Discover the best telescopes for stargazing on the market. As Black Friday deals run into the weekend, we're expecting to see the excellent telescope deals continue to run on the best telescopes available right now. As well as picking the very best, we've included telescopes to suit every level of astronomer and covered every budget. There will definitely be something here that's perfect for you.
If you're an avid bargain hunter, check out our telescope deals page, which we regularly update with the best telescope deals as we find them. Deals aside, though, if you're seriously interested in getting the best stargazing experience, this is the guide for you as we've got the best models from top manufacturers, available from reputable retailers.
The best telescopes Black Friday deal available today:
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Celestron NexStar 8SE Telescope:
was $1599, now $1452.11 (opens in new tab)
This scope, 'the world's most beloved telescope', is good value for money, but it sits at the pricey end of the market. It is currently on sale with a $147 discount, so it's a good time to snap it up.
We also have brand-specific guides for Celestron, Skywatcher, Meade, and Orion deals for those that are loyal to their favorite brands. Like this page, we keep those updated year-round, so they're always worth checking out.
Before buying one of the best telescopes on the market, you must consider what you want to achieve with one. For example, if you want to view faint deep-sky objects like nebulas and galaxies, you'll want a reflector telescope. On the other hand, a refractor telescope is better suited for views within our own galaxy such as the moon and other planets.
There is also the catadioptric telescope, which can work as a happy middle ground. Some models have computerized motors that make aligning and tracking targets easy, and can even capture images for you, excellent news for astrophotographers.
For anyone wanted to save some money why not check out our guide to Budget telescopes under $500, or for those new to astronomy our best beginner telescopes and best telescopes for kids guides. A pair of the best binoculars are useful skywatching devices, too and the best cameras or best cameras for astrophotography can capture the night sky excellently.
Gemma is an astronomer who has been observing the night sky for 28 years, using a variety of different telescopes and binoculars from Celestron, Meade, Sky-Watcher and Orion, among others. Her favorite targets are galaxies and nebulas, of which she researched during her undergraduate studies at Cardiff University. She also enjoys observing the planets of the solar system, particularly the rings of Saturn and the moons of Jupiter.
Best telescopes 2022
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After reviewing the Celestron Astro Fi 102 telescope we'd say this is perfect for beginners who don't have prior knowledge of the night sky but want to start learning and enjoying what it offers straight out of the box.
It's not a budget scope by any means, but if you're looking for a telescope that comes from a trusted brand that is highly portable, this one is worth a look.
This is a good grab-and-go option when weighing in at a tiny 6lbs (2.7kg). It doesn't have a huge footprint as some telescopes do, so you can leave it set up at home without compromising your space too much, or it's easy enough to pack away and reassemble at will.
The final finish on the telescope feels a little toyish to the touch, and compromises such as the materials used have been made to keep the scope as lightweight as possible.
Despite the slightly lackluster final finish, the image is attractive, and you can explore the detail on the Moon's surface, Saturn and its rings, Mars and Jupiter. You may also see nebulae and other deep sky objects in the right sky conditions.
It's very quick and easy to sync with Celestron's SkyPortal app, which contains approximately 100k celestial objects to explore.
- Read our Celestron Astro Fi 102 review
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Celestron StarSense Explorer LT 114 can be enjoyed by beginner and intermediate skywatchers alike and will be especially desirable to busy users who lack the time required for lengthy set-up procedures. During our Celestron StarSense Explorer LT114 review we timed assembling this telescope — it took less than 20 minutes!
Celestron's StarSense technology is built into this reflector, which provides an extremely easy way to align the telescope. The skywatcher needs to download the StarSense app from Google or Apple (opens in new tab) and take a smartphone image through the eyepiece, the app then works out which stars are in the telescope's field of view to calculate which way it is facing, clever.
Not only that, but the app also offers interesting information on each of the targets you can observe. It gives you a better understanding of what you're looking at for a more immersive experience.
