AstroNotes 1973 April Vol: 12 issue 04

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ASTRO NOTES
Vol. 12, No. 4    April, 1973
Editor: Tom Tothill    22 Delong Drive, K 1 J 7E6
Addresses: Mary Grey    Dom . Observatory, 994-5474
Circulation: Ted Bean    399 McLeod Street, K 2 P 1A 5

EDITORIAL
Members of the Ottawa Centre have for years benefited from the aluminizing service provided free of personal gain by Dr. Lossing. Since North Mountain Observatory became established, its funds have received all the money resulting from a modest charge made to members for aluminizing their mirrors. Unfortunately, some members have been tardy in paying up for the service rendered and some arrears remain to be collected.

Let this be a reminder to them.

It would save a lot of grief if members were to pay in advance for aluminizing in future, and it is suggested that the charge be 'one dollar an inch'. However, if you think that means you can bring in your 200-inch mirror and get Dr. Lossing to do it for $200 you will have to think again! Also, you will have to be a paid-up member of the Ottawa Centre; too many 'maybe' members are using Dr. Lossing merely to save themselves the cost and trouble of commercial aluminizing services.
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Sorry, Astronotes still needs a new Editor.
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OBSERVERS GROUP MEETING - MARCH 2  Cathy Hall
Our March meeting got off to a good start with the presentation of the well-deserved Merit Awards, to Stan Mott and Ken Perrins. Congratulations!

Ted Bean, our Vice-Chairman, gave a run-down on the various activities and tours for the coming General Assembly. Note: you will not be sent info on the Assembly un­less you mail in the green centrefold (yes, Ottawa members too) of the last copy of the Journal.

Our new member and old-member-take-note (!) campaign was continued by Barry Matthews who spoke on the advan­tages of keeping a record of all your observations - i.e. who, what, where, when, what with. Who knows, we may breed another Tycho ...

Talking of new observers, we were treated to some very good hand-guided colour photos of Auriga, Orion, Gemini, and Coma, courtesy of Doug Welch, one of our soon-to-be-better-known observers. Keep up the good work!

A grazing occultation of Vesta is coming up! It's eighth mag and early in the evening. But wait - the battle with Murphy again - it's in broad twilight. Small scopes may have insurmountable difficulties.

Our planetary (etc.) shutterbug, Rolf Meier, has been at the camera again. Slides of the Horsehead Nebula (gasp!) the Whirlpool Galaxy, the Sombrero Hat Galaxy, and Comet Heck-Sause, adeptly re-located, were shown.... Oh, and Mars was mentioned too!

Next, up from good ol' Langrienus ... er, London Town ... appeared John Conville, one of our past coordina­tors, to talk on the variability of variables or "did you know there's something strange up there again?”

The logbook totals, and thus fee assessments for North Mountain for the coming fiscal year, were presented by Ted Bean. The most visits by one person - 75! - by none other than Rolf Meier.

Last, but by no means least, Allen Miller gave a talk on his newest creation - an 8 " f/11 Schmidt-Cassegrainian reflector, complete with scope on display.

Bulletin: Rumour has it that the beginners’ package (of useful charts, tables, "how to" items, etc.) is ready to emerge from deep space ... keep a watch out for it!
* * * * ***** * * * * * * * *
Come to the Gen'ral Assembly.
Watch Parl'ment inaction for free.
See Queen Juliana's nice tulips,
And try for a handout from DREE.
-Ed.

M81, M82   Rob Dick
These two galaxies, located in Ursa Major (the Great Bear) are a fine pair to view in binoculars or low-power telescopes. They belong to a loose group of galaxies and are around 7 million light-years away. However, where M81 is receding from us (red-shifted) at 88 km/sec, M 82 is receding at 322 km/sec!

