Most telescope users are familiar with the Schmidt-Cassegrain design, a short-tube catadioptric that is that is quite popular among astronomy and astrophotography buffs. But while most people are familiar with the name Schmidt, owing to the Schmidt camera, invented by Bernhard Schmidt, the origins of the Cassegrain part of the name eludes many. The Cassegrain
Most people think that getting into amateur astronomy and astrophotography means you’re getting into only one hobby. But if you’re aiming to be a serious observer and photographer of astronomical events, be prepared to immerse yourself in not one, but actually two hobbies.
Starting this January, the planet Venus will begin to appear gradually brighter in the western sky, right after sunset. Venus’ phase is changing from a roundish gibbous shape, into a half-moon shape, and then into a crescent shape, as seen in Figure 1. At first glance, this seems rather counter-intuitive—why would it get brighter, when