Buying your first telescope in Australia

Don't buy a coat-hanger!

Although lawyers won't let me mention the names of the manufacturers on this site, Department Store Telescopes are easily recognized by the outrageous lies printed on the packaging (or in the catalogue); such as: magnify up to 600x, see trillions of km into space, see spiral galaxies and nebulae -- in short, implying that you will see as much detail as the professional observatory photos on the box.

What they don't mention is that the 600x image will be a useless blur (assuming the telescope stops wobbling for long enough), that most of us can see things thousands of lightyears away with the naked eye (for example the Large Magellanic Cloud at 190,000 lightyears), and that professional photos go much fainter than the eye can see. Furthermore, the optical quality of these wallet-slimmers is questionable. I personally have seen $500 Department Store Telescopes outperformed by $80 finder scopes!

If you're wondering "how do they get away with selling this junk?" the short answer is that most buyers (and sellers) don't know any better! One manufacturer was convicted of misleading telescope advertising in the English courts a few years ago; but as far as I know no-one has been prosecuted in Australia. Buyers who know better, buy a better telescope in the first place.

Some (not all) Department Store Telescopes can be improved with good eyepieces and a stable mount. If you have gone out and bought one of these things in ignorance (or you were given one as a present), see my suggestions for improvement.

There are only four things you can use an unimproved Department Store Telescope for:

• as a low magnification finder scope (on a real telescope), or
• a coat-hanger, or
• a door-stop, or
• to support tomato bushes. Enough said...

Aperture

Optical designs

• The refractor; which is a long, relatively thin tube (about 10 to 15 times longer than its diameter), with a big lens (the objective lens) at the top end; and the eyepiece at the bottom end. Usually, the eyepiece goes into an eyepiece diagonal (an accessory which turns the light through 90 degrees) to permit comfortable viewing. Unfortunately, an eyepiece diagonal produces a reversed or mirror image of the "direct" view. This can be a real problem for some people when trying to match what they see with what is charted.

  Really cheap refractors may have an objective lens consisting of a single piece of glass (or plastic!). Avoid these -- they produce images with garishly coloured haloes. You should buy a scope with an "achromatic" or "apochromatic" objective. Achromatics use two pieces of glass (one behind the other) in the objective lens, apochromats use three pieces of glass. Both will focus all the colours of light to virtually the same point, which gives you a better, brighter image.

  Recent developments in optical glass technology -- the so-called "ED" lenses -- allow refractors to be made shorter than ever before, while still providing proper colour rendition and sharp images. The tube can be as short as 5 times its diameter.

• The reflector; which is an open tube with a big, slightly concave mirror (the primary) at the bottom end; a small flat mirror (the secondary) inside the top end, and an eyepiece sticking out the side of the tube at the top end. The image is the same as the "direct" view, but may appear to be rotated. This is not a problem when using starcharts, because the chart can be spun around to match the telescope view.

  One problem with larger reflectors is the height of the eyepiece. You may need a strong free-standing ladder to reach the eyepiece when the telescope is pointed high in the sky. But any telescope that big will also be hard to transport.

• The catadioptric or Schmidt-Cassegrain; a fat tube with a window-like lens (the corrector plate) covering the top, a concave mirror in the bottom end, and a hole through the concave mirror leading to an eyepiece sticking out the bottom end. The secondary mirror is usually supported by the front lens. Catadioptrics often have eyepiece diagonals too, leading to the same image reversal problems as the refractor. A variant on this design -- the Maksutov -- uses a strongly curved corrector plate (it looks like a bubble).

Telescope optics do (occasionally) need cleaning. Descriptions of how and what you can (and can't) clean at home are available.

Better telescopes are frequently described as "diffraction limited". This means that in perfect observing conditions, the clarity and resolution of the telescope's images are constrained only by the laws of optical physics. This image illustrates what a diffraction-limited image of a single star looks like through a refractor.
A reflector's image is similar (provided its secondary mirror is not unduly large); but you may also see evenly-spaced "spikes" emerging from the image of a bright star. This is normal for a reflector. A Schmidt-Cassegrain's image does not have these spikes.

Of course what you see in the eyepiece is a tiny version of this image -- I've greatly magnified it here!

