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The Newsletter of the Ottawa Centre, RASC
|Vol. 13, No. 4 April, 1974|
Editor ..Rolf Meier 77 Meadowlands Dr. W..
Addresses.... .Earl Dudgeon...545 Bathurst Ave.....
Circulation...Ted Bean.......399 McLeod Street.....
• • • • •
• • • • • K2G 2R9
In a book on optical instruments, I found a spectrum of the response of the human eye. What struck me was the composition of the lens or cornea and the functions of the various parts of the eye. In humans, the eye is one of the parts to develop first, reaching a size of about one inch in diameter early in life. It is made up of concentric spheres, which become thinner as you approach the front.
The outer sphere, or SCLERA, is the white part of the eye and thins out towards the front where it clears to form the cornea. Inside this is the CHOROID, which carries the blood about the eye, keeping the temperature constant, and maintaining the cells. It is dark in color, which prevents
scattering of light inside the eye. The front of the choroid is the iris which regulates the amount of light that enters the eye. At night it opens to as much as 7.5 mm and during a bright day it may close to 2.5 mm, or 3 f/stops.
The inner sphere is the RETINA, which is made up of the receptors of the eye which allow you to see. These receptors consist of rods and cones. The cones sense color and the rods sense black-and-white. (intensity). These rods are used to look at dim objects. They are more sensitive to light but lie around the edges of the eye, decreasing in number as you approach the center, where the cones are most abundant. Hence the reasoning for averted
vision. By looking to one side of a dim object, the light would fall on a more sensitive portion of the eye. The lens is made up of two parts. There is a crystalline lens inside a membrane-like-bag made of fibers which slide over each other, deforming the lens shape. The refractive index varies across its section, from 1.373 at the edge to 1.420 in the center. This aids focusing. The cornea absorbs shorter wavelengths of light (ultraviolet)
which aids the color correction.
The eye is made up of parts which are comparable to refracting telescopes. Further study into the make-up and operation of the eye will lead to new insight into how to look at objects and how reliable your observations are.
OBSERVERS GROUP MEETING - MARCH 1
The March meeting began with an invitation to the 55 persons present to attend the General Assembly, this year to be held in Winnipeg June 28 to July 1. Rolf Meier commented on last month's lunar grazing occultation. Murphy had struck once more. Although conditions looked favourable, haze blocked out the 8.9 magnitude star at the crucial moment.
Barry Matthews spoke briefly on occultations. Unfortunately the Saturn occultation was also hit by misfortune.Although we've been blessed with some beautifully clear nights lately, it seems that every major event has been heralded with clouds.
Cathy Hall anounced the star party held at North Mountain observatory on March 22. (see the report else where in Astronotes. -Ed.) Cathy's talk was highlighted with slides of North Mountain and Quiet Site.
Quiet Site? Last year we observed just over 400 meteors according to Chris Martin. Such a low tally has presented some consternation among observers. Although several new faces had been seen around the site during the summer, it appears that the cold winter scared off even the most ardent supporters of the Quiet Site.
Doug Somers presented some slides of M 44 and the Great Nebula in Orion.
Fred Lossing closed the evening's matters with the second in his series of talks - "What Does Light Tell Us?". Enthusiastic response to the talk was evident by the many and varied questions following the talk.
The planet Jupiter returns to viewing position in the morning sky this month. Watch for the mutual phenomena of the satellites, the last of which take place next month.
OTTAWA CENTER MEETING - MARCH 14
Our guest speakers for this month were Dr. J. Popelar of the Earth Physics Branch and Mr. J. Kouba of the Geodetic Survey of Canada who spoke on applications of artificial satellites. The theory behind the calculation of orbits and positions was discussed, as well as the more practical details of tracking and control. Following this, the many and varied uses of satellites were delved into in some detail. The talk concluded with a brief discussion period, where some interesting questions were raised. Thank-you, Dr. Popelar and Mr. Kouba, for an interesting technical
THE STAR LOST - A GRAZE REPORT
by 2 unknown members
Based on the Northmountainburg Trials of Graze Criminals A permanently borrowed Cablevision van streaked toward the county line, followed in heavy pursuit by a squadron of police cars. "Five-O!" they yelled, but Jon Buchanan floored the pedal. The gears were ground to dust, but the van relentlessly pushed on. With the tires shot out, a hole in the roof, and no signal indicators, we turned into the vast expanse known as Northmountainville.
