Castor & fresh Moon on March 30th

A clear night right at the start of my weekend and a darts match on the telly: goodbye, I’m off playing outside then! Out with the 8″ dobsonian! A setting and still young moon in the sky. Not the best of circumstances with some cirrus in the sky, but the seeing was allright and the 20mm eyepiece gave a decent view of the moon. With the sun so low over the moon’s surface a lot of details pop up you will not see a few days later. Nice! Out with the iPhone for a quick snap:

Moon at March 30, 2017

Next up was Betelgeuse, just to check the collimation. On low magnification it looked fine with six nice diffraction spikes (I have a 3-vane spider).

Afther that there was not much to see except the brighter stars. Right overhead were Castor and Pollux. Now, I did know that Castor is a six star system. But I didn’t really give Castor any TLC ..ever. Reading up on Castor right there next to the telescope I learnt that I should be able to make out the two bright O-stars. Also known as the A and B components of Castor. Also there should be a less bright C component visible. A and B are 7″ separated and C is 73″ away. Also, the C component spins round A+B but it is not known how long one trip takes but it is probably anywhere between 1,000 and 10,000 years. Information like that makes a simple star like Castor interesting! But the coolest part of Castor is that A, B and C are all double stars too! So in total that makes six stars all in one system! Through the telescope the view was very much like the one Jeremy Perez jotted down in 2008:

And this is an artist impression of the entire system:

Castor Star System

All in all an interesting couple of easy to find objects!

You may also like...