The Airy rings are an example of a diffraction pattern; caused by the light from a point source -- the star -- being perceived via a circular aperture. The circular aperture in this case being the objective lens or primary mirror. Read an introductory physics book for an explanation of diffraction)

To the experienced eye, the size, shape, spacing and relative brightness of the Airy rings (and the star image) provides clues to various optical defects, focusing problems; and the atmospheric conditions. An adequately illustrated discussion of this topic would overflow my website, so you won't get it here ;-) But I do have a few notes on optical problems.

Mounting designs

• don't wobble (or collapse) when bumped,
  
• don't let the telescope move in a breeze,
  
• don't need to be aimed several degrees above (or below) the target to compensate for their "flabby" mechanical behaviour,
  
• do have smooth, balanced, controllable movement around their axes of motion,
  
• do support the telescope safely in any position,
  
• don't rust, bend, break or wear out components after a few hours of use.
  

There are two major species of telescope mountings:

• alt-azimuth; which has a vertical (azimuth) and a horizontal (altitude) axis. Easy to aim (just point the tube at the target), but tracking requires simultaneous motion on both axes. At high magnifications this can be difficult even with a good quality mounting and slow-motion controls.

  A variation on the alt-azimuth design -- the Dobsonian mounting -- is commonly used for larger reflectors and home-made telescopes. The Dobsonian rotates (in azimuth) upon a large baseplate, and the baseplate supports two uprights with semi-circular cutouts. The telescope tube is mounted (rather like an old cannon) between two large circular bearing surfaces resting in these cutouts. Here are some schematics for making your own Dobsonian mount.

• equatorial; which has a Polar and a Declination axis. The Polar axis has to be made parallel with the Earth's axis; by tilting it to match your latitude, and aiming the top end southwards (or northwards for Northern Hemisphere users). This is called Polar Alignment and doing this properly requires time and patience. It is particularly difficult in the Southern Hemisphere because there is nothing bright to aim the Polar axis towards. Polar Alignment is also a nuisance if you have to carry the telescope from storage to an observing location each time you use it.
  But once it is set up properly; an equatorial telescope can track targets by rotating on its Polar axis alone -- a job easily done by a motor drive -- which makes it ideal for photography or high-magnification observing.
  A good procedure for Southern Hemisphere Polar Alignment is available from the Deep-sky Observer's Companion. Another description can be found here.

  However, many beginners are baffled by equatorial mounts; and are bewildered by the (sometimes peculiar) manoevures needed to aim in some directions. The eyepiece can also end up in some awkward positions.
  Two common variants of equatorial mounts are the German, which features a counterweight on a bar opposite the tube; and the Fork, which has the tube supported between two thick arms emerging from a turntable-like assembly. Fork mounts are common on Schmidt-Cassegrain telescopes (eg: the larger Meade and Celestron models).

Elaborations to both types of mounting include slow-motion controls, setting circles, computer readouts or controls, clever precision engineering, and semi-automated polar alignment. All of these things add to the cost of the telescope.

Poor mountings are a universal characteristic of Department Store Telescopes, but they can (sometimes) be replaced with something better. See my suggestions.

Magnification isn't everything

It is possible to engineer most mechanical and optical problems out of a telescope, which is why a good quality scope costs a lot. However, engineering out the instabilities of the Earth's atmosphere requires adaptive optics - which cost a huge amount of money. The Earth's atmosphere is rarely stable enough to permit useful magnifications beyond about 250x; especially if you are observing from metropolitan areas.

If it's a Department Store Telescope then you should FORGET about the "magnify up to XXX times" claimed by the manufacturer. It's meaningless; it's like saying that a Volkswagen Beetle will do 300km/h if you install a Formula 1 speedometer in it. Maybe if you drive the Beetle over a cliff...?

Avoid a telescope that boasts about magnification; look instead for terms like "diffraction-limited" , "coated optics" and allusions to the clarity of the images and the stability of the mounting.
A good telescope has a maximum useable magnification -- under excellent rural skies -- equal to:

The focal length of the telescope may be written on the tube (eg:"F=760mm" or "F=2000mm"); or alternatively the focal ratio (usually written as f/(number) may be recorded. This is related to focal length via the formula:

Eyepieces

• Low power -- about 30x to 50x.
• Medium power -- about 80x to 120x.
• If you can afford it -- and the telescope can handle it -- an eyepiece giving at least 180x. Be warned that this eyepiece will spend many nights in its box, awaiting those rare moments of excellent seeing.