You can enjoy the gas giant of Jupiter (opens in new tab) by using the 10 mm eyepiece. The views are clear, but you'll need a selection of eyepieces (check out our best eyepiece buying guide) and filters in order to pick out the coloration of the atmospheric bands. The planet's largest moons are visible as clear, sharp points of light. Views of the moon, Venus (opens in new tab) and the Beehive Cluster (Messier 44) are also pleasing and clear.
We found that the StarSense Explorer LT 114 is built sturdily and operates smoothly when slewing from one target to another. The scope needs to be manually operated, so you don't get the ease of tracking that computerized telescopes would offer. However, some skywatchers prefer the hands-on versus electronic approach, and what's more, the price is lower.
Of course, you get the usual high-quality optics that we've come to expect with Celestron telescopes and the aperture is a good size too. All in all, this is an excellent choice for a budget-friendly backyard telescope.
Best telescopes for enthusiasts(opens in new tab)
The optical system of the Celestron NexStar Evolution 9.25 ranks as one of the best we've ever had the pleasure of observing the night sky through. With no interference or optical defects in the field of view, this high-quality instrument offers sights of a wide selection of astronomical targets with impressive clarity and contrast.
Although it is expensive, you get a lot of value for money with this telescope and its setup. The list of accessories you get include: an attachable camera, a red dot finderscope, an international AC adapter, hand control for a seamless AutoAlign process and 13mm and 40mm eyepieces.
The stand-out piece of equipment with the NexStar Evolution 9.25 is undoubtedly its single-fork arm. Observers can slew from one target to the next and continuously onwards at the touch of a button for up to 10 hours of continuous use, thanks to its rechargeable lithium-ion battery.
Built into the mount is the telescope's very own Wi-Fi network, allowing the instrument to connect and control via the Celestron SkyPortal app (downloadable for free on iOS and Android). Being motorized, the mount can track objects as they move across the sky, making the NexStar Evolution 9.25 a must-try for astrophotography.
If you're looking for a complete high-definition tour of the universe, then we fully recommend this GoTo to seasoned skywatchers with decent budgets. The only downside is that the NexStar Evolution 9.25 is tricky to transport due to its weight, meaning that skywatchers will need to consider this before planning any trips beyond the backyard — a small trade-off given the telescope's robust and high-quality design.
If the Celestron NexStar Evolution 9.25 is out of stock in the U.S. Look at the NexStar Evolution 8 as an alternative.
When we reviewed the Celestron Astro Fi 130 telescope we liked it a lot and think it's excellent value for money. While it's not necessarily a budget telescope, it is a lot more affordable than a few of the other telescopes on this page and we think it's excellent value for money.
If you're new to stargazing, or even if you just don't have a lot of experience, this telescope can give you an astronomy experience to marvel at. A 130mm aperture means that plenty of light is able to travel through the lens, making the night sky targets clearly visible. A focal length of 650mm means you'll get a wide field of view, you also get amazing views of stars, and can track targets within our solar system with ease.
This telescope is also sturdy but still lighter than some other scopes you might consider for the same experience, so it scores well on ease of transport. You also get a stable tripod, a red dot finder and decent eyepieces, which makes this even better value for money.
We can only think of two things that let you down a bit with this model: the battery life drains a little quicker than you might want, and the eyepieces aren't the best.
You might want to consider upgrading the eyepieces for a better viewing experience, but for value for money, we highly recommend this scope
- Read our Celestron Astro Fi 130 review
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Though not our favorite, we include this scope here because it is a cost-effective way to skywatch. The telescope comes with a 127mm aperture and is competitively priced, meaning you can view our solar system and deep-sky targets without breaking the bank. It can also be used as a terrestrial telescope, though it won't be for everyone as the optics are pretty basic and limiting.
The Celestron PowerSeeker 127 EQ comes with two eyepieces: 20 mm and 4mm, which work with the optical system to produce magnifications of 50x and 250x. There's also a 3x Barlow lens for tripling the magnification on the eyepieces, though truth be told, it really isn't needed — the maximum magnification that the telescope can achieve is 300x, so using the Barlow with the 4 mm eyepiece, for example, causes images to become blurred.
