iss 3
5. Stellafane - Vol 3 Is s 4
6. Recent Library books - Vol 3 Is s 5


Instrumentation

Gordon Grant

Sidereal Times for 19 00 hrs at Ottawa 1967 ( ± 0 5 min ) E .S.T.
Date
January
February
March April May
June
1
3
5
7
9 01
01
01
02
04 42
50
58
06
14 03
03
04
04
04 44
52
00
08
16 05
05
05
05
06 35
43
51
59
07 07
07
07
08
08 37
45
53
01
09 09
09
09
09
10 35
43
51
59
07 11
11
11
12
12 37
45
53
01
09
11
13
15
17
19 02
02
02
02
02 22
30
38
46
54 04
04
04
04
04 24
32
40
48
56 06
06
06
06
06 15
23
31
39
47 08
08
08
08
08 17
25
33
41
49 10
10
10
10
10 15
23
31
39
47 12
12
12
12
12 17
25
33
1
49
21
23
25
27
29 03
03
03
03
03 02
10
18
26
34 05
05
05
05 04
12
20
28 06
07
07
07
07 55
03
11
19
27 08
09
09
09
09 57
05
13
21
29 10
11
11
11
11 55
03
11
19
27 12
13
13
13
13 57
05
13
21
29
31 03 42
07 35
11 35

The previous chart is for the benefit of those who use telescopes with setting circles , Accurate sidereal time for dates not mentioned in this chart can be
determined by adding 4 minutes to the time for the previous date . The chart is set up for 19 00 hrs. , E.S. T. For example: to find the sidereal time for 9:30 p . m., E.S.T. on the night of April 8 at 19:00 hrs the sidereal time for April 8 is 8:05 April 7 + 4 min ) Therefore at 21:30 E.S.T. ( 9:30 p .m .) , the sidereal time will be 08:05 + 2:30 ; 10:35 hrs.