The first galaxy, M81 (NGC 3031) is located at:
    R.A.    09 h
    Dec.     +69°5 1.5 m 18 '

It is an Sb type galaxy containing about 200 billion stars. The visual magnitude is about 8 and it measures 16 ’ x 10' (60' in a degree). Hence, of the pair, M81 is the more oval.
In comparison M82 (NGC 3034) is close by at:
    R .A.     09 h 52 m
    Dec.     +69° 5 6 ’

It is shaped like a cigar ( 7 ' x 2 '), and is slightly dimmer at 8.8 magnitude. Physically it is a much more interesting object. About 1 1?2 million years ago, a cataclysmic explosion shattered its nucleus, expelling matter equivalent to 5 million suns at 10,000 km/second.

Visually the object is quite mottled, possibly causing Hubble to classify it as a Type II irregular galaxy. He created two classifications for irregular galaxies: Type I contained resolved stars and structure (like the large Magellanic Cloud). Type II had little noticeable structure obscured by dust and gas.

Rolf Meier will show some photographs of these at the April meeting (I hope!).

The chart opposite shows how to find M 81 and M 82 . A diagonal across the bowl of the Dipper, extended about the same distance, will bring you within striking range.

COURSE FO R BEGINNERS  Dick, Hewitt-White, & Matthews

On the evening of March 16 , the threesome concluded their lectures for new members. The attendance was low, but this may have been due to a mix-up of dates.

The chief speakers were four of the coordinators. Rob Dick started with an outline of Deep Sky objects, ending in a barrage of questions, Jon Buchanan gave those present the low-down on variable stars. He discussed where to find them, how to observe them and what to expect, Barry Matthews took the floor to spread the word on lunar observing. And finally, although not presently a coordina­tor, Al Miller took up the topic of scopes and their use, notably the compound systems.

We wish to thank those who supported this, our second endeavour. Through the course of these lectures we have learned a great deal, and for this we thank you.

IN DARKEST FLORIDA  Fred Lossing

As part of a holiday trip to Florida in March, Tom Tothill and I took along my 8 " f/4.5 telescope, with the intention of observing and photographing some of the stellar and deep-sky splendours invisible from our north­ern latitudes. In the course of driving the interminable freeways, we managed to talk up the idea of photographing the Southern Gross as one of the objectives to be achieved.

The most northerly star of the Cross, gamma Crucis, is at Dec - 56 ° 57', and is therefore just on the horizon at latitude 33° 03', approximately the latitude of Charles­ton, South Carolina, The brightest star of the Cross, alpha, is however away down at Dec - 62 ° 56', becoming vis­ible over the horizon only south of a line through Palm Beach and Fort Myers. Even from the southern tip of main­land Florida, the complete cross clears the horizon by less than 2 °. Evidently we would need an unobstructed southern horizon, preferably over water and of exceptional clarity, if we were to succeed in getting a view and a picture of the complete Cross. Since ocean frontage in southern Florida is valued in megabucks per millimetre, finding unobstructed access to a dark area of Gulf Coast facing south was to prove to be quite a chase.

Our first try was on a convenient piece of island beach in a State Bark a few miles south of Fort Myers Beach, A preliminary daylight survey turned up a beautiful bit of flat beach, easily accessible by car, and a southern horizon masked only by some distant low shrubs. On returning after dark the situation still looked promising, and we drove down onto the beach and assembled the 8" scope. It was really peaceful, the sky was full of stars, the hori­zon was dark, the Gulf was calm, and we could hear only a faint sound of lapping water — as the tide rose stealthily toward our feet.

MY GOD, THE TIDE IS COMING IN! was followed by a wild scramble to slightly higher ground by both car and tele­scope, A new and, hopefully, tide-free position was chosen and after considerable digging in the sand to align the polar axis, our cameras were mounted and guiding began.

Now comes a wandering Volkswagen a deux, which after endless manoeuvring managed to conceal itself in some nearby bushes. Relaxing our defensive grip on the jack handle, we re-commence guiding. Now comes the State Police cruiser, flashing megawatts of light across the sand and eventually forcing the Volks back out of the bushes and off to more remote and uncontrolled areas (are there any?). Now comes the State Trooper: "What are you guys building the r e ? - - - - C.K., but no camping." and finally peace is restored. Guiding was re-commenced while Tom attempted to create a light-screen against the high-beams passing along the highway. Oh well, we'll try again!