Budget telescopes and cheaper models are often great options for people to try their hand at astronomy but don't come with high-end optical quality, as we discovered in our Celestron PowerSeeker 127 EQ review. So you may have to bear the PowerSeeker 127 EQ's limits in mind when looking for custom eyepieces and Barlow lenses.
Skywatchers must be comfortable using an equatorial mount and slow-motion controls. Polar aligning knowledge would be advantageous also before considering the PowerSeeker 127 EQ. If that's the case for you, this reflector is a reliable instrument for observing — and more so if the mirrors are collimated often.
- Read our Celestron PowerSeeker 127 EQ review
Encalife has teamed up with telescope makers SVBONY to deliver a lightweight, extremely affordable portable refractor telescope. The 400mm focal length is the perfect length for moon observations.
Light gathering through the telescope is reasonable using the 2.75-inch (70mm) aperture. A K20mm eyepiece that ships with the 501P provide a medium power view through the scope.
It also ships with plenty of accessories as well to save you from having to buy extras which we found handy when we reviewed the Encalife SVBONY 501P 70. They include a 45-degree 1.25-inch erect image diagonal, a 5x24 finderscope, a sturdy aluminum tripod, and a bag to carry it all in. At just 6.5lbs it's super lightweight which means traveling with it to dark sky locations is easy, though don't expect to zoom in to too many star clusters due to the limited focal length.
Encalife often have deals and discounts at events such as the Black Friday Sales and Amazon Prime Day so keep your eyes peeled for bargains around these times.
- Read our Encalife SVBONY 501P 70 review
Best Computerized or GoTo telescopes
The first of two of the NexStar telescopes on this list, and for a good reason. The Celestron NexStar 8SE can offer beginners a simple way to view the night sky without needing prior knowledge while providing intermediate and advanced sky watchers enough power to delve deeper into space or even pair it with a camera to produce awe-inspiring astro imagery.
When you pay big money for telescopes, you're usually guaranteed to get exceptionally high-quality optics that provide incredible views of a variety of astronomical targets.
Celestron's NexStar 8SE is no different, earning itself the title of 'the World's most beloved telescope' and the number one bestseller on B&H Photo (opens in new tab). Featuring a StarBright XLT (opens in new tab)(opens in new tab) optical coating, spectacular views of the planets and moon can be seen with excellent contrast and clarity. Jupiter, its moons, Saturn, and its rings are particularly breathtaking through the optical system. No chromatic aberration — or color fringing — can be seen around bright targets, and, what's more, excellent views of the deep-sky objects are within reach of the eight-inch (203.2 mm) aperture.
In our Celestron NexStar 8SE review, we walked you through what it's like to get everything set up, and it's very straightforward. No prior knowledge of the night sky is needed, as you can use Celestron's SkyPortal app or any other stargazing app to help you find two stars for the alignment process.
Once aligned, you can 'ask' the telescope, using the chunky hand-held controller, to slew automatically to any object in its vast database including planets, galaxies, double stars, star clusters, nebula and so on. There is even a 'sky tour' that automatically slews the scope to different extraterrestrial objects for you to enjoy, another fantastic feature for beginners or simply those who can't decide where to look.
The motor is smooth, and the results are accurate. Automatic tracking is a dream for astrophotographers who can take steady long exposures for post-shoot stacking to take stunning images.
The only real downside to the Celestron NexStar 8SE is the price tag. It's a significant purchase if you are merely 'interested' in the solar system, but it is excellent value for money if you're invested in skywatching or astrophotography for the long haul.
- Read our Celestron NexStar 8SE review
The Vaonis Stellina telescope is very different from most other telescopes on the market, it doesn't even look like a telescope, something that traditionalists will probably steer clear of! The Stellina's smart design means that it doesn't require the use of finderscopes and eyepieces. Instead, it makes use of a Sony CMOS (complementary metal-oxide-semiconductor) sensor and navigation via a smartphone to reveal breathtaking views and take jaw-dropping color images of the night sky. This telescope is undoubtedly more costly than competitor models but it does include a free download of Stellina app with a database of 100 targets to explore at the touch of a button.
