NexStar 90SLT is a compact 90mm Maksutov-Cassegrain with computerised GoTo pointing for detailed lunar, planetary and terrestrial viewing. It is supplied as a complete visual-observing system with optical tube, computerised mount, tripod, hand control and essential accessories.
Computerised GoTo Observing with SkyAlign
The NexStar+ hand control can locate and track objects from its database of more than 40,000 targets. Celestron's SkyAlign procedure allows the mount to determine its position after it is centred on three bright celestial objects. Other alignment routines remain available when preferred.
The single-arm altazimuth mount is intended for straightforward visual observing. It tracks objects as they move across the sky, while nine selectable slew speeds provide both rapid movement and fine centring control.
Maksutov-Cassegrain Optics
The 90mm (3.54 inches) optical system has a focal length of 1250mm and a focal ratio of f/14. It is particularly suited to the Moon, planetary detail, double stars and bright deep-sky objects, while its compact folded optical path also suits daytime terrestrial observation.
Portable, No-Tool Setup
The optical tube connects to the mount through a quick-release dovetail arrangement, and the mount sits on an adjustable stainless-steel tripod. The quick-release design and accessory tray allow the system to be assembled without specialist tools.
The telescope can be powered by eight AA batteries or a suitable regulated 12V DC supply. Batteries and an external mains or portable supply are not stated as included.
Included Eyepieces and Finder
Two 1.25-inch eyepieces provide lower- and higher-power viewing, while the StarPointer red-dot finderscope helps centre alignment stars and observing targets. Exact included eyepiece details are stated in the specification table and accuracy note where Celestron's current source data conflicts.
Optional App and Automatic Alignment Upgrades
The SLT mount can be used with compatible optional Celestron accessories such as the SkyPortal WiFi Module and StarSense AutoAlign where Celestron lists compatibility. These accessories are sold separately and are not built into the telescope.
The included Starry Night Special Edition software can assist with learning the sky and planning observing sessions.
What Is Included?
- 90mm Maksutov-Cassegrain optical tube
- Computerised SLT single-arm mount
- Adjustable stainless-steel tripod and accessory tray
- NexStar+ hand control
- 25mm and 9mm eyepieces
- StarPointer red-dot finderscope
- 1.25-inch star diagonal
- Starry Night Special Edition software download
Specifications
Optical Tube
| Optical design | Maksutov-Cassegrain |
|---|---|
| Aperture | 90mm (3.54 inches) |
| Focal length | 1250mm |
| Focal ratio | f/14 |
| Optical coatings | Fully coated |
| Included eyepieces | 25mm and 9mm |
| Stated eyepiece magnifications | 50× and 139× |
| Highest useful magnification | 213× |
| Lowest useful magnification | 13× |
| Limiting stellar magnitude | 12.3 |
| Rayleigh resolution | 1.55 arcseconds |
| Dawes resolution | 1.29 arcseconds |
| Light-gathering power | 165× compared with the human eye |
| Finderscope | StarPointer red-dot finderscope |
Mount, Control and Power
| Mount | Computerised altazimuth single fork arm |
|---|---|
| Tripod | Adjustable stainless-steel tripod with accessory tray |
| Hand control | NexStar+ computerised hand control |
| Database | More than 40,000 objects |
| Alignment | SkyAlign, Auto Two-Star, One-Star, Two-Star and Solar System Align |
| Tracking rates | Sidereal, Solar and Lunar |
| Slew speeds | Nine |
| Power | 12V DC or 8 AA batteries; batteries and external power supply are not included |
| Shopify shipping weight | 12.701kg — official Celestron UK product-variant record |
Solar Safety
Warning: Never point this telescope towards the Sun without appropriate specialist solar equipment.
Solar observing requires a suitable certified full-aperture solar filter securely fitted over the front aperture. Never use an eyepiece-type solar filter and never project an image of the Sun. Unfiltered sunlight can cause permanent eye damage and damage the telescope.
If suitable compatibility and safe installation cannot be confirmed, do not point the telescope at or near the Sun.
Instruction Manuals
Use the official Celestron instructions before assembly, alignment and first use.