Sky Coordinates and Timekeeping: RA/Dec, LST, Alt‑Az
Master celestial coordinates and timekeeping. Convert RA/Dec to Alt‑Az, compute local sidereal time, handle precession, refraction, and plan precise observations.

Guides to help with your Stargazing Adventure

Information on Galaxies, Stars, Constellations, Planets, Moons, Comets and Asteroids
Listen to Bernard Miller describe his journey into AstroPhotography and detail how he captured this stunning image of the Sculptor Galaxy.
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Drew Evans talks about his passion for astrophotography, the equipment used and tips for post processing image data.
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Hear D.j Van Bourgondien as he talks about using his Celestron EdgeHD 8″ telescope to capture this image of the Fireworks Galaxy
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Below are a selection of our Articles, to find more click on one of the sections above, or use the Menu at the top of the page.
Master celestial coordinates and timekeeping. Convert RA/Dec to Alt‑Az, compute local sidereal time, handle precession, refraction, and plan precise observations.
Discover the Pleiades (M45): when and where to see it, its distance, age, stellar science, global myths, and tips for observing and astrophotography.
Choose, set up, and collimate an 8-inch Dobsonian. Eyepieces, accessories, portability, and observing tips for beginners and seasoned stargazers.