So You Want to Buy a Telescope

It’s that time of year again: when a lot of folks try for the first time to wade into the murky waters of buying a telescope, usually as a holiday gift for a budding astronomy enthusiast in their lives. There’s a lot to consider, and a lot of terms that are unfamiliar to anyone not used to messing around with astronomical instruments. 

I’ve gotten many inquiries over the years from folks looking for a little help buying a telescope, so here’s what I usually tell folks. This is really going to be for first-timers—if you’re an experienced telescope owner and operator I doubt you need help from the likes of me.

Resist Temptation

Someone in your life is getting really into astronomy! Huzzah! Maybe it’s a kid, maybe an adult (maybe it’s yourself!), and you really want to support their astro enthusiasm by getting them a telescope. And to show how much this person means to you, you want to get them a really nice telescope.

Resist it. It’s a lovely sentiment, but it’s also a trap. Very nice telescopes can be quite expensive, and they also tend to be complex to operate and often are very heavy. You know a great way to kill someone’s burgeoning love for astronomy good and quick, especially if it’s a kid? Get them a telescope that’s hard to move and a pain to learn how to operate. 

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The best telescope to get someone is the telescope that they are going to use. This may actually be something on the simpler, less expensive end of the spectrum, something relatively easy to use and quick to set up. And in fact the best telescope to get a first-timer may not actually be a telescope at all.

Consider Binoculars

Boy, the dumbstruck silence I get when folks ask me what telescope they should buy and I tell them it’s a pair of binoculars. Honestly I get a little bit of a kick out of it. It’s a character flaw, but one I’ve decided I can live with.

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Binoculars have a lot going for them as a first astronomical instrument. They’re portable, even the bigger ones. It’s a good idea to have a tripod when using binoculars to look at the night sky (human hands are shaky), which will need to be purchased separately, but attaching binoculars to a tripod takes very little time which means they’re easy to set up. And a good pair of binoculars will show you many wonders in the sky, from planets to the details of the lunar surface to the brighter deep sky objects. 

I have a confession. I have a telescope, and it sits in my closet largely untouched. I also own a pair of binoculars and those I pull out frequently. I have enjoyed beautiful views of the Andromeda Galaxy through those bad boys while still well within Boston’s horrible light pollution, I’ve tracked the moons of Jupiter through them, and one of my fondest memories from the dark days of 2020 was tossing my binoculars in my car, driving to a nice dark site, and setting them up to study the comet C/2020 F3 NEOWISE as it brightened in the Northern Hemisphere. I love my binoculars.

How to Pick Out Binoculars

The pair I own is 15x70. This is how binoculars are identified. The first number tells you what the pair’s magnification power is, while the second tells you the size of the front lens (the important one) in millimeters. Most folks, hearing this, would assume that you want that first number to be nice and big, but that’s not necessarily the case. You can do some perfectly good observing if that first number is in the 7-8 range, though I wouldn’t go lower (for astronomy anyways).

The second number is where a lot of the binoculars’ abilities will come from. It tells you how big the light-collecting surface is (the official term for this is aperture—it’s going to come up again), and that’s a huge factor. I went big with mine—70 sweet millimeters of light collecting surface. That has a drawback though—these binoculars are almost a foot long and they have some weight to them. If your intended recipient is a kid, binoculars this size might be difficult to handle.

And you don’t need binoculars that big—I just chose to indulge myself. Basically, look for that first number to be at least a 7 at minimum, and for the second one to be, say, 40 or higher. And the best part is that you can get a great pair of binoculars without breaking the bank. And then you can use them for birdwatching on the side.

But I Really Want a Telescope 

Okay, so what you seriously want to get is a telescope. That’s fine! There is something undeniably appealing about a telescope. In which case it’s important to keep that primary principle in mind: the best telescope is the one that will be used. In my experience, a big thing to consider is the weight. 

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I know, we need to consider how powerful the telescope is as well. Aperture is important. The larger the aperture, the more sensitive the telescope. That light-collecting surface can be a lens (in which case the telescope is called a refractor) or a mirror (a reflector). So…bigger is better, right?

Bigger is absolutely more powerful. That doesn’t necessarily make it better, in this case, because bigger means heavier (not to mention more expensive). A larger aperture is a big factor in driving up the weight of a telescope. I looked up the specs on an 8-inch reflector from a leading telescope company. The telescope itself weighed 33 pounds and the tripod was another 19. It also cost well over $2,000, which is not odd for a ‘scope of that size with bells and whistles.

The views through such an instrument would be incredible, but taking it out would be an undertaking. Imagine a kid trying to move something of that weight. If the sky-watcher in your life is at the beginning of their astronomical journey, having to haul something like this out could be a major deterrent in deciding whether or not to go observing. 

And if their goal is to enjoy the night sky and get good at identifying its wonders, you don’t need something that big! My first telescope was a 3-inch refractor. It was easy enough for me to carry that I could just set it up anywhere anytime the fancy struck me, and I enjoyed some great nights with it (and obviously never lost my love for astronomy). For a first telescope, my recommendation is to not go below 3 inches in aperture. You can go up as high as you want (and are willing to pay for—price jumps pretty quickly with aperture) but keep an eye on the weight. 

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A lot of telescopes come with motorized mounts. These are great because they’ll move the telescope as the sky moves with time, making sure your sky targets stay in the field of view. These days they also often come with computers in them that will point the telescope for you—if you align them properly using guide stars.

This is where the ease-of-use thing can come in. These systems can be annoying and have to be re-aligned anytime the telescope is deployed. That doesn’t necessarily have to be a deterrent, especially since you can usually still point these telescopes by hand if you want. I personally think pointing by hand means that an astronomer learns the night sky better, but I’m not going to stand too high on that soapbox—aligning your telescope’s computer will also require you to learn the sky.

Other Factors 

Refractor vs. reflector? There are those with hardcore opinions about this. I’m not one of them. Reflectors can be made with much bigger apertures than refractors, so probably anything above a 4-inch will be a reflector, but either and each can give you a great view of the sky. If you’re looking at a refractor, you’ll want to make sure it has an achromatic lens to ensure a clearer image. All else being equal, reflectors will usually cost less for the same aperture because the mirrors are cheaper to produce. But then it’s hard to find a case where all else is equal. 

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What does the telescope sit on? Usually this will be a tripod, but you can get tabletop models that, as the name implies, just sit on a table. Tabletops generally will not have any electronics in them, but it doesn’t get much easier to deploy than this sort of telescope—just plop it down and point it.

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There’s also the Dobsonian model. These can be quite large, but they sit in a relatively simple Y-shaped bracket on a spinning base that sits on the ground. A Dobsonian is a relatively cost-effective way to get a large aperture telescope, since it has absolutely no bells or whistles (no electronics). It’s just a light bucket. It can be an amazing tool for a new astronomer but they can get quite heavy, so watch it. 

Look Up!

If you take nothing else from all this, remember that a first astronomical instrument doesn’t need to be anything huge or fancy. There’s plenty of wonderful things to observe through smaller, lighter, less expensive tools. And while encouraging a burgeoning interest in astronomy is a wonderful thing, the interest doesn’t always last, and then if you’ve shelled out for a big, expensive telescope you now have a big, expensive object gathering dust in the corner of the coat closet.

If the sky-watcher in your life is still into learning about the night sky and regularly using their binoculars/small telescope/whatever in a year or two, then maybe you can think about making a more serious investment in a bigger, fancier telescope. In the meantime, anything that encourages a new astro enthusiast to keep looking up will be just the thing they need. Happy sky-gazing!