Suddenly, the van screeched to a halt, the inertia carrying Doug Somers' mirror forward through the diagonal. As the edge of night swept through Northmountainville, Jon turned on the headlights, and lo and behold, there was Rob Dick in his Silly Suit with matching hat and beard. He was standing near a billboard which had "Welcome to the Graze" flashing in bright neon letters. Behind him was the desolate road with its snow, dust, potholes, and tumbleweeds.
Presently, Rolf Meier, the Tundra Rat, drove up in his winterized staff car. "You guys take position one!" he yelled. Jon Buchanan cried "We want a stake." "Make it medium rare" cried Doug Somers, and was promptly rammed down his telescope tube. By now, Rolf had disappeared into the wilderness.
Position one was half-way home, but we set out after getting the van (which only travels in reverse) out of the snowbank. Doug Somers' telescope had been ruined by the potshots from Chopper One. Meanwhile, Jon Buchanan was listening to a Jello festival in Rumania on his short-wave radio while hunting for CHU. All of a sudden, a pair of red bloomers emerged from the darkness, and the person holding them was Chris Martin.
The star to be grazed could not be found. Chris made some "helpful" remarks and was immediately rendered unconcious. A hue and cry of "Its not there!" arose from the crowd. Within minutes, Chief Tundra Rat Meier and special agent Rob McCallum, graze analyst and color commentator, arrived to check on why the star was gone. Rolf ruffled through the mile and a half of computer printout on grazes, while Rob McCallum combed the area.
"Well?" we queried, but Rolf Just stood there stroking his chin and staring at the moon. "This could be profound!" he yelled, and disappeared
before we could get a word in edgewise. The time for the graze had come and gone. While Doug Welch continued to watch out for the star, Jon explained to his tape recorder that it wasn't his fault, and if he had had his way he wouldn't have come. We all then headed for Station 2, where the gallows were located.
The crowd, all hot and bothered, stood around waiting for Rolf to arrive. Then a voice in the distance cried, "It was all a Joke, the graze is really tomorrow, ha ha."
Rolf Meier was tried and convicted of:
Intent to kill by freezing
Allowance of a dangerous vehicle at a public gathering
Intercounty transportation of permanently borrowed telescopes
Intercounty transportation of stolen steaks
Many minor misdemeaners
He was sentenced to 99 years as graze coordinator but his sentence was reduced to 2 years for having the good taste to use a Dodge staffcar in his getaway.
The events you have Just read are based on actual incidents. The locations and names have not been changed.
Heavenly Bodies Anon Astrom
or “Streaking" Comes to North Mountain
(Howard Harris presented . . . an interesting slide of Dr. Lossing "au naturelle". Astronotes, March 1974)
We've observed that a heavenly body
In the "sixteen" can look pretty gaudy;
But with modesty shed,
An "au naturel" Fred
Is not so much gaudy as bawdy.
On the other hand, if you happened to look up the
alternative in your Funk and Wagnalls:
I'll tell you a tale that's unvarnished,
Of a wit whose stale puns became tarnished;
His companions, irate,
Chopped him up on a plate,
And served him up cold and ungarnished.
A FUNNY THING HAPPENED ON THE WAY TO NORTH MOUNTAIN or HOW TO HOLD A STAR PARTY WITHOUT STARS
by one who went
It all started at the Geophysical Building on the evening of March 22. OK, forward, hoooo! Four cars following ours, others already enroute. Hogsback. Company, halt! Three cars...oh well, the wagon train heads south. Nearing North Mountain now. Car check. Two cars.. ..oh wait, there’s the third - in the ditch. Everybody out - push, stop, push. OK, we’re out. Only another mile, and we’re at the star party!
Hey! The parking lot is shovelled out! Spring had arrived, along with Glenn Slover, Walter Turner, Rob McCallum, and a snowblower. Thanks guys' Well, we pulled into tho OK Corral, donned our zoot suits, and headed out into the wild dark yonder. People, people everywhere, and not a spot to think.
Would you believe 30 people and 14 cars? Really. Even the great Zeus could not recall such a multitude in recent months. Neither could Murphy.
There rages a great debate as to the bringer of those great and ominous clouds. Was it the presence of so many meteor coordinators in one spot at the same time? Or was it that the great sky god didn't like being spied upon by no fewer than 11 telescopes?