A popular accessory is the Barlow lens, which increases the apparent focal length of the telescope by a fixed ratio (eg: 2 times); thereby increasing the magnification of any eyepiece by the same ratio.
The Barlow goes into the eyepiece holder on the scope, and the eyepiece is then put into the Barlow lens' barrel. You could get by with a single eyepiece and a Barlow if you choose carefully; or use a Barlow to effectively 'double' your choice of magnifications and save buying extra eyepieces.

There are also 50mm (2 inch) eyepiece barrels, originally designed for big telescopes (and with a big price tag). These too are available with a variety of designs and accessories; and an increasing number of smaller telescopes are supplied with eyepiece holders that take both 50mm and 32mm diameter eyepieces.

Eyepiece designs are numerous, and prices vary enormously. Department Store Telescopes invariably come with cheap rubbish designs like Huygenian or Ramsden -- look for H, R or AR codes on the barrels. Kellners (codes K, KE or RKE) are acceptable on telescopes with larger focal ratios (f/8 or higher) or for low magnifications. Orthoscopics (codes O or Or) and Plossls (code Pl) are a good choice for most telescopes. You can also get other excellent -- and expensive -- designs such as Panoptics, Naglers or Pretorias.

Some eyepieces give a very wide apparent field of view, seemingly like looking through a window into space rather than a small hole! This should not be confused with the true field of view which depends on several factors. You need to know the true field of your eyepieces for more effective use of your star charts. One simple way to find the true field is to use the Moon, which is about 1/2 degree in angular diameter. How many "Moon-diameters" can you fit into your eyepiece's view?

What is my scope for?

If you have eyesight problems or a disability, some more advice is available.

Do not attempt any telescope astrophotography or CCD imaging until you have had several hundred hours of observing experience. Taking good pictures through a telescope is not simple, and can get very expensive. Be a visual observer first.

Money - and before you buy

Don't rush into buying a telescope, especially if you fall into any of these categories:

• You have NEVER done any astronomy before.
  
• Your budget is limited -- $300 or less.
  
• Astronomy may be a temporary hobby (for whatever reason).
  

If you're buying for a child then don't be surprised if their astronomical enthusiasm declines or vanishes during adolescence. This is a very common phenomenon :) but in many cases their enthusiasm returns later in life.

Good binoculars for astronomy include 7x50, 10x50 or 12x50 models. Bigger and more expensive binoculars are also sold for astronomy, but you will need to support them on something -- big binoculars are heavy. The numbers on binoculars refer to "magnification x aperture" so 7x50s have a magnification of 7 and an aperture of 50mm. Avoid models with smaller apertures, or which don't have "fully coated optics". There are also some finderscopes (eg: 8x50 or 12x60, as accessories to big telescopes) or spotting scopes which make a good first instrument. If you're buying a spotting scope with tripod for your astronomy, then a model with an angled eyepiece will be more comfortable than a "straight-through" design.

Use your binoculars for several months. THEN go looking for a telescope if you are still keen about astronomy. Your binoculars are not a waste of money -- in fact you will continue to use them for marvellous wide-field views of the sky, for looking at any bright comets, and for taking on holidays, to the beach, to the cricket....

My first purchase was 7x50 binoculars in 1972 and I was still using them frequently until I dropped them onto concrete in late 2000... I might mention that these binoculars were among the first instruments on Earth to detect Comet SOHO (C/1998 J1). For further details, read my reports in the International Comet Quarterly.

If you lose interest in astronomy at this stage, note that binoculars are easier to sell than a telescope. However I'm going to assume that you stayed interested and still want a telescope. The "delay" doesn't really matter. In the long term, the true purchase price for any good telescope model will fall. Or if it stays fixed, then next year's telescope will have more features or better accessories than this year's. Rather like computers....

So your next question is "how much money can I spend?" Be realistic; a fabulous telescope will be no fun if you go deeply into debt.

In general; refractors become very expensive above 100mm aperture, while reflectors are considerably cheaper. This is why bigger telescopes are usually all reflectors. And you guessed it, the bigger the aperture, the bigger the price - and the relationship is very non-linear!

In Australia, expect to spend at least $300 on a telescope, even if you build it yourself. Any telescope retailing for under $300 is junk, and a lot of $300-$500 telescopes are also junk. As I said earlier, if your dollars are limited, get binoculars. $300 is unlikely to get you a decent telescope; but it will almost certainly buy you a good pair of binoculars and a useful star atlas.