Given the wide-angle sights the Stellina offers, this telescope isn't ideal for studying the planets, although the views are fair. Instead, it excels in providing images of bright deep-sky targets and the surface of the moon. Star clusters, select nebulas and galaxies are within easy reach through the optical system and we are, in particular, blown away by views of the Andromeda Galaxy (Messier 31). Decent clarity can be had, while 6.4MP images with a resolution of 3096 x 2080 are produced in JPEG and RAW format — the former being a great option to share on social media in Ultra HD.
In our in-depth review of the Vaonis Stellina, we found that it is a fabulous option for those interested in astrophotography above anything else, or for group viewing as up to 10 smart devices can be connected at once. It has a built-in light pollution filter to suppress urban skyglow, offers precise tracking and adapts well to changes in weather conditions.
There's no hiding the fact this model is pricey, but that's expected given its sophisticated technology, sturdy and stylish build and importantly, reliability.
- Read our Vaonis Stellina review
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As an introduction to the world of GoTo skywatching, the Sky-Watcher Skymax 127 SynScan AZ (opens in new tab) is a must-have for observers on a tighter budget. The SynScan AZ hand controller offers information on over 40,000 astronomical objects, which includes the most complete catalogs (Messier, NGC, IC and SAO) of deep-sky and solar system targets.
The astronomer has everything they need for a successful night under the stars: good quality star diagonal, 2x Barlow with a camera adaptor, 6x30 finderscope, a stainless steel tripod and an accessory tray.
Assembling the instrument is easy and, given the weight of 39.7 lbs. (18 kg), the Sky-Watcher Skymax 127 SynScan AZ is light enough to carry across the backyard without a great deal of effort. Skywatchers have the choice of powering the Servo Drive with 8 AA batteries or a 12V power supply — because batteries tend to drain quickly in when it's cold, we recommend investing in the latter for uninterrupted observations with the SynScan technology.
Alignment is simple, using two stars to set the instrument up, but beginners may need practice in getting this just right — we recommend becoming acquainted with the Skymax 127 during daylight hours while ensuring that you read the supplied manual from cover to cover.
In terms of optical prowess, we don't have any complaints. We can fit a waxing gibbous moon phase in the field of view and, after tweaking the focuser, the craters and lunar mare come into exquisite focus, contrast and clarity. A moon filter offered even better sights. Slewing over to the star-forming region, the Orion Nebula (Messier 42), is also picked out easily with the 5-inch (127 mm) aperture — it appears as a dusty patch of light with the Trapezium Cluster's member stars dazzling with brilliant clarity at the nebula's heart.
A minor niggle is the unstable stainless steel tripod, so we recommend supporting the setup by hand while slewing and in windy conditions.
- Need more advice? Here's our specialized guide to the best telescopes for beginners
Celestron's range of NexStar telescopes has a well-deserved reputation for excellent optics, user-friendly assembly and a plethora of features, and the telescope exemplifies all of these which we outlined when we conducted our Celestron NexStar 6SE review exemplifies all of these.
The 5.91-inch (150 mm) aperture is a step up from the Meade StarNavigator NG 114 in light-gathering prowess, while the more than 40,000 astronomical objects in the NexStar+ hand controller's database mean you'll never run out of new targets to seek. However, skywatchers should be mindful that extra eyepieces will need to be added to capture them, and even then, the aperture won't show all targets listed in the database in great detail.
You can use 'tour mode', where the NextStar 6SE carefully guides you through different night sky targets, either in a specific constellation or right across the sky. It's a brilliant feature for people who can't decide what to observe or just want to explore the night sky like they never have before.
