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What's a good telescope for my 6 year old? We're both brand new to telescopes in general, but love space, stars, planets, cosmology, etc. Happy to spend up to $200 to start. Maybe more for a good reason...

UPDATE: Thank you guys for all the really great answers. I'm about to purchase the Celestron AstroMaster 114 EQ. Seems like the best value for the money based on the feedback below.

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5 Answers 5

Telescopes (and binoculars) are, primarily, light-concentrating devices. I get the impression that most people unfamiliar with telescopes think of a telescope as a "microscope pointing upwards". It is no such thing; a microscope's purpose is to magnify the image of a small object, and it uses a "strong" backlight for illuminating the object under the eyepiece. On the other hand, a telescope "funnels" the available light from the object itself (which might be feeble); the amplification of the image comes second, in that respect, so if you amplify an image you're spreading the same light over a wider area. Remember that when buying a telescope from a vendor claiming "large magnifications" (read: "unreasonable expectations").

With that idea of telescope/binoculars as light-funneling-devices in mind, the very first thing I'd suggest (since you're starting out) is that you buy binoculars instead of a telescope. The usually recommended binoculars are 7x50, 8x50 or 10x50 (to the left of the x is the magnification, to the right of the x is the diameter (in milimeters) of the objective, where light goes in). Anything smaller doesn't capture that much light; anything bigger than that becomes too heavy and unwieldy, both for you and for your kid. Since he's still young I'd recommend a lighter 7x50 which is still quite good.

There are several reasons for picking binoculars instead of a telescope.

  1. They're comparatively less expensive. This is a plus, especially if you remember that most first-time telescope buyers spend about 10-15 minutes with them before putting it in the attic for the rest of their lives (or selling on e-Bay).
  2. They're much more portable than a telescope; that's a plus. It can also find application when you go out camping for example, because you can carry it in the back pack to watch animal life.
  3. It's usual for small children to have trouble closing one eye and looking through a telescope's ocular (even though there are attachments which split the light, thus costing more). A binoculars makes it easier for them because they don't have to make extra effort.
  4. Many first-timers become confused when they pick a telescope because the image on the ocular is inverted; they push the telescope to the right hoping to see something "on the right" and instead the image goes left, they push the telescope up and the image "goes down". There is no such problem with binoculars since it has image-correcting prisms (it takes up a substancial amount of the binoculars' weight).
  5. When you don't know the night sky (constellations, etc), finding something on the sky without knowing your way arround is a good and fast way to frustration (and throwing the telescope into the attic). If you buy the binoculars and a good guide, it'll be better than spending your budget on the telescope (and no guide).

However, if you insist on buying a telescope, I suggest that you start out with something relatively inexpensive. There are two instruments that I can suggest for a small child.

  1. Celestron FirstScope.
  2. Orion FunScope.

I'm suggesting these because they're "tabletop" telescopes, meaning you just have to put them on a flat, level surface: it comes with its own "mount" so that you don't have to spend more money buying an equatorial mount (although there's nothing wrong with that and it's perfectly possible).

You can consider buying a larger telescope when both you and your child find out you want to take this hobby more seriously. These two are also relatively inexpensive and easily manageable. They'll allow you to view the larger features on the Moon, identify satellites around Jupiter, identify Saturn's ring. You won't see much details though, but it's still good for starting up.

If you spend a few good nights with that, you'll gradually want to progress further -- either choosing a telescope or a binoculars. But those are a good compromise between not being sure if you want to take it past one or two tries, or getting used to "what it feels like" before going for something more ambitious.

In any case, I also recommend two more things.

  1. Get a good sky guide. Example: Turn Left At Orion.
  2. Look for local astronomy clubs. This is very important if you want to develop your skills and learn. The other members have gone through what you've gone through and will be patient in teaching you and letting you pass the first hurdles.

One final important advice. I don't presume you'd overlook this, but never point and look with a telescope (or binoculars) at the Sun. (Hint: Have you ever burnt ants with a magnifying glass? That's what I'm talking about.) If you're observing at night you should be safe about this (for obvious reasons) but during the daylight you'll have to watch your boy so that he doesn't accidentally look to the Sun (e.g. when spotting an animal on a tree).