Australian retail prices can fluctuate rapidly according to the value of the Aussie dollar, the manufacturing cost of the telescope, and the greed of the manufacturer, distributor and retailer. The prices in overseas magazines may look good; but don't forget the freight costs, Australian import duty and GST, and the problems you may have with your warranty.

Australian price ranges (GST inclusive) for typical models in late 2001 were:

A telescope on an equatorial mounting will cost $100 to $1000 more. And for go-to computer control, add lots more money. Even a small go-to telescope will cost you at least $800.

Many of the cheaper go-to telescopes don't understand Australian time zones (that stupid +9h30m in SA and NT is particularly problematic); although this can be worked around...usually by lying about your longitude or your local time. But some cheap go-to controllers don't even know there's a southern hemisphere - so the telescope runs as though it is on the equator.

You can expect one or two eyepieces to be included in the price of a telescope -- but not necessarily the best ones. Some manufacturers may offer more (or better) eyepieces and accessories; have better after-sales service, include "free" starcharts, etc. And just like cars, you can get expensive "prestige" telescopes which are as much for show as for use!

If you choose to save money by building your own scope, then you can start anywhere from some slabs of glass plus grinding grit, right up to finished mirrors plus fittings that you assemble. The cost of finished mirrors has fallen substantially in recent years, so if you don't feel confident of making your own then buy them.

Good books on telescope making include Howard's Standard Handbook for Telescope Making, Jean Texereau's classic How to Make a Telescope (translated from "La construction du telescope d'amateur") and Richard Berry's Build your own telescope. The two latter titles are available from Willmann-Bell.

If you are buying a scope from a magazine advertisement, read the fine print! A common trick is to show a picture of the fully-featured model, and print the price for the no-features model. This is not illegal, because if you look carefully you may see a tiny note such as " Shown with optional High-Z Quasar Locator and optional Ultra GigaStar9000 Controller." But seriously -- be careful.

Another problem is that many overseas companies offer no warranty protection to "foreign buyers". Some dealers take advantage of this fact to sell off their inferior stock. It has happened before and your Consumer Affairs office are powerless to stop it happening again (they have no jurisdiction outside Australia). Again, carefully read the fine print.

Australian dealers

• You are protected by the Federal Trade Practices Act and other legislation; even in the absence of a specific warranty.
  
• You can pay in $Aust or with a cheque in $Aust. Most places also accept local credit cards.
  
• Items requiring mains electricity will be supplied with the necessary plugs, adaptors or transformers to run from Australian 240V 50Hz power sockets.
  

• Adelaide Optical Centre
  120 Grenfell St, Adelaide SA 5000
  phone 08 8232 1050
  Binoculars, telescopes and accessories. Official dealers for many brands of binoculars; and Celestron , Meade , Optex, Parks, Questar, Tasco & Vixen telescopes.

• Advanced Telescope Supplies
  PO Box 447, Engadine NSW 2233
  phone/fax 02 9541 1676
  Distributors for various CCD cameras, Losmandy mounts, Celestron and Meade telescopes, and Sirius fibreglass observatories.

• Astro Optical Supplies
  9 Clarke St, Crows Nest NSW
  phone 02 9436 4360
  Branches in Melbourne and Sydney.
  Telescope kits and components, locally made reflectors, binoculars, and dealers for Celestron, Vixen, Meade and Zeiss telescopes.

• Astronomy and Electronics Centre
  PO Box 45, Cleve SA 5640
  phone/fax 08 8628 2435
  Dealers and agents for several telescope manufacturers including some highly regarded European and Japanese companies.

• Astronomy Online
  
  phone 02 9401 5620 (or for callers outside Sydney 1300 65 44 11)
  Sales of new and used astronomy equipment online.

• Astronomy Visuals
  147 Kensington Rd, Kensington SA 5068
  phone/fax 08 8364 0328
  Astronomy posters, postcards, slides and videos.

• Binocular and Telescope Service Centre
  2nd level, 119 Burgundy St, Heidelberg VIC 3084
  phone/fax 03 9459 5033
  Binocular, telescope & microscope sales and repairs, accessories, books and secondhand instruments. Parts can also be fabricated if no longer available. Agents for AstroSystems, Rigel Systems, Starlight Express (CCD cameras), Scanner Optics, Questar, Sirius Optics (filters), Pegasus Optics, Guan Sheng Optical, Kendrick dew remover systems; and the publishers Willmann-Bell, Harper-Collins, Quasar, and John Wiley.