The SkyAlign technology is simple to use and gets you pointed in the right direction, fast. The motorized mount also has nine slewing speeds on top of its different tracking rates. All of this sounds brilliant, and it is, but there is a downside. The NexStar 6SE's battery can drain very quickly, which isn't ideal, so we recommend powering the setup with an external power source.
Imagers may initially be displeased with its slow f/10 focal ratio, limiting the NexStar 6SE to being a planetary or lunar imager at best, but there is the facility for more advanced users to switch out the secondary mirror for their camera, with the smaller light path increasing the focal ratio to an astrophotography-friendly f/2.
- Read our Celestron NexStar 6SE review
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The larger the aperture of your telescope, the more light it will gather, allowing you to resolve the finer details in astronomical objects, and see deeper into the universe. With a 12-inch (305 mm) objective, this collapsible Dobsonian from Sky-Watcher lives up to the tag of 'light bucket.'
Dobsonians are designed for their simplicity and, with its GoTo capability plus motorized rocker alt-azimuth mount navigated by a SynScan hand controller, getting great views of the night sky and calibrating the telescope has never been easier.
Over 40,000 targets are offered in the database and, we have to say, that seeking out faint fuzzies was our first port of call with the Sky-Watcher Flextube 300 SynScan. The Andromeda Galaxy (Messier 31) is an incredible sight, with some dust lanes visible and the bulge glowing brightly. Its satellite galaxies are also visible as points of light in the field view.
With a focal ratio of f/4.9, this Dobsonian is fast enough for imagers to use all the photons it will collect. With a little skill, you'll be able to take some amazing images through this telescope.
Although the Sky-Watcher Flextube 300 SynScan is heavy, its collapsible design makes it easier for you to fit in the trunk of your car whenever the need arises to seek out dark-sky parks or attend star parties.
It has a hefty price tag, but given the aperture, imaging prowess and GoTo capability of the Sky-Watcher Flextube 300 SynScan, it's a must-buy for hobbyists.
Best telescopes for observing planets
The Orion Skyline 6" (opens in new tab) telescope is a great choice for beginner and intermediate astronomers alike due to its easy-to-use nature and high-quality optics.
In terms of those optics, you get an objective lens of 152mm meaning plenty of light will pass through, making night sky targets more visible. The telescope also comes with multi-coated optics, so those night sky targets can be seen with absolute clarity. The focal length is also a huge plus, 1200mm means you can see the finer details of your targets like craters in the moon and other planets.
Magnification also goes up to 133x which means it's a powerful telescope, you won't miss out on the finer details of celestial objects. So if you want to view objects like the moon and planets, this level of magnification, especially with the eyepieces supplied, is really helpful.
It's also well built and easy to use, a huge plus for those without bags of astronomy experience. However, you can get alternatives for a lower price, even if they don't quite match the Skyline 6-inch for quality of specs. We also like the Orion AstroView 90 (opens in new tab) a lot, for which this is a suitable replacement, however, it's hard to find it in stock online.
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The Celestron Omni XLT 102 is aimed at intermediate-level skywatchers, particularly those who have mastered setting circles and know how to use the right ascension and declination coordinates on the supplied high-quality CG-4 German equatorial mount.
The Omni XLT 102 features high-quality optics, painted with Celestron's StarBright XLT coating to maximize light transmission. The optical system also makes use of aspheric shaping technology to minimize spherical aberration, a visual defect where incoming light is focused at different points.
As such, the Omni XLT 102, with its mix of aperture and f/10 focal ratio, is able to produce excellent views of the planets, from Jupiter's atmospheric bands and moons, to Saturn's rings and craters on the moon, showing great contrast between areas in shadow and those bathed in daylight. While there is a slight amount of color fringing, views through the optical system are outstanding.
The refractor comes with a 25 mm eyepiece, 1.25-inch star diagonal, heavy-duty stainless steel tripod, accessory tray, spirit level, Starry Night Special Edition (opens in new tab) software and a 6x30 finderscope.
