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Winter Solstice is worth observing

The summer and winter solstices mark a special time in our calendar. When the sun is over the Tropic of Capricorn this is the peak of summer in the southern hemisphere, the longest day of the year and it predictably occurs on 21 December. When the sun is over the Tropic of Cancer, this signals the shortest day of the year, and, predictably, it is always on 21 June. On this day the southern hemisphere is leaning away from the Sun at its greatest angle. Use this link for an informative and amusing series of diagrams by Dr Nick Lomb illustrating these phenomena. Building monuments which align with the solstices has been a challenge for architects, engineers and astronomers for centuries. One of

Our excellent telescope viewing night

It was a balmy evening on Monday 1 May and thirty-one attendees, including nineteen members of our astronomy group, had a very successful night of telescope viewing at Sydney Observatory. Many Sydney City Skywatcher members brought their own telescopes or astronomy set-ups, but we all assisted in setting up, had many opportunities to view through different types of telescopes and binoculars, and there was much discussion about what we were viewing and the equipment. Robert (pictured above) demonstrated his new and highly portable celestron. Adriano demonstrated his large Skywatcher motorised Dobsonian and several attendees took smart-phone photographs through the eyepiece. You can see Vlad's

Solar Observations for April 2017

SUNSPOTS AND SOLAR FLARES A solar flare is an intense burst of radiation coming from the release of magnetic energy associated with sunspots. Flares are our solar system's largest explosive events. They are seen as bright areas on the sun and last from mere minutes to several hours.Scientists classify solar flares according to their x-ray brightness. There are 3 categories: X-, M- and C-class. X-class flares are the largest of these events. M-class flares are medium-sized; they can cause brief radio blackouts that affect Earth's polar regions. Compared to X- and M-class, C-class flares are small with few noticeable consequences on Earth (NASA https://www.nasa.gov/multimedia/imagegallery/imag

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