• Binocular and Telescope Shop ("Bintel")
  55 York St, Sydney NSW 2000
  phone 02 9262 1344
  Large selection of astronomy books, software, binoculars and telescopes. Official dealers for Celestron , Meade, TeleVue, Mizar, Vixen, Orion, Tectron telescopes and accessories, Lumicon and Novak Research accessories, Thousand Oaks (solar filters), JMI products.

• Camera House
  2 Villiers Place, Dee Why, NSW 2099
  phone 02 9971 3122
  Many dealers throughout Australia.
  Binoculars, and smaller Meade telescopes.

• Clark Astronomical Supplies
  4 Bishops Close, Quinns Rocks WA 6030
  phone 08 9305 2623
  Agent for Parks and Astro-Physics telescopes.

• Deep Sky Optics
  PO Box 188, Berowra NSW 2081
  phone/fax 02 9456 2215
  Custom-made optical components, design and testing. Manufacture and refiguring of telescope optics.

• Deep Sky Telescopes and Binoculars
  Shop 5 row D, The Homemaker Centre, Bunbury WA
  phone 08 9720 1215
  Dealers for Celestron, Optex, Tasco and Vixen. Agents for Sirius Observatories.

• Gecko Optical Classifieds
  Online classified ads for optical equipment.

• Quornucopia
  17 Railway Tce, Quorn SA 5433
  phone 08 8648 6282
  Many types of astronomical binoculars, including giant models.

• Sirius Observatories
  33 Filmer St, Clontarf QLD 4019
  phone 07 3284 2111
  Manufacturers of fibreglass observatories, including custom-built models.

• Starchair
  1 First St, Gawler SA 5118
  phone 08 8522 7272
  Manufacturers of the famous Star Chair.

• Starfield Scientific & Photographic Services
  PO Box 232, Port Kembla NSW 2505
  phone 0425 235 804
  Australian distributors for Rainbow Symphony eclipse glasses and related products.

• Stargate Telescope Supplies
  PO Box 2045, Gateshead Mail Centre NSW 2290
  phone 02 4943 8580
  Dealers for Vixen, Konus, Orion, Intes, Edmund Scientific, Lumicon, JMI, Galaxy Optics, Nova Optical, Unitron and many others. Catalogue available.

• York Optical
  256 Flinders St, Melbourne VIC 3000
  phone 03 9654 3938
  Branches in Brisbane, Melbourne, Sydney and Perth.
  Official dealers and distributors for Celestron and Televue telescopes and accessories. York also sell their own "SkyRover" telescopes, binoculars, telescope kits, telescope parts and accessories; including SBIG CCD cameras, Sirius observatory domes and Kendrick dew remover systems.

Don't buy the ultimate scope yet

Avoid having lots of clever gadgets, because the best telescope is one that is uncomplicated and easy for you to use. As a beginner you will have enough to do without wondering which of 237 controls to use next. Fortunately some manufacturers are now selling computer-controlled telescopes which can be used by beginners; but they come with a big price tag.

A 100 to 200mm aperture telescope is a good starting size for several reasons:

• it will fit into the average car (if you observe away from home) and go easily through doorways (when you bring it home),

• you can carry it unaided,

• you don't need a ladder to reach the eyepiece (unless you're short),

• it will show quite a lot (although not as good as pictures in typical astronomy books),

• ...and, after its purchase, you can probably still afford to buy food ;-)

Things you will NEVER see through your Earth-bound telescope include:

• Spacecraft or other artefacts on the Moon (or any planet). The Moon is about the same diameter as Australia - and the Apollo Lunar Modules are about the same diameter as a Hills Hoist!

• Gorgeous multicoloured nebulae like the pictures in books. Sorry, the human eye loses its colour vision at low light levels. The best the eye can do is faint pastel colours - if the object is bright enough and the telescope is big enough.

• Planetary detail comparable to spacecraft pictures. Why do you think they had to send a camera there to see those things, if it was possible to see that well from the ground? Moreover, most published pictures by spacecraft have been computer enhanced.

• Stars as discs. If you do, it means your telescope isn't focused properly for your eye - stars should appear as points of light (enclosed in diffraction phenomena on good nights).

Computer control pitfalls

If you do buy a computer-controlled telescope -- or even one with a simple tracking motor -- make sure that it works correctly for the Southern Hemisphere.

Our sky spins clockwise -- the opposite direction to the Northern Hemisphere. And no, you can't fix it simply by reversing the battery connections; doing this is likely to destroy the electronics and your warranty! You need a reversing switch (a.k.a. hemisphere switch or N-S switch), or a permanently rewired motor.