Best astrophotography telescopes(opens in new tab)
Celestron’s EdgeHD technology turns Schmidt-Cassegrain telescopes into high-quality astrographs with perfectly flat fields. The way that the Schmidt-Cassegrain optics focus light usually means that the focal plane — where the light comes to focus — is curved, but if you are imaging, your CCD camera's sensor is flat. A curved focal plane on a flat CCD sensor results in field curvature, where stars at the edge of the field become blurry. An undesirable effect for astrophotographers.
In our Celestron Advanced VX 8 EdgeHD review, we found the EdgeHD optics negate this, creating a perfectly flat field right to the edge of the frame for pinpoint sharpness right across the image. We are impressed with the optical performance that the Celestron Advanced VX 8 EdgeHD delivers, with crisp and clear views with no optical distortion or false color.
As an added bonus, the optical tube assembly comes packaged with Celestron’s Advanced VX mount, which is tailor-made for imagers, capable of photographing across the meridian without needing to do a meridian flip. The setup also performs periodic corrections to remove errors when tracking objects and also comes with an autoguider port.
The Celestron Advanced VX9.25 EdgeHD can carry a load of 30 lbs. (13.6 kilograms) too, so the tube and all your imaging accessories are fully supported. Also included is the standard NexStar+ hand controller, a 40 mm eyepiece, and access to Celestron’s SkyPortal app (opens in new tab) and Starry Night Special Edition software (opens in new tab). Check out our Celestron deals page to see if you can snap up a bargain.
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An excellent telescope for the beginner or those on a budget, the Celestron Inspire 100AZ is a great choice for those looking for a complete package that offers more in the way of accessories over most starter telescope bundles.
The Inspire 100AZ comes with a 90-degree erect image diagonal with a 1.25-inch fitting that makes the telescope suitable for terrestrial and celestial views, a pair of eyepieces (20 mm and 10 mm), red LED flashlight, accessory tray, StarPointer Pro finderscope and a smartphone adapter for basic astrophotography. Given the refractor's focal ratio, the Inspire 100AZ is limited to short exposure photography.
A degree of false color and blurring in the field of view was detected during our observations. The latter is easily resolved with a careful selection of eyepieces, so we recommend investing in further eyepieces to make the most of the Inspire 100AZ's optical system and to ensure that it does translate to your photos. False color, on the other hand, is to be expected in telescopes at this price point but it did not ruin the experience.
During our Celestron Inspire 80AZ review we were particularly impressed with the overall build of this refractor — the StarPointer is a pleasant surprise since it's able to pick out faint stars under moderate light pollution for an accurate experience in hopping from one target to another.
- Read our Celestron Inspire 100AZ review
For those who fancy kicking things up a notch, the Encalife SVBONY 503 refractor takes you close to deep-sky objects with its impressive 560mm focal length. A 3-inch (80mm) aperture drinks in the light and multiple accessories for this series of telescopes means astrophotography, including of deep-sky objects is at your fingertips.
This scope is compact compared to some other refractors, and while still huge, it is light and small enough to take out and about to find the best dark skies. This series of telescopes also offers multiple accessories to enhance your stargazing or astrophotography experience.
Encalife created the SVBONY SV503 to last, with substantial build quality that feels robust to the touch. Not only that, it is attractively finished with a white powder coat with gold accents on the micro-focuser and at the end of the retractable dew shield.
If you're interested in this scope, you'll probably be wise to wait for the upcoming Black Friday sales as Encalife will likely substantially drop the price on this scope as they did for Amazon Prime Day.
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Sky-Watcher (opens in new tab)'s Skymax 150 is a great package for the price, with some models offering a high-quality equatorial mount for short-exposure astrophotography and long-exposure imaging. This well-constructed Maksutov-Cassegrain also comes with a single eyepiece with a focal length of 28 mm for a magnification of 64x.
Weighing in at 13.23 lbs. (6 kilograms), the Skymax 150 is suitable for most regular equatorial mounts — many makes and models will be able to take the load of both the telescope and extra accessories, including CCD or DSLR cameras, filter wheels and other such add-ons. For versatility in the type of mount you choose, a Vixen-style dovetail plate is supplied for a moderate price tag.
