Celestron NexStar 90 SLT Computerized Telescope - 22087

Designed to be an affordable entry level to mid-level computerized GoTo telescope, the NexStar SLT refractors, reflectors, and Maks are available in the most popular sizes and are loaded with valuable design features. With preassembled, adjustable stainless steel tripods, and quick release fork arms and tubes, NexStar SLT telescopes can be set up in a matter of minutes – with no tools required! You can see details of the lunar surface, Venus and its phases, polar caps on Mars, Jupiter and its four moons, Saturn with its rings plainly visible and much more!

Intelligent Design

The internal battery compartment provides power to the high precision servo motors for rigid low-vibration performance while eliminating cord wrap issues associated with external battery packs.

With the NexStar’s ergonomically designed hand control, the user is free to remove the hand control from its holder for remote use or leave it cradled for hands-free operation. With a touch of a button you can select the object catalog, change the slew speed, view fascinating information about an object, or simply know if a desired object is visible in the sky.

Features

• Proven NexStar computer control technology.
• High quality 90mm Maksutov-Cassegrain.
• Database allows telescope to locate over 4,000 celestial objects.
• Fully computerized Altazimuth mount.
• SkyAlign allows you to align on any three bright celestial objects, making for a fast and easy alignment process.
• Quick-release fork arm mount, optical tube and accessory tray for quick no tool set up.
• Flash upgrade-able hand control software and motor control units for downloading product updates over the Internet.
• Sturdy stainless steel tripod and accessory tray included.
• Internal battery compartment to prevent cord wrap during use.
• Includes CD-ROM The Sky Astronomy Software which provides education about the sky and printable sky maps.

About Celestron Maksutov-Cassegrain Telescopes

Celestron's Maksutov-Cassegrain telescopes are similar to Schmidt-Cassegrain models in regards to ease, durability, versatility, and minimal maintenance, but trade smaller fields of view for better resolution in planetary observation.

The Maksutov-Cassegrain is similar to the Schmidt-Cassegrain with essentially the same advantages and disadvantages. It uses a thick meniscus correcting lens with a strong curvature and a secondary mirror that is usually an aluminized spot on the corrector. The Maksutov secondary mirror is typically smaller than the Schmidt's which gives it slightly better resolution for planetary observing.

Advantages of Maksutov-Cassegrain Compared to Schmidt-Cassegrain

• Smaller secondary obstruction results in a slight increase in planetary detail and contrast
• Less expensive to manufacture
• Longer focal lengths resulting in higher magnifications for planetary viewing

Disadvantages of Maksutov-Cassegrain Compared to Schmidt-Cassegrain

• Slightly heavier because of the thick meniscus correcting lens
• Increased time to reach thermal stability in larger apertures over 90 mm
• Longer focal lengths resulting in smaller field of view