The Celestron NexStar 90SLT telescope combines a 90 mm Maksutov-Cassegrain optical tube with a computerized altazimuth mount. It also includes a steel tripod, NexStar+ hand control and two eyepieces for different viewing magnifications.
Celestron NexStar 90SLT telescope optics
The optical system folds the light path through a corrector plate and mirrors. As a result, the telescope has a compact optical tube. In addition, its focal length is 1,250 mm, with an f/14 focal ratio. For example, the supplied 25 mm eyepiece provides 50x magnification, while the 9 mm eyepiece provides approximately 139x.
Also, allow the optical tube time to adjust to the outdoor temperature before observing.
Computerized mount and alignment
The NexStar+ controller also provides a database of 40,000 objects. After alignment, the motorized mount can locate and track selected objects. First, assemble the quick-release mount and tripod. Then follow the supplied instructions for SkyAlign or another supported alignment procedure.
Included equipment
- 90 mm optical tube and computerized mount
- Adjustable steel tripod and accessory tray
- NexStar+ hand control
- StarPointer finder
- Star diagonal
- 25 mm and 9 mm eyepieces
- Starry Night Special Edition software download
Power and accessories
The telescope uses eight AA batteries, which are not included. Alternatively, use a compatible PowerTank or 12 V adapter, sold separately. However, before adding accessories, check their compatibility and power requirements.
Finally, compare the full specifications below before choosing your Celestron NexStar 90SLT telescope. You can also browse our astronomy collection for other viewing equipment.
Celestron NexStar 90SLT telescope specifications and solar safety
| Specification | Details |
|---|---|
| Optical system | Maksutov-Cassegrain; aperture 90mm (3.54"); focal length 1250mm (49"); focal ratio f/14 |
| Supplied eyepieces | 25mm (0.98") gives 50x; 9mm (0.35") gives 139x |
| Finder and diagonal | StarPointer™ red dot finderscope; star diagonal 1.25 |
| Useful magnification | Lowest 13x; highest 213x |
| Resolution | Rayleigh 1.55 arc seconds; Dawes 1.29 arc seconds |
| Light and magnitude | Limiting stellar magnitude 12.3; light gathering power 165x compared to the human eye |
| Field of view | Apparent 1°; linear field at 1000 yds is 53 ft (16 m) |
| Optical coatings | Fully Coated |
| Mount, tripod and tray | Motorized Altazimuth mount; Steel tripod; No Tool, Quick release accessory tray |
| Motion and tracking | Nine slew speeds; Sidereal, Solar and Lunar tracking rates; Alt-Az, EQ North and EQ South tracking modes |
| Alignment procedures | SkyAlign, Auto 2-Star Align, 1-Star Align, 2-Star Align, Solar System Align |
| Control and database | Fully Computerized / Flash Upgradeable hand control; NexStar+ 40,000 Object Database |
| Optional GPS | Optional SkySync GPS Accessory (93969) |
| Software | Celestron Starry Night Special Edition Software and SkyPortal App |
Solar safety
- Never look directly at the Sun with the naked eye or with an optic (unless you have the proper solar filter). Permanent and irreversible eye damage may result.
- Never use your optic to project an image of the Sun onto any surface. Internal heat build-up can damage the optic and any accessories attached to it.
- Never leave your optic unsupervised. Make sure an adult who is familiar with the correct operating procedures is with your optic at all times, especially when children are present.