The Skymax 150's optical prowess is outstanding, with no sign of optical distortion. The telescope is a great all-arounder, suitable for imaging everything from the planets to deep-sky galaxies and nebulas — and as you would expect for a telescope designed for giving great images. As an added bonus, the instrument is a breeze to use and accessorize.
The focuser is lovely and smooth to operate and the Skymax 150 keeps a good amount of fine focus once it's been found — vital for those long imaging sessions.
How we test the best telescopes
To guarantee you're getting honest, up-to-date recommendations on the best telescopes to buy here at Space.com we make sure to put every telescope through a rigorous review to fully test each instrument. Each telescope is reviewed based on many aspects, from its construction and design, to how well it functions as an optical instrument and its performance in the field.
Each telescope is carefully tested by either our expert staff or knowledgeable freelance contributors who know their subject areas in depth. This ensures fair reviewing is backed by personal, hands-on experience with each telescope and is judged based on its price point, class and destined use. For example, comparing a 10-inch Dobsonian to a 2.76-inch refractor wouldn't be appropriate though each telescope might be the best pick in their own class.
We look at how easy it is to set up, whether computerized or motorized mounts are reliable, accurate and quiet. If a telescope comes with appropriate eyepieces and tripods, we also suggest if a particular telescope would benefit from any additional kit to give you the best experience possible.
With complete editorial independence, Space.com are here to ensure you get the best buying advice on telescopes, whether you should purchase an instrument or not, making our buying guides and reviews reliable and transparent.
Telescope buying advice
Aperture: Diameter of the primary mirror or lens, which allows a telescope to collect light.
Field of view: Area of sky visible through the eyepiece.
Focal length: A telescope's tube length. Short focal lengths offer a wide field of view and a small image.
Focal ratio: Also known as the telescope's speed. Small focal ratios provide lower magnifications, wide field of view and a brighter image.
Magnification: Relationship between the telescope's optical system and the eyepiece.
The aperture size is one of the most important things to consider when purchasing a telescope, then you should next consider the focal length. The main thing to remember here is that bigger isn't always better.
It really all comes down to what subjects you want to view. Shorter focal lengths, say of about 20 inches (500 mm), will provide a field of view for you to take in large areas of the Milky Way and showpieces such as the Pleiades (Messier 45) and Orion Nebula (Messier 42). Meanwhile, high-power objects like the moon, planets or double stars need a telescope with a longer focal length of about 80 inches (2000 mm).
If you can't really decide, then there are plenty of compromises between aperture and focal length but you must be willing to make a few trade-offs in terms of the weight of your instrument, the field of view and its 'power.' Read on for what you can expect from the three major kinds of telescope: the refractor, reflector and catadioptric.
As their name suggests, refractors bend (or refract) the light that they gather to give you a view of your astronomical target. As telescopes go, they have a fairly straightforward assembly and consist of a main objective lens at one end that focuses light through to the other.
Intuitive to use, the refractor is often a popular choice of instrument for novice astronomers since they require little maintenance and are usually affixed to the simple alt-azimuth mount, which allows the skywatcher to slew from left to right and up and down in order to locate the desired target. Being easy to use means that these telescopes are also simple to manufacture, making them cheaper to buy with price points increasing with aperture size.
Refractors are particularly good at giving highly magnified and high contrast images and, because of this, are ideal instruments to use when looking at solar system targets such as the moon and the planets. The best refractors usually have an aperture of two inches (60 mm) or more and will provide reasonable views of astronomical objects. If you're looking for a larger aperture, then a three- or four-inch (80 mm to 90 mm) will suit you best.
The drawback of a refractor is that they can suffer from chromatic aberration, also known as color fringing. When a single lens doesn't focus all of the colors emitted from a target object at the same point, bright objects such as the moon, Venus or Jupiter usually have a colored halo around them. Many refractors are manufactured as achromatic or apochromatic (also known as Extra Dispersion (ED) telescopes) to reduce this problem.
