Saturn was only a night past its annual opposition when I pointed the Celestron StarSense Explorer 150mm Tabletop Dobsonian straight at it. The planet was at its biggest and brightest of the year, the seeing was good and its famous rings were visibly opening up after appearing edge-on from Earth in recent years. It was an obvious target for a new telescope.
Finding it took seconds. After selecting Saturn in Celestron’s StarSense Explorer app, I followed the on-screen arrows as I moved the telescope across the sky. As I got closer, the app zoomed in until a bullseye turned green. I looked through the supplied 25mm eyepiece, then swapped to the 10mm to see a pale yellow Saturn at 75x magnification, with its rings sharply defined and its giant moon Titan visible in orbit.
(Image credit: Jamie Carter)
It was a stunning view, and exactly the kind of experience a beginner needs from a first telescope. There was no frustration and no wondering whether I was looking in the right place. StarSense took me straight there — but, crucially, I moved the telescope myself. I’ve always liked that combination of hand-holding and DIY observing that Celestron’s StarSense tech gives you.
I’m less convinced by the tabletop telescope it’s attached to. Although this $599 RRP (£379) model is significantly smaller than the Celestron StarSense Explorer 8-inch Dobsonian telescope I’ve previously reviewed, it still weighs 25 lbs (11.33 kg). You need to place it on something sturdy before you can use it comfortably. After living with it in my backyard, I’m not convinced the tabletop format is the advantage it initially appears to be.
What StarSense Explorer does well
I’ve used Celestron’s StarSense Explorer system on a variety of telescopes and have always been impressed by how easy this type of smartphone navigation is to use. The technology works just as well here and, for me, it remains one of the best ways of making a traditional optical telescope accessible to a complete beginner.
This isn’t a computerized GoTo telescope. There are no motors to slew across the sky automatically and no tracking system to keep an object centered. Instead, a smartphone sits in a dock attached to the telescope, and its camera looks at the sky via a small mirror. Celestron’s StarSense Explorer app analyzes the reflections of the stars it sees, works out exactly where the telescope is pointing and tells you which direction to push it to reach the object you want to observe.
My iPhone 16 Pro Max fitted perfectly into the dock, and the initial alignment process was identical to what I’d used before. Once that was done, I used StarSense to find the Pleiades (M45), the Andromeda Galaxy (M31), the Double Cluster in Perseus and Saturn. It worked every time, with the target appearing in the eyepiece when the app told me I had reached it.
I can find all of those objects without an app, but that’s not really the point. Beginners often struggle to translate a star chart or an astronomy app into actual telescope movements. StarSense gives you confidence that you’re heading in the right direction while still requiring you to operate it physically.
That makes it a useful way to learn the night sky. After repeatedly pushing the telescope from one familiar object to another, you begin to understand how everything fits together. That’s very different from pressing a button and watching a GoTo or smart telescope move itself, and it’s why I think StarSense is worth paying extra for, even on a relatively wide-field telescope like this one.
The 5.9-inch mirror produces lovely wide-field views
The StarSense system may be the headline feature, but the reason to buy any Dobsonian is aperture. This one uses a 150mm (5.9-inch) parabolic primary mirror with a 750mm focal length and a relatively fast f/5 focal ratio. That combination gives it fairly low-power, wide-field views that are particularly well suited to large star clusters.
The Pleiades was one of my favorite views. At 30x through the supplied 25mm eyepiece, the telescope gave me a sharp field of stars and a particularly good view of what I call “Carter’s Whip” — the curving line of stars running through the cluster. I saw little obvious softness towards the edges, and focusing was straightforward.
The Andromeda Galaxy (M31) was a different proposition. From my light-polluted backyard, I could see Andromeda’s bright core, but not its outskirts or its satellite galaxies. That’s largely a consequence of observing a galaxy from a city, not a criticism of a 150mm telescope, but it’s a useful reminder of what visual astronomy is actually like. Don’t expect the colorful, detailed views of galaxies and nebulas you see in astrophotos, such as the stacked images a smart telescope can give you.
Saturn was more rewarding, but I would have liked more magnification when the seeing was this good. Add a Barlow lens if planets are a priority — it can double the magnification of any eyepiece you use it with.
Overall, I was impressed by the telescope’s optics. The views were sharp and contrast-y, and there’s enough aperture here to make a serious start in visual astronomy. However, the two supplied 25mm and 10mm Kellner eyepieces are decidedly entry-level — and obvious candidates for upgrading in the medium term.