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This is excellent advice! There is so much to be learned and seen with a good pair of binoculars. And I mean good. Spend a couple of hundred dollars on high-quality binoculars. If you have the money, the Canon image-stabilized ones are absolutely wonderful! The 8x25 IS can be had for under $300 with careful shopping at the photo discount houses. –  Bob Denny Sep 30 '11 at 15:49
    
I fixed the left and right issue. PS, for a second mount, get a GOTO mount. For someone new to visual observation, it is a much more fulfilling experience being able to see a dozen or two things in one night than having to hunt all over the sky and not being sure you're actually seeing what you're supposed to be seeing. –  Andrew Sep 30 '11 at 19:25
    
@Joe Thanks for noting. –  jbatista Sep 30 '11 at 20:24
    
@Andrew Thank you for fixing. –  jbatista Sep 30 '11 at 20:24

The answer jbatista provided is good, if on the conservative side. "Turn Left At Orion" is an excellent recommendation. Install Stellarium on a laptop or iPhone. Get the Pocket Sky Atlas for a dead-tree format of the map.

Here's a different view, aiming to shoot a bit higher:

If you do get binocs, do not forget that you never do astronomy hand-held. The binocs must be sitting on a tripod.

But for the price of binoculars, you could get the Galileoscope instead:

https://www.galileoscope.org/gs/

The objective lens is a surprisingly good achromat doublet. The instrument accepts standard 1.25" eyepieces. Plus, the 6 year old and the dad have the opportunity to build the scope together and, therefore, learn how it's made. You will need a photographic tripod to keep the instrument in a fixed position while observing, see if you can find a non-wobbly one for cheap at a garage sale (it's important that it doesn't wobble).

I'm not a big fan of the numerous "starter scopes" or "first scopes". While cheap, they are often poor quality. The beginner has no chance of choosing correctly between the good and the bad ones. That leaves a big hole in the \$100 - \$300 interval. Below that, there's binocs and the Galileoscope. Inside that interval, there's a whole lot of hot air and deceptive marketing.

Here's a possible exception - the Orion SpaceProbe 3 Altazimuth:

http://www.telescope.com/Telescopes/Beginner-Telescopes/Orion-SpaceProbe-3-Altazimuth-Reflector-Telescope/pc/-1/c/1/sc/21/p/9883.uts

I say "possible" because I haven't looked through it. But it seems promising because it has a long focal ratio: it's an f/9 scope. It's hard to screw up such a long focal ratio. You could plop in a cheap eyepiece and chances are it will work okay.

The other "beginner scopes" are very short, very fast focal ratios, f/4 or even shorter. It's hard to make such fast optics, or if you do make them well they're not cheap. My feeling is that those scopes are rushed out jobs, because of the low price. But even if they are made at a high spec, at f/4 focal ratio few eyepieces will work well; all the cheap eyepieces will be under huge pressure to perform, and will fail, no doubt - the image will be full of aberrations. Only very high-end eyepieces (that cost several times more than the whole scope) will perform well and will not add to the already existing problems of the cheap fast mirror.

So, if you do get a "beginner" scope, look for the ones with a long focal ratio, like f/8 or maybe even higher. They are far more forgiving on the eyepiece, and are far easier to make to a higher standard. They are not guaranteed to be better, but chances are higher in that region.

Finally, if you feel this will be a long time hobby, there is a scope that could possibly last you a lifetime (unless you're bitten by the aperture fever bug) - the 8" dobsonian:

http://www.telescope.com/Telescopes/Dobsonian-Telescopes/Classic-Dobsonians/Orion-SkyQuest-XT8-Classic-Dobsonian-Telescope/pc/1/c/12/sc/13/p/8943.uts?refineByCategoryId=13

It's above your stated price limit, but you said it's okay if it's for a good reason. Well, this is a scope that will show you a lot, for many years to come. The 6 year old will need a stool to stand on, when looking at objects overhead, but otherwise there should be no problem. It's much bigger than the beginner scopes, so think about it, and decide whether this is okay at this point or not.


Some more advice:

Magnification means nothing. Don't get fixated on huge magnifications. Even if your car can do 300 km/h, you don't drive all the time pedal-to-the-metal. You go slowly to the grocery store. You go faster on the highway. You go very slowly when parking the car. Different speeds for different needs. Same with scopes and magnification.

The atmosphere will limit your instrument anyway. At 150x magnification, not much of a limit. At 250x things get sketchy. At 400x you need really good skies, or else the image will look like a pile of wobbling jello. This is called "seeing", and it affects all instruments.

You change magnification by changing the eyepiece. If F = focal length of the primary mirror or lens, and f = focal length of the eyepiece, then:

Magnification = F / f

Ideally, you'd need several eyepieces to cover a wide range of mags. This is much less of an issue with small scopes; two eyepieces will suffice. With larger instruments, eventually you may feel the need to build up a collection.

What does matter is aperture (the diameter of the primary lens or mirror). That is the main limiting factor of a scope. A bigger aperture will always show you more. But at the same time it's more expensive and harder to wield.

