Dodecahedron Books: Gemini (Castor and Pollux), Photographed with an iPad

Tuesday 1 December 2015

Gemini (Castor and Pollux), Photographed with an iPad

From a bright city sky (or as captured with an iPad), you can’t make out all that many stars in the constellation Gemini. But, the two main stars, the “twins” of ancient mythology are easy to make out, as they are magnitude 1 stars (e.g. Castor=1.5, Pollus=1.0, both very bright). Alhena is also quite bright (mag=1.9) and easy to find, approximately on a line from Pollux to Betelgeuse, the very bright shoulder star of Orion (magnitude 0.5).

Straight down from Castor and Pollux is the extremely bright star Sirius (magnitude -1.5). In a northern sky it is always quite low on the horizon, so it is usually rather twinkly and can have some interesting refractive (colour) effects.

Here’s a close-up map of the same stars, from Sky and Telescope. Obviously most of the stars are far to dim to be seen in the city, and the iPad only picks up the brighter stars. But now you can find Castor and Pollux, “the twins”, and that’s pretty neat.

In Greek mythology, Pollux was the son of Zeus. To get the full story, read the Wiki article.

https://en.wikipedia.org/wiki/Castor_and_Pollux

“Leda and the Swan” is a famous poem by Yeats, related to Pollux. Warning: Zeus was a pretty crazy God.

https://www.poets.org/poetsorg/poem/leda-and-swan

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And here’s the “call to action” that all good social media is supposed to contain (especially content rich blogs :). If you like stories set in deep space, or on distant worlds with alien cultures, you might enjoy the Kati of Terra series or the Witches’ Stones series, by Helena Puumala, published by Dodecahedron Books.

Kati of Terra Book 1: Escape from the Drowned Planet