The focuser is a weak point. It’s a fairly basic 1.25-inch rack-and-pinion design, but I noticed some wobble and vibration while using it. That’s a shame because the focuser is one of the parts of a telescope you constantly interact with, and something smoother and more precise would make the entire instrument feel more accomplished.
(Image credit: Jamie Carter)
A tabletop telescope needs the right table
The tabletop design isn’t necessarily as convenient as it sounds. I expected this scope to feel considerably more convenient than Celestron’s 8-inch StarSense Dobsonian. The base has built-in grab handles, but the assembled telescope’s shape and weight make it awkward to lift onto a table — I certainly wouldn’t recommend it to anyone with a bad back. You could move the optical tube and base separately, but that starts to cancel out the convenience of owning a relatively compact tabletop telescope.
You also need to choose your table carefully. It has to be sturdy enough not to introduce vibrations, but not so large that you have to stretch across it to reach the eyepiece as the telescope points to different parts of the sky. I found myself bending and stretching into some awkward positions.
Once it’s in position, the Dobsonian mount worked well. The balance was good, and I didn’t need to adjust the altitude tension, while the movements offered a useful mix of resistance and fluidity as I followed StarSense around the sky. At 75x, however, keeping Saturn centered was more difficult than I expected. It was easy to over-nudge the telescope, then correct in the opposite direction.
Celestron sells an optional tripod for the telescope, and after using the tabletop base, I can see why that might be attractive. However, I’d personally rather put the money towards a larger Dobsonian whose base is designed to sit directly on the ground.
Putting it together was harder than using it
This scope doesn’t arrive in one piece. Assembly took about 90 minutes, and it required all manner of screws and screwdrivers. The main problem was getting the screws into the holes in the Dobsonian base, which took so much effort that I ended up with a blister on my hand. That’s not what I expected from a telescope aimed at beginners, especially when almost everything about using it has been designed to make things easy.
Once built, things improved considerably. My review sample arrived well collimated, so I didn’t have to adjust the mirror alignment. The tube rings, phone dock and general construction were all good enough for a telescope at this price, and nothing about the telescope felt particularly fragile. Once the telescope is outside, on a suitable table and aligned, it’s an impressively straightforward instrument to use.
Why I would still choose the 8-inch version
The more I used the StarSense Explorer 150mm Dobsonian, the more I wondered who really benefits from the tabletop format. It’s certainly smaller than Celestron’s 8-inch StarSense Explorer Dobsonian, but it’s still a substantial object to store, and I didn’t feel any more inclined to grab it for a quick observing session.
Going bigger offers an optical advantage. An 8-inch/203mm aperture collects about 83% more light than a 150mm aperture, which matters when you’re observing faint deep-sky objects. The 8-inch StarSense also had a much nicer 2-inch Crayford focuser, and generally felt like a telescope with a little more room to grow into.
(Image credit: Jamie Carter)
Visual astronomy matters more than ever
Dobsonians are the perfect companion to smart telescopes. The latter have completely changed what beginners can photograph from their backyards, particularly under light pollution. They can reveal galaxies and nebulas that are extremely difficult or impossible to see visually. I use them all the time. But they are no substitute for navigating to and actually seeing objects in the night sky with your own eyes.
The two approaches don’t need to compete. A smart telescope has to be pointed and then left alone for an hour or four to stack images. That time could be spent pushing something like the StarSense Explorer 150mm Tabletop Dobsonian around the sky, and actually looking through an eyepiece at the same objects. One shows you far more than your eyes can detect, but the other lets you see the photons yourself — and make a human connection with the night sky.
Where the StarSense Explorer 150mm sits against its rivals
At $599 RRP (£379), the StarSense Explorer 150mm sits in an interesting part of the beginner telescope market. There are smaller tabletop Dobsonians like the Celestron Moon Mission 100mm without smartphone navigation, but I think StarSense is worth paying extra for, particularly for a first-time telescope owner.
If you mainly want to observe planets and the moon, a refractor like the Celestron StarSense Explorer LT 70AZ also makes sense. However, if you want to go relatively large, I do recommend the StarSense Explorer 150mm Tabletop Dobsonian — with an important qualification. Its optics are good, StarSense is superb, and it’s an excellent way for a beginner to learn their way around the night sky, but I’m not convinced that 150mm is the sweet spot for this particular design. It’s too big to feel genuinely convenient as a tabletop telescope, yet not big enough to deliver the full advantages of a larger Dobsonian.
If space is tight, this is a very capable first telescope. If you have room for the 8-inch StarSense Explorer, I’d go bigger.
