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May 2010

Disappearance of TYC 1357-02074-1 on 17 May 2010

Congratulations to new Section member John Jarman, from Cumbria, who successfully managed to observe and time the disappearance of the magnitude +6.4 star TYC 1357-02074-1.

John Jarman – Cumbria.

Got this one! The sky was clear and the seeing good. Time of disappearance 22:20:13.21 UT. I did get a sense of the Moon’s motion in the last few minutes. The target star was perfectly stationary in the centre of the field of view and the Moon’s limb crawled across – awesome. However, it was touch and go as high cloud covered the moon 15 minutes later.

Jeff Stevens – Stoke-on-Trent.

I observed from 21:15 UT to 22:50 UT on Monday 17th May 2010. Despite the moderate seeing conditions, with slight undulations, there were moments of crisp views of the lunar disk, seen through a William Optics refractor at 31x magnification. The low magnification view of the Moon provided a wealth of minute detail to see – the craters Atlas and Hercules were particularly prominent.

The dark lunar limb was very clearly visible, due to the Earthshine effect, presenting a mottled grey disk against a jet black background sky in the eyepiece of the telescope. During the last few minutes I kept the bright crescent out of view, so that I could concentrate on that single point of light, soon to be extinguished, and there was a real sense of the motion of the Moon. But then those last few seconds seem the longest, when it appears the gap between star and limb is non-existent, and then finally the star blinked out in an instant. My timing on this occasion caught the star disappearing at 22:22:32.35 UT.

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