On a related issue, if you live in SA or NT check that your computer controller (or astronomical software) accepts Australian Central Standard Time. Some products just can't understand that stupid half hour...!

Another problem with the cheaper equatorial telescopes: the supplied RA setting circle index scale (from 0h to "24h") is usually "backwards" for Southern Hemisphere users, as shown in this diagram. You can make your own index by attaching a strip of paper, with the correct labels, over the existing index scale. Better equatorials will have two index scales -- and instructions on which one to use in each hemisphere.

Sun filters

Your telescope may come with various gadgets and accessories but one accessory to avoid is the so-called "Sun Filter" designed to be screwed into an eyepiece for viewing the Sun directly. Eyepiece sun filters are extremely dangerous to use and have been banned from sale in Australia. If you still have one, destroy it. With a big hammer.

Why? Because a telescope collects far more sunlight -- and heat -- than your eye; and will cause enormous thermal stresses in an eyepiece filter. Furthermore, your eyeball contains no pain nerves; which means that you cannot rely on your pain-avoiding reflexes to save you if the eyepiece filter fails. Therefore if the eyepiece filter cracks while you're looking at the Sun, you WILL get permanent and irreparable eye damage. 7x50 binoculars can be used to burn holes in wood. A 100mm telescope can melt holes in aluminium!

There are only two safe ways to telescopically view the Sun.

1. You can project its image from the eyepiece out onto a white surface (eg: paper), and view this projection. Projection Screens are commercially available for most species of telescope, but making your own is easy. Do NOT look through the eyepiece or finder scope while aiming the telescope at the Sun! Look at the shadow cast by the telescope tube -- when it's smallest, you're aimed at the Sun. Also, reduce the aperture of your telescope to about 50mm by using a cover with a hole in it. This will reduce the thermal stress on your optics.

2. You can use a FULL APERTURE Solar Filter fitted over the FRONT of the telescope, which will pass less than 1/100000 of the Sun's light -- and none of its dangerous UV or infrared radiations -- into the telescope. You need a genuine Solar Filter such as those made by Baader, Tuthill, Thousand Oaks or Lumicon.

   Cheap substitutes such as dark or coloured or sooty glass, overexposed photographic film, Polaroid plastic, "crossed" Polaroids, oxyacetylene welding goggles, conventional sunglasses, wine cooler bags, ordinary aluminised plastic sheets, aluminised food wrappers, Compact Discs (CD/DVD), black plastic sheets, or conveniently-placed clouds ARE NOT SAFE! These products may block a lot of visible light BUT they STILL allow dangerous amounts of UV or infrared to reach your eye.

Several manufacturers sell eclipse sunglasses. Their lenses are made from a high-quality aluminised plastic and are capable of protecting your eyes during direct naked-eye viewing of the Sun. They are NOT designed to protect your eyes if you look through unfiltered binoculars or telescopes. The intense heat coming from the eyepiece may destroy them.

Star atlases

Knowing your sky will make it MUCH easier to find things with your telescope (and to impress people with your knowledge). Even if you have a "fully computer-controlled" telescope, you will be able to initialize it much quicker. And you will be prepared for the inevitable night when your telescope's batteries go flat.

The all-sky charts in the astronomy magazines will help you begin. Sky & Space, Sky & Telescope and Astronomy have charts each month; and you should soon learn where the principal constellations and brighter stars are. These magazines also describe the current locations of the planets.

There is no need to learn every star or all 88 constellations. I never bothered -- that's why I have star atlases -- and, frankly, most official depictions of constellations can't be deciphered without the help of alcohol ;-)

Printed star atlases

When you become experienced with your sky, the Sky Atlas 2000 or Uranometria 2000 are good atlases for finding fainter objects. Sky Atlas shows everything visible to 7x50 binoculars (~43000 objects), Uranometria goes even fainter. And for even greater detail in printed star maps, try the Herald-Bobroff AstroAtlas or Sky Publishing's Millennium Star Atlas. Both of these depict over one million objects.

Star atlas programs

Many astronomy programs are available as freeware or shareware from Australian mirrors of popular archives such as SimTel. Look in the "astronomy" sub-directories under your operating system's directory.