Try Number Two was on a southward-facing point of land in the Bay of Naples (Florida) at latitude 26 ° 09', a quarter of a degree further south than Number One. Again we had a dark sky and a nearly clear horizon; plus (and occasionally minus) a party of friendly teenagers.

Three stars and a barely visible fourth of Crux gradually rose, and further pictures were taken. An absolutely overwhelming experience was the view of the famous glob­ular cluster, omega Centaurus, which at Dec -47° 09' was well up in the sky. Seen at medium power in the wide-angle ocular of the 8", this cluster was something to remember. It easily outshines M13, being one magnitude brighter and having an apparent diameter over twice as great. A prime focus shot of this was frustrated by a balky guide-scope. It was interesting to see the second brightest star, Canopus, at Dec -52° 40', with Sirius shining brightly halfway up the sky! The appearance of some clouds brought Try Number Two to a close.

Plans for Try Number Three were carefully laid, and a section of beach on the relatively unpopulated (so far!) Marco Island (latitude 25° 26 ') was found, with a minimum of arc lights and used-Cadillac lots, and an unimpeded horizon down to the water line. Aside from the inevitable curious night-watchman and his powerful headlight this proved to be the best yet: no ears, no mosquitoes, no fog, and no visitors. Our slides show at least 5 stars within the quadrangle of the Cross, but unfortunately Alpha Crucis, the lowest and brightest star, did not appear on film although seen from time to time in binoculars.

Several interesting clusters were also observed in 10 x 50 binocs and the 8", but identification was not possible since Tom's Norton had been lost at sea on Try Number One. Further views of the magnificent Omega Centaurus globular were obtained, and possible telephoto shots may be forthcoming. Following the culmination of Crux, a large constellation of many bright stars dominated the southern sky. Later checking showed this to be a real hybrid - Lupus, biting the hindquarters of Centaurus.

Toward 4 a.m. Scorpius and Sagittarius began to dominate the southeastern sky, and the Galactic centre west of Sagittarius was bright enough to appear like a patch of cumulus cloud. It is much brighter than the Milky Way cloud in Scutum. Finally, the Milky Way appeared as a bend nearly parallel to the southern and eastern horizons, all the way from the bottom of Centaurus, around through the tail of Scorpius and through Sagittarius, Scutum, Aquila, and Cygnus, fading down into the north-east.

A memorable night!
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VARIABLES ( 7 )  Jon Buchanan
A swirling mist of dense gas, fading out all but the brightest stars, of which refracting halo rings surround all but a few in rainbows of colour. Those few without a noticeable halo are immersed in wispy clouds of luminescing and reflecting gas. As if to acknowledge your presence one of the wisp-immersed stars flickers and brightens, then pulses several times while dimming several magnitudes, and continues to flicker almost imperceptibly as the wispy tendrils around it also dance to some unknown music.

This is one star of a new class of variables that we will look at now - Eruptive variables. The type of star I tried to illustrate above is a T Tauri variable, young stars of spectral classes F,G,M,or early M, having emission lines in hydrogen alpha and triply-ionized calcium, their light varies irregularly and unpredictably over a range of two or three magnitudes. These stars are found in enormous nebulae, and as such are thought to be new stars. There are over 200 in the great Orion Nebula, They are classed as Nebulous variables, with T Tauri as the prototype.

Now we travel to the other end of age, to the older stars. U Geminorum or SS Cygni variables have nova-like outbursts of as much as 5 magnitudes a night, which is smaller than nova outbursts. As such they are sometimes called dwarf novae. All of these stars are close spectroscopic binaries and though the intervals between the outbursts are not regular, they do not vary much, on either side of the average period. Such intervals can be from 20 to 600 days. They fade in days back to their minimum. Some typical stars, other than the prototypes, are HU Pegasi and X Leonis.

A group that is similar to these are Z Camelopardalis types, which experience standstills in which the light variations are suspended, sometimes as long as months. TZ Persei and RX Andromedae are other examples of this class.

An unusual type star that irregularly falls in bright­ ness is called an R Coronae Borealis type. Deficient in hydrogen but rich in carbon these stars range from G to R8.  SU Tauri and RS Telescopii are also such stars.