The achromatic refractor is cheaper than the apochromatic refractor and, combined with its efficiency, is often the type of telescope that novice astronomers go for. Even if you decide to go for the more expensive achromat, you're still likely to get a stubborn degree of purple fringing around some targets.
Unless you're a seasoned skywatcher and you can afford to go for the more expensive apochromat — which corrects for such an effect by using exotic glass for the lenses — this degree of color fringing will not ruin your observing experience to any great extent. If you decide to go for the expensive option, you will be stunned by the views you will get through these excellent telescopes.
Be warned though: you might find that some apochromats come without a tripod, something that you'll have to buy separately along with any accessories — so be sure to choose wisely.
There are two common types of reflector telescope — the Newtonian and the Dobsonian. However, the way these instruments operate is exactly the same — they both use mirrors to reflect light to create an image of the object you're looking at.
The Newtonian telescope comprises a curved-light collecting mirror, which can be found at the tube's base. The light that hits this mirror is reflected back to the front of the tube, where a smaller flat mirror — orientated at 45° — brings light to the observer who can see their chosen object.
The Newtonian can be found on alt-azimuth mounts, but you shouldn't be too surprised to find this type of reflector is more popularly affixed to an equatorial mount, allowing the telescope to follow the rotation of the sky while being aligned with your hemisphere's celestial pole. This reflector is a favorite in the amateur astronomy community due to its versatility by observing a wide selection of astronomical targets and allowing for astrophotography. With Newtonians, you can also buy a large aperture for less money — for instance, an eight-inch (203.2 mm) reflector would cost you less than a refractor with the same aperture, allowing you to get much more value for your money.
On the downside, the Newtonian doesn't come hassle-free, especially regarding maintenance. You might find yourself having to have optical mirrors realigned as well as the mirror's surfaces repainted since they can eventually become tarnished. If you choose to go for a reflector of this sort, you should always choose one with mirrors with a protective coating — these will last longer.
Some beginners to the hobby of astronomy might find setting up and using an equatorial mount tricky and that's where the Dobsonian comes in. These telescopes give the capabilities of a reflector without the complexities an equatorial mount will bring since it employs an alt-azimuth mount. Dobsonians are very simple to use and can easily be pulled into orientation when looking at astronomical objects. If you're not confident in navigating your telescope though, then GoTo or computerized Dobsonians and Newtonians are on the market — but at a higher cost.
Whatever reflector you choose, these telescopes are excellent for low-magnification targets such as galaxies and many types of nebulas.
Maksutov-Cassegrain and Schmidt-Cassegrain (catadioptric telescopes)
To get the best of both reflectors and refractors, manufacturers developed the Schmidt-Cassegrain and the Maksutov-Cassegrain telescopes. These catadioptric telescopes generally correct issues found in refractors and reflectors.
The Maksutov-Cassegrain corrects the problem that the reflector experiences — an aberration effect called 'coma', which can make objects look distorted and appear like they have a tail. This effect is reduced or banished with the combined efforts of a mirror and a corrector lens. The Maksutov is ideal for beginners or for those who don't have the time (or money!) to complete any extensive maintenance on their instrument since the tube's optics are sealed off.
This catadioptric is very robust and is also the ideal family telescope. Packed into its short optical tube is a system that allows you to target higher magnification objects such as the planets, moon and double stars. You'll be able to pick up a Maksutov for a very good price and, if you struggle to find objects and your way around the night sky, then both this type of catadioptric telescope and the Schmidt-Cassegrain can be found in abundance and equipped with a GoTo system.
What you get with a Schmidt-Cassegrain is very similar to the capabilities of the Maksutov. It will allow you to make general observations of planetary targets and stars. It is also possible to expand the telescope's field of view with the help of corrector lenses, allowing you to view a wide selection of astronomical targets.
The catadioptric telescope is also suitable if you want to try astrophotography, but combine this with their marked improvement on your standard telescope and you should expect a substantial rise in cost compared to standard reflect and refractors.