Again, if you live in SA or NT check that your chosen astronomical software accepts Australian Central Standard Time. One good planetarium program for beginners is KlassM Software's SkyGlobe 3.6, which runs on any DOS or Windows system capable of displaying graphics. It also runs in the Linux DOS emulators, and I'm told it also works in the MacOS DOS/Windows emulators. You can download a copy here. (350kB)

More advanced programs generally run from a CD-ROM, and many can interface with professional-level data sources. Guide, for example, comes in DOS and Windows 3.x/95 versions and all can display over 20 million objects from the databases on the CD-ROM. All Guides can also use data from the RealSky CD-ROMs, the Digitized Sky Survey, and the 520 million objects in the USNO A1.0 or A2.0 Catalogues. The asteroid and comet databases can also be updated from online sources such as the Central Bureau for Astronomical Telegrams. And it can be used to control some telescopes.

If you live in the Southern Hemisphere and you're about to buy a book that doesn't discuss the Southern Cross (a.k.a. Crux), Carina, or how to find south -- put it down and keep looking. One of the classic beginner's books for Southern Hemisphere readers is The Southern Sky by Reidy and Wallace. Norton's Star Atlas and Reference Handbook -- the latest edition is called Norton's 2000.0 -- also contains much useful information for observers everywhere. And (fortunately) there are now an increasing number of observing guides which cover both hemispheres.

There is a difference between "books about astronomy" and "observing guides". The books will tell you a lot about What Is Out There and How Things Were Discovered; but the observing guides actually tell you where to find specific things and what you can expect to see in your instrument. Note, however, that most observing guides are designed to be used in conjunction with a good star atlas. The classic observer's guide for the Southern Hemisphere is Hartung's Astronomical Objects for Southern Telescopes (recently updated by Malin and Frew). The 3-volume Burnham's Celestial Handbook is another classic, covering both hemispheres; but its coverage of very southern objects is patchy. Harrington's Touring the Universe through Binoculars is an ideal guide for binocular users.

Astronomers have been compiling catalogues for centuries. Among the most famous is the Messier Catalogue, prepared by the French comet-hunter Charles Messier (and friends) in the 18th century, all using small telescopes in Europe. This catalogue -- the first list of what are now called "deep-sky objects" -- was originally intended as an aid to comet-hunters. Many comets look like fuzzy blobs in a small telescope. Many star clusters, nebulae and galaxies also look like fuzzy blobs; so comet-hunters (then and now) have to know which is which.

The Messier Catalogue is listed in many books but it ignores much of the southern sky. Hardly surprising because the compilers couldn't see that far south! The Bennett Catalogue -- also compiled by a comet-hunter (in the 20th century) -- is a Southern Hemisphere version; and the Caldwell Catalogue is a whole-sky version. All three catalogues contain many deep-sky objects suitable for small telescopes.

The Caldwell Catalogue originally appeared in an issue of Sky &Telescope, and Sky Publishing now offers both a printed and an online version. The Bennett Catalogue is available online from the Astronomical Society of South Africa's Deep-sky Observer's Companion. This excellent site also contains many descriptions of southern nebulae, galaxies, and clusters, as seen through a variety of telescopes. It also has a good online description of Southern Hemisphere Polar Alignment.

• Sky & Telescope's Backyard Astronomy pages.

• The Weatherman.

• StarCruiser

• Making your own telescope
• The Telescope Reviews site

Some Australian astronomical society webpages:

• NSW and ACT
  • Astronomical Society of New South Wales
    
  • Canberra Astronomical Society (ACT)
    
  • Newcastle Astronomical Society
    
  • Taree Astronomical Society
    
  • Sutherland Astronomical Society
    
  • Western Sydney Amateur Astronomy Group
    
  • Wollongong Amateur Astronomy Club
    
• NT
  • Astronomical Society of Alice Springs
    
• QLD
  • Brisbane Astronomical Society
    
  • Southern Astronomical Society
    
  • South-East Queensland Astronomical Society
    
• SA
  • Astronomical Society of South Australia and its Whyalla branch.
    
• TAS
  • Astronomical Society of Tasmania
    
• VIC
  • Astronomical Society of Frankston
    
  • Astronomical Society of Victoria
    
  • Bendigo District Astronomical Society
    
• WA
  • Astronomical Society of Western Australia
    
• New Zealand also has several astronomical societies on the Internet. The RASNZ homepage is an excellent gateway to all NZ astronomical resources.
  

Something to ponder on those cloudy nights....

And some dimwits think astronomy and space exploration are a waste of money....