With a small aperture, high magnifications are pointless - the image looks like a 50 x 50 pixel photo that was blown up a lot in Photoshop. With a beginner scope, it's usually pointless to go above 100x or so. Larger apertures allow higher magnification, but then seeing may or may not limit you, depending on current weather conditions. A huge dobsonian may allow 1000x mags, but then you need once-in-a-decade seeing conditions in a very good location; most of the time, under normal seeing conditions, it will chug along at 1/3 of that.

As a general, not very strict, rule, the maximum useful magnification is twice the aperture measured in mm. The Galileoscope has 50 mm (2 inches) of aperture, so the max useful magnification is around 100x. A 4 inch (100 mm) scope goes up to 200x. The 8 inch dob goes to 400x. But all this depends on seeing and a whole lot of other factors.

You will spend a lot of time at low magnifications, too. E.g., when observing large objects that you want to grasp at once. So don't forget about the low end, it's important.

Aperture also affects the brightness of the image. Small aperture will not be able to show you the very faint objects. Large aperture captures more light and you see distant galaxies and quasars and whatnot.

Light pollution might be an issue. It's not a problem for bright objects like planets and double stars, but it is a problem for nebulae and galaxies. Dark country-side skies are much better than the washed-out urban ones.

Clear skies to you!

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+1 on the additional recommendations and the advice re. magnification. –  jbatista Sep 30 '11 at 20:35

I've had a lot of experience with small kids at star parties and, to be honest, I have to say that a 6-year-old, no matter how mature or enthusiastic, is probably too young to use a telescope. I'd recommend binoculars instead, and holding off on a telescope for another couple of years. I've just found that 6-year-olds lack the physical coordination to place their eye at an eyepiece. Trying to look through a telescope when they can't see anything is enormously frustrating for them. If it's any consolation, many adults nowadays have trouble looking through a telescope: all their life experience leads them to look at, rather than through things.

Instead, get a small light-weight binocular, 6x30 or 7x35, which will act as "training wheels" for the eyes.

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Thanks for adding this answer. This aspect was completely forgotten in all the other answers. (+1) –  xmjx Oct 7 '11 at 6:29

You are between a rock and a hard place (or how is that saying?).

On the one hand you want a decent telescope. If you buy a cheap one you minimize the money-related risk but increase the risk of not liking your new telescope. Bad telescopes are difficult to use which makes the whole experience much less worthwhile. If you buy a great telescope you shift the risk from having difficulties towards the money-related risk.

You could do two things:

The first one is spending some nights outside with your kid and getting oriented in the sky. Find constellations, try to name stars and meet Jupiter, the oh so shiny buddy who will be your company in the following time. You won't have to buy a telescope for this and you will have it much easier to find stuff you are interested in afterwards. Also, you will find out if freezing to death is really your thing. ;-)

If you have some degree of orientation you might want to get a binocular. Even if you later buy a huge telescope you will always want to have a binocular because there are plenty of things that can better be observed using a bino than using a telescope (e.g. comets and open star clusters). Since you really want to keep this bino buy a good one.

The other thing is to go to a star party. Amateur astronomers meet from time to time (usually a weekend around new moon because the sky is darker, then), share infrastructure, have a chat and show off their telescopes. This is an awesome opportunity to see different types of telescopes and try them.

Nice telescopes for visual observation are dobsonians. They are set up in 2 minutes (no kidding) and have a great aperture-per-money ratio. Also you can operate them without needing electrical power and transporting them by car is relatively hassle free.

Buying a Goto mount isn't the best idea because the cheap ones will only allow you to find stuff. That's about as much fun as playing paper chase and somebody tells you where to go. If you want to take photos later you will need a much more expensive one since it will have to be sturdy enough to support your telescope and still move very smoothly so your images will be sharp.

A last hint: there is a German book that deals with all the aspects of buying a telescope. Maybe there is also a book in one of the languages you feel comfortable in. There are many aspects to consider and only few can be discussed in a short internet post.

The German book is "Kauf-Ratgeber Teleskope" by Ronald Stoyan and Bernd Gährken, published by Oculum. http://www.oculum.de/oculum/titel.asp?ID=0110201112001611&Nr=50

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You mention that there is a German book that might help, but you forget to provide the details (author, title, publisher, year). How's that supposed to help anyone who might happen to understand German? Kindly provide more details for the benefit of others. –  jbatista Sep 30 '11 at 21:23
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Just added the reference. Thought nobody would read it anyway ;-) –  xmjx Oct 1 '11 at 10:03
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Thanks for adding the reference. You never know when a German reader happens in on this thread and reads your reply. –  jbatista Oct 1 '11 at 13:22

Golden rule of amateur telescope use: The bigger/heavier it is the less it will get used!

But seriously, avoid the biggest you can afford straight away, a bit more spent on quality of mount and optics will lead to a more impresssive and therefore more fun operation.

Have fun!

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