An ISS transit over the moon, and supernova SN 2014J again

Yesterday evening 9 February near 23:38:30 local time (22:38:30 UT) the International Space Station (ISS) made a transit in front of the moon, as seen from Leiden.

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While the pass itself was good (the transit occured at 45 degrees elevation),  atmospheric conditions were far from perfect. The evening started clear, but as I was setting up the Celestron C6 fields of clouds came in. There was a strong wind rocking the telescope tube.While focussing on the moon, I noted that the seeing was abysmal: the lunar disc trembled and shivered from atmospheric turbulence, and rolling waves went over it, as if it was reflected on the surface of water. Test shots showed a much more blurred moon image, even at 1/400s, than I am used to with this instrument.

The final minutes were tense. A field of clouds came in and covered the moon minutes before the transit would start. Near the horizon I could see even thicker clouds. In the last two minutes before the transit, a gap in the scattered clouds appeared. At the moment supreme, 22:38:29 UT, the moon was right in this clear gap!

Three images out of a rapid burst series started a few seconds before the calculated transit time captured the ISS, as a ghostly dark bat in front of the moon. Nothwithstanding the bad seeing, wind and perhaps a slightly too long exposure time (1/400 second), structure is visible: the ISS solar panels are well visible for example.

The ISS was at a distance of 575 km over the British channel during the transit,  with an apparent size near 48". The transit took less than 1 second. As the ISS was not illuminated by the sun, it was visible as a dark silhouet (see the image above).


M82 and supernova SN 2014J

A few days earlier, in the evening of February 4, the sky was clear and I photographed galaxy M82 with supernova SN 2014J again. The wide field image below, a stack of 34 x 15 seconds at ISO 2000 also shows nearby spiral galaxy M81. The arrow points to the supernova:

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OT - Supernova SN 2014J in Messier 82

This is off-topic as it is not satellite related: but cool enough to warrant a post.

As about every astronomy afficionado will know by now, a Type Ia supernova was discovered in the relatively nearby bright galaxy M82 in Ursa Major (the Big Dipper) on January 21, 2014. The supernova, SN 2014J, was discovered from London (!), UK, by astronomy students of University College London during a teaching session. Being relatively near, it is relatively bright: about mag. +11.5 upon discovery, it currently is peaking at mag. +10.5.

Weather was very bad here in the Netherlands over the past two weeks: clouds, rainshowers, and strong haze (especially in the coastal region where I live). As my frustration grew, I scheduled a 'remote' image session using the 0.81-meter Ritchey-Chretien (the same telescope I frequently use for my asteroid observations) of Mt. Lemon Sky Center (MPC G84) in Arizona, USA. Below is a single 30 second exposure which I made with this telescope on January 29. The arrow points to the supernova:

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Of course I was still hoping for clear skies in the Netherlands, so I could try to observe and image the supernova with my own Celestron C6 Schmidt-Cassegrain. As day after day of bad weather passed, my frustration grew. I was pretty miffed when a few days ago an evening started clear, but haze came in while I was setting up the telescope. Grrrrrrrrr!!!!!!

Yesterday evening my luck finally changed: a nice clear sky at last! I set up the Celestron C6 and after some quick aligning, pointed it to M82 and M81 in the Big Dipper using a 38x magnification.

Both galaxies were easy to see, even from the middle of Leiden. And there it was: the cigar shape of M82 had a tiny but well visible star somewhat off-set from the center: supernova SN 2014J!

This was the second time I visually observed a bright supernova in another galaxy: almost exactly 15 years ago, in February 1989, I had seen supernova SN 1989B in M66 with my old 4.5" Newton.

After a satisfying visual look, I attached the Canon EOS 60D to the telescope and took a number of 10-second images (as my telescope had not been entirely well polar-aligned, longer exposures were not possible). Below is a stack (digital summary) of  33 images of 10 second exposure each, taken with my Celestron C6 15-