Cepheid & RR Lyrae Stars: Cosmic Distance Yardsticks
Learn how Cepheid and RR Lyrae variables power the cosmic distance ladder via the period–luminosity relation, from Leavitt’s law to today’s H0 tension.

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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Learn how Cepheid and RR Lyrae variables power the cosmic distance ladder via the period–luminosity relation, from Leavitt’s law to today’s H0 tension.
Master Ha, OIII, and SII imaging in bright cities. Gear, filters, exposure, calibration, and processing workflows for stunning narrowband astrophotography.

You want to stargaze and set up your telescope and mount it in your backyard. But then you find that you can’t really see much. Light pollution could be the culprit!  What is light pollution? Light pollution refers to artificial lighting in your environment that can cause the sky to be brighter, and this essentially