In spite of adversity, a number of objects were indeed accounted for - M 42, M 44, M 45, M 81, M 82, M 97, M 108, Saturn, and about 3 dozen hotdogs and cups of hot chocolate. No casualties were reported.
Present were such infamous characters as "Big Jon” Buchanan of Circle J, Cut-throat Chris Martin, the "Meteor Rustler", Art "the Dart" Fraser, Rolf "Tundra Rat” Meier, Lester of the Macdonald gang, and Doug of Welch's Gulch. And, of course, the Northmountainville gentry were there - acting mayor Schlossing, Bedlington Tean, Sheriff "Be Prepared" Matthews, and Deputy "dippity" Dave Fenchuk. Last, but not least, we should mention "Silly Rob" Dick, the town fool.
Star light, star bright, stars that disappeared tonight...Oh well, back to the ranch Sam. We'll try again next month!
Doug wishes to make the following elaboration on a statement made in February Astronotes (A Constellation Review):
If the visual spectroscope is made so that the light from every star in the field is shown as a small thin spectrum, then a planetary would surely stand out, if some chemistry is known by the observer. "Joe Observer” knows that when a slit spectroscope is used, the lines of the spectrum are images of the slit formed by the different refractions of luminous elements. If a star is observed in a visual spectroscope, it shows a long, thin, continuous spectrum. In visual spectroscopes the dispersion usually isn't great enough to see absorbtion lines, so the spectrum appears continuous. Each color is an image of the star in that particular light. However, the light from a planetary nebula is the result of ionization of rarefied gas by ultraviolet radiation from the central star. Most prominent are the "lines" of doubly ionized oxygen at 4959 Å and 5007 Å . These "lines”, being very close together in the green, show a green image of the planetary nebula (in a visual spectroscope) among all the other continuous spectra from stars in the field.
In this way, the image of the planetary nebula is unchanged and stands out easily in the most crowded star fields, and permits the observer to use higher power knowing which "star" in the field is actually the planetary.
A CONSTELLATION REVIEW (7)
Douglas Welch, Douglas Somers
This month's article is on the constellation Sextans. It is a fairly large constellation located beneath Leo. There are several interesting objects located here:
NGC RA DEC MAG SIZE
2967 09h 39.5m +00 34' 12.4mpg 2.2'x 2.0
2974 40.0 -03 29 11.0mv 1.5 x 0.9
2990 43.6 +05 57 13.0mpg 1.0 x 0.5
3044 51.0 +01 49 12.6mpg 4.6 x 0.5
3055 52.7 +04 31 12.6mpg 1.7 x 1.0
3115 10 02.8 -07 28 9.3mv 4.0 x 1.2
3156 10.1 +03 22 13.1mpg 1.0 x 0.5
3166 11.2 +03 40 11.4mv 4.4 x 1.7
3169 11.7 +03 43 11.7m v 4.0 x 1.7
3423 48.7 +06 07 11.5mpg 3.5 x 2.8
The first 5 are all very faint objects, not being marked on the Skalnate atlas. However, 2974 should be within the reach of a six-inch scope under good conditions. NGC 3115 This is definitly the best galaxy in Sextans. You should have heard the remarks of one person I showed it to. My notes say "FANTASTIC, very elongated, very bright central core, faint extensions heading northeast and southwest, resembles M 31 with binoculars, seems to be much larger than telescope can show, again like M 31, wonderful eight in 16-inch." No Messier observer should pass this one up.
NGC 3156 Normally I would not observe objects as faint as this but having a 16-inch around I decided to go after it. Another criteria is that it is within a field of the two brighter galaxies that will be described presently. All of these galaxies are actually considered a group. There is a fourth but it is about 16th magnitude! My recommendation concerning this 3156 is to forget it. It is about 14th magnitude visually.
NGC 3166 and NGC 3169 These galaxies are in the same field and are relatively bright. They look almost identical in all respects. There are plenty of stars around in the field. 3169 has a star very close to its core (what I regard as the core). They are a good pair and can be seen in a 6-inch.
NGC 3423 My first comment was that it looks like Comet Kohoutek! There are no distinct features about this galaxy at all. It resembles an unresolved globular cluster. On some really clear night in the country this could be visible in a 6-inch.
