Celestron NexStar HC manual Observing the Sun, Observing Deep Sky Objects, Seeing Conditions

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Observing the Sun

Although overlooked by many amateur astronomers, solar observation is both rewarding and fun. However, because the Sun is so bright, special precautions must be taken when observing our star so as not to damage your eyes or your telescope.

Never project an image of the Sun through the telescope. Because of the folded optical design, tremendous heat build-up will result inside the optical tube. This can damage the telescope and/or any accessories attached to the telescope.

For safe solar viewing, use a solar filter that reduces the intensity of the Sun's light, making it safe to view. With a filter you can see sunspots as they move across the solar disk and faculae, which are bright patches seen near the Sun's edge.

Solar Observing Hints

•The best time to observe the Sun is in the early morning or late afternoon when the air is cooler.

•To center the Sun without looking into the eyepiece, watch the shadow of the telescope tube until it forms a circular shadow.

•To ensure accurate tracking, be sure to select solar tracking rate.

Observing Deep Sky Objects

Deep-sky objects are simply those objects outside the boundaries of our solar system. They include star clusters, planetary nebulae, diffuse nebulae, double stars and other galaxies outside our own Milky Way. Most deep-sky objects have a large angular size. Therefore, low-to-moderate power is all you need to see them. Visually, they are too faint to reveal any of the color seen in long exposure photographs. Instead, they appear black and white. And, because of their low surface brightness, they should be observed from a dark-sky location. Light pollution around large urban areas washes out most nebulae making them difficult, if not impossible, to observe. Light Pollution Reduction filters help reduce the background sky brightness, thus increasing contrast.

Seeing Conditions

Viewing conditions affect what you can see through your telescope during an observing session. Conditions include transparency, sky illumination, and seeing. Understanding viewing conditions and the effect they have on observing will help you get the most out of your telescope.

Transparency

Transparency is the clarity of the atmosphere which is affected by clouds, moisture, and other airborne particles. Thick cumulus clouds are completely opaque while cirrus can be thin, allowing the light from the brightest stars through. Hazy skies absorb more light than clear skies making fainter objects harder to see and reducing contrast on brighter objects. Aerosols ejected into the upper atmosphere from volcanic eruptions also affect transparency. Ideal conditions are when the night sky is inky black.

Sky Illumination

General sky brightening caused by the Moon, aurorae, natural airglow, and light pollution greatly affect transparency. While not a problem for the brighter stars and planets, bright skies reduce the contrast of extended nebulae making them difficult, if not impossible, to see. To maximize your observing, limit deep sky viewing to moonless nights far from the light polluted skies found around major urban areas. LPR filters enhance deep sky viewing from light polluted areas by blocking unwanted light while transmitting light from certain deep sky objects. You can, on the other hand, observe planets and stars from light polluted areas or when the Moon is out.

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Contents Page Celestial Coordinate System Telescope Maintenance Some of the many standard features of the NexStar include Flip Mirror Focuser Knob Direction Buttons Page Assembling the NexStar Powering the NexStarEyepiece Hand ControlEyepieceStarPointer Diagonal Flip Mirror Control Focuser KnobStar Pointer Finderscope with Mounting Bracket Star Pointer FinderscopePage Hand Control Rate Button Utility FeaturesGuideStar Software NexStar Hand Control Hand Control Operation Alignment ProcedureEnter Selecting an Object Object CatalogSlewing to an Object More InformationTour Mode Direction ButtonsObserving Tip Setup Procedures User Objects Helpful Utility FeaturesNexStar Ready Image Orientation Focusing Calculating MagnificationDetermining Field of View General Observing Hints Celestial sphere seen from the outside showing R.A. and DEC Celestial Coordinate SystemMotion of the Stars Definition Polar Alignment with optional WedgeAttaching a Camera to the NexStar Photography with the NexStarFinding the North Celestial Pole Observing the Planets Observing the MoonObserving Deep Sky Objects Observing the SunSeeing Conditions TransparencySeeing Care and Cleaning of the Optics Super Modified Achromatic SMA Eyepieces 11/4 Page Page Appendix a Technical Specifications Appendix B Glossary of Terms Page Page Appendix C Maps of Time Zones Page Page Page Page Page Page Page Celestron ONE Year Warranty Page Addendum to Nexstar Telescope Manual

NexStar HC specifications

The Celestron NexStar Hand Controller (HC) is an advanced control unit designed to enhance the astronomical observation experience for both novice and experienced stargazers. This innovative device is an integral part of the NexStar telescope series and offers a range of features that simplify the process of locating celestial objects.

One of the main features of the NexStar HC is its user-friendly interface. The controller is equipped with a large, illuminated LCD screen that displays essential information clearly, even in low-light conditions. The layout is intuitive, allowing users to quickly familiarize themselves with its functions. The keypad includes dedicated buttons for common tasks, making it easy to navigate the expansive database of celestial objects.

The NexStar HC boasts an impressive database containing over 40,000 celestial objects, making it a powerful tool for astrophotography and observational astronomy. Users can access planets, stars, galaxies, and nebulae at the touch of a button. The built-in database allows for precise and efficient locating of objects, significantly reducing the time spent searching the night sky.

One of the standout technologies featured in the NexStar Hand Controller is the GoTo functionality. This advanced tracking technology enables the telescope to automatically locate and track celestial objects with high precision. By entering the desired object into the controller, users can allow the telescope to autonomously adjust its position, providing a hassle-free experience.

Additionally, the NexStar HC supports various alignment methods, including SkyAlign, AutoAlign, and One-Star Align. These alignment techniques assist in calibrating the telescope for optimal tracking and positioning. The SkyAlign method, in particular, allows users to point the telescope at any three bright stars, and the HC will calculate the telescope's location in relation to those stars, making alignment accessible even for beginners.

The NexStar Hand Controller is also compatible with Celestron’s StarSense technology, enabling automatic alignment using a smartphone. This feature allows users to refine their observations seamlessly and provides a modern twist to traditional stargazing methods.

Other notable characteristics include programmable go-to tracking speeds and the ability to save user-defined locations. The controller’s ergonomic design ensures comfort during long observing sessions, while the robust build quality guarantees durability.

In summary, the Celestron NexStar Hand Controller combines a wealth of features and cutting-edge technologies to enhance the stargazing experience. Its user-friendly interface, extensive database, versatile alignment methods, and compatibility with advanced tracking systems make it an indispensable tool for anyone looking to explore the wonders of the night sky.
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