June 17, 2019

Event of the Week: A New England Occultation.

Lunar occultations are always cool events; now you see a star or planet, now you don’t. The way they “wink in” and “wink out” with an improbable abruptness reminds us of the colossal velocity of the Moon about our planet. But beyond being just plain cool, they also still have scientific value; close double stars have been discovered this way, as they “wink out” in a step wise fashion. If enough observers are placed along the graze line, an accurate profile of the limb of the Moon can even be ascertained.

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17.08.09: A Ramadan Moon.

Slender New crescent Moons are always a fun and interesting challenge to spot…but this week’s crescent Moon is special. For the astronomy challenge of the week, I give you a Ramadan Moon. The Muslim calendar is one of several that are lunar based, meaning that it follows a cycle of complete phases of the Moon through one synodic month, which is 29 days 12 hours 44 minutes and 3 seconds long, respectively. This means that any given lunar calendar falls about 10-12 days per year out of sync with the Gregorian solar based one. Ramadan, (“or Ramazan,” as its known in Turkey) begins at sunset with the sighting of the Hilal or crescent New Moon and is the ninth month of the Islamic calendar.

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Astro-Event of the Week: 1st-7th December, 2008: A dusk tri-conjunction.

This week’s astro-event requires absolutely no gear to observe, just a clear sky. Look westward into the dusk, just after sunset the evening of Monday, December 1st. Venus and Jupiter will be joined by a thin, waxing crescent Moon for a spectacular tri-conjunction . [Read more...]