Here I would like to take an opportunity to give an explanation of why we give these articles to our readers. We have reed many catalogs and short descriptions of objects located everywhere in the sky. They all almost always are descriptions done a long time ago by an advanced amateur and nothing new had been done since. We also found only one comprehensive book on descriptions covering the entire heaven's objects and this was done by observations with a 6-inch refractor.
We set out to get a fresh point of view of every object in the sky over a period of years with only our descriptions.
Ken Hewitt-White and Allen Miller did one for the summer skies and we don't intend to trespass on their territory. However, in the cloudy months I was unable to get in contact with Douglas Somers and read the article he had written, so it went to press. Most of these have, unfortunately been copies out of handbooks and no observing (or, like the Andromeda article, no credit for observing) was made. We would especially like to humble ourselves about the Aquila article which was copied straight out of a book. We have resolved to never do anything like it again.
The Editor will not be responsible if contributors submit articles as their own material which are not.
RECENT IAU CIRCULARS
Another comet for binoculars anyone? It seems that Comet Bradfield, 1974 b, may be just that. It has now passed perihelion, its closest approach to the sun, and is moving steadily upwards in the western sky after evening twilight. On April 1, it will be at magnitude 5.9 in the constellation of Triangulum, reaching Perseus by the 13th at magnitude 7.4, and Cassiopia by the 23rd at magnitude 8.6. A table of revised coordinates follows. (c.2642)
Comet Bradfield. 1974 b
Date RA Dec mag
April 1 2h 20.09m 30° 43.6’ N 5.9
3 2 22.41 35 53.1 6.1
5 2 24.32 40 45.7
7 2 25.88 45 19.0 6.6
9 2 27.17 49 32.2
11 2 28.25 53 25.5 7.1
13 2 29.18 56 59.7
15 2 30.00 60 16.4 7.6
17 2 30.78 63 17.2
19 2 31.54 66 03.9 8.1
21 2 32.35 68 38.0
23 2 33.20 71 01.1 8.6
On February 20 (before perihelion), a magnitude 8 was reported, with a tail of about 3’ in length (c.2640). On the night of March 19 I had no difficulty in spotting Bradfield with 8 x 30 binoculars, just down from Alpha Pisces. It had about a half-degree tail. The predicted magnitude was about 4.8, although I couldn’t verify this due to a slight glow along my western horizon.
Still on comets, Kohoutek is being mentioned frequently - and its doing the unexpected again. An antitail was reported on Feb. 9, of about in length in 25 x 105 binoculars (c.2634). On Feb. 22 the antitail had faded considerably compared to Feb. 13, but it brightness relative to the main tail had greatly increased. So much was the increase that on Feb. 24 the antitail was brighter than the main tail (c.2643). The IAU circulars state that its presence points towards the existence of meteoroids 0.5 mm and larger, ejected before Dec 23, and that its persistent appearance indicates continuous high production of heavy particles before perihelion. There is also reason to believe that somewhat smaller particles were emitted for several days before perihelion (c.2637).
I was rather pleased to find out that there was indeed a bright antitail on Kohoutek. The reason? I took a 34-minute guided exposure on High Speed Ektachrome on Feb. 15/16 and found Kohoutek at about 11 mag....and a double tail...and an antitail! All with just a camera.
Another comet up-and-coming is Comet Encke, at about mag. 10 on April 3, in Aries, and getting brighter. Unfortunately, the brighter it gets, the earlier in the evening it sets, as it is approaching perihelion. However if you have a telescope of any size, give it a try. The coordinates for the first part of April follow (c.2547).
Date RA Dec mag
April 3 1h 53.01m 17° 26.0' N 10.2
8 2 11.76 18 38.5
13 2 32.53 19 42.6 9.0
Lastly, it was noted that one of the satellites of Saturn, Titan (VI), has been detected as brighter than normal, at magnitude 8.28, as compared to previous values of 8.30 in 1973, 8.35 in 1971, 8.37 in 1970, and 8.39 in 1961 (c.2628). Reasons for such a phenomenon were not given.
(c.nnnn) indicates the IAU circular number. -Ed.
Articles for the May (100th) issue of Astronotes are due by April 19.
Ms. Rosemary Freeman RASC
The Royal Astronomical Soc. of Can.,
252 College St.
TORONTO 130, Ont.