Getting back toward more nova-like behaviour we come to Flare stars. M type dwarfs, they brighten one or two magnitudes in seconds, remain at maximum from ten minutes to an hour, then slowly decline to minimum, UV Ceti, AD Leonis, and Proxima Centauri are examples of flare stars.

Next time we'll get into matter-ejecting eruptive variables,
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NEW OBSERVING PROGRAMS  Barry Matthews

Now that the beginners' course is over for the season and the snow is beginning to retreat to the Arctic, it is about time that observers started serious observing pro­grams. As New Member coordinator I have begun to dig into the past glories of the Ottawa Centre's observers. Did you know that the Ottawa Centre initiated a solar watch during the last sunspot maximum, took part in the last moon watch, reported on aurora, and counted meteors - just to name a few?

For this reason I would like to initiate two programs, one for the new observer, and then one with a little more challenge.

The first, to be called "Amateur Observer's Log B o o k ", has two purposes:
1. Get the observer outside, with or without a scope.
2. Get him or her into the habit of logging what they see and keeping records.

The rules are simple: Get outside, look, find, and log. Include such things as date, time, naked eye or instrument used. If a scope give size and power used, followed up with sky conditions.

e.g. Jupiter, March 20/21, 6 " reflector, 200x, clear.

A simple log sheet will be available at the next meeting. Here are some things to do:
- Identify some principal constellations! Big Dipper (Ursa Major), Orion, Gemini, Leo, Virgo, Cassiopeia.
- Identify the zodiacal constellations.
- Learn how to recognize the brightest stars: Polaris, Arcturus, Spica, Sirius, Betelgeuse, Aldebaran, Castor and Pollux, Capella, Vega, Deneb, Altair, Antares, Fomalhaut.
- Look at some double stars: Mizar (Alcor nearby), Epsilon Lyrae (the famous ’double double'), Albireo.
- Watch Algol go through an eclipse.
- Find and look at all the planets, except Pluto,
- Watch Jupiter's moons shift from night to night, and identify them.
- Watch a star occulted by the Moon.
- Project the sun's image and find a sunspot.
- Look at some star clusters! Pleiades, Hyades, the double cluster in Perseus (H-Chi) with binoculars.
- Put your scope on some bright Messier objects! M13 , M6 , M7, M11, M31 , M33 , M42, M44.
 - Log your first meteor.  Observe a major meteor shower.
- Look for an aurora, and try to sketch or photograph it.
- Identify two lunar ’seas’ (maria), A lunar mountain range. Find craters Tycho, Copernicus, and draw two others, Eratosthenes and Langrenus. Identify Mount Pico.

The second of my proposed programs is the more demanding, however, very simple to follow. I call this the "Observer's Messier List"; it is simply to find all the Messier objects. The rules are as follows:

1 . You must find the object by star hopping, not setting circles.
2. Describe the object verbally or in writing.
3. Photograph or draw the object.
4. Log the object on the lists to be supplied at the next meeting.
5. Turn in the list to the New Member coordinator.

Asteroids: Over the next two months the following aster­oids can be founds
(March)     Flora - 10th mag south of Tau Virgo.
(April)     Metis - 10 th mag south of M49.
        Eleanora - 10.6 mag in Coma Berenices.
        Herculina - 10.4 mag in Ursa Major.
        Pallas - 8 .8 mag in Serpens Caput.
        Thalia - 10.7 mag in Virgo.

Turn your reports over to Barry Matthews, who also wants astro photos of any area that has asteroids in it.
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THE SCHLOSSING SAGA (21)    Tom Tothill

"SIGNALS VERY WEAK
ARE YOU OK
FLOYD"

... wrote Schlossing instantly, the message having accidentally fallen upside down on the floor. Ah yes, he was catching up Floyd's last message again. Would he have to listen to everything over again - backwards?  Please, no!

ASTRO NOTES
TO
Ms. Rosemary Fr eeman
National Secretary
The Royal Astronomical
Society of Canada
252 College St.,
Toronto 130, Ontario.