Celestron StarSense Explorer DX 102AZ Refractor Telescope

A 4" refractor that uses your phone your phone to find galaxies, nebulae and planets

The Celestron StarSense Explorer DX 102AZ is a 102mm (4") refractor on a manual alt-azimuth mount with Celestron's StarSense smartphone dock. Clip your phone into the dock, open the free StarSense Explorer app, and it builds a list of what's up tonight and guides you to each object. It's one of the telescopes we recommend most often for families and first-time observers, and the whole kit weighs 14.2lb (6.4kg).

Key specs: 102mm (4") refractor · 660mm focal length, f/6.5 · 25mm (26x) and 10mm (66x) eyepieces · highest useful magnification 240x · StarSense smartphone dock · manual alt-az mount with slow-motion controls · 49" aluminum tripod · 14.2lb total

The StarSense Explorer DX 102AZ is on display in our Denver store, so you can see it in person before you buy.

What you'll see

• The Moon: craters, mountain ranges and the long shadows along the terminator.
• Planets: Saturn's rings, Jupiter's cloud belts and four largest moons, the phases of Venus, and Mars near opposition.
• Star clusters: the Pleiades, the Double Cluster in Perseus and the Hercules Cluster (M13), which this scope's wider field frames nicely.
• Nebulae and galaxies: the Orion Nebula from the city, and the Andromeda Galaxy, the Ring Nebula and the Dumbbell Nebula from darker skies.

How it works

Put your phone in the StarSense dock and align the dock to the telescope once, using a bright star or a distant object in daytime. It takes about 2 minutes. After that, the app recognizes star patterns through your phone's camera, works out where the telescope is pointed, and shows arrows that lead you to your target. When the bullseye turns green, it's in the eyepiece. The app also explains what you're seeing.

The mount has slip clutches and slow-motion knobs on both axes, so you can swing it quickly and then make small moves to follow an object as it drifts. The telescope needs no power. Celestron lists the current app as compatible with iPhone XR or newer (iOS 18+) and Android 12 or newer, so check your phone on Celestron's compatibility page before you buy.

Using it in Colorado

• City skies: the Moon, planets, bright clusters and the Orion Nebula all look good from a Denver backyard.
• Cold nights: your phone battery drains faster in the cold, so keep a USB power bank in your pocket.
• Camping trips: at 14.2lb, it rides easily in the car to a dark site, where galaxies and fainter nebulae show up.

What to add for the best results

• Celestron X-Cel LX 7mm eyepiece: 94x, a good planet power with comfortable eye relief.
• Celestron 2x Omni Barlow: doubles both included eyepieces to 52x and 132x.
• Celestron Omni 32mm eyepiece: 21x with about a 2.5° field, wide enough for the whole Pleiades or Andromeda's core.
• Moon filter: cuts the glare of a bright Moon.
• NexYZ DX smartphone adapter: holds your phone at the eyepiece for photos of the Moon and planets.

StarSense Explorer DX 102AZ vs. similar telescopes

See every model in our Celestron StarSense Explorer collection.

What's in the box

• 102mm refractor optical tube
• Manual alt-azimuth mount and tripod (preassembled) with accessory tray
• 25mm and 10mm 1.25" eyepieces
• Erect-image 90° star diagonal
• StarSense smartphone dock
• StarPointer red-dot finder

Extra eyepieces, filters and a phone power bank are sold separately.

Celestron StarSense Explorer DX 102AZ FAQ

Is it good for beginners?

Yes. The app removes the hardest part of starting out, which is finding things, and a refractor needs no maintenance.

Can I see Saturn and Jupiter?

Yes. Saturn's rings are clear at 66x with the included 10mm eyepiece, and Jupiter's cloud belts and moons show well. A 7mm eyepiece (94x) or a 2x Barlow brings them in closer.

DX 102AZ or DX 130AZ?

The DX 130AZ gathers about 60% more light, so faint galaxies and nebulae look brighter, but its mirrors need occasional collimation. The 102AZ is lighter, needs no adjustment, and works in daytime with the right-side-up diagonal.

Does it track objects automatically?

No. The mount is manual. You aim by following the app's arrows and use the slow-motion knobs to keep objects centered.

Does it need batteries or power?

No. Only your phone uses power.

Can I use it for astrophotography?

You can take phone photos of the Moon and bright planets with a smartphone adapter. Deep-sky imaging needs a tracking mount, so for that we'd point you to a smart telescope like the Seestar S30 Pro.

Can I see one before I buy?

Yes. The DX 102AZ is on display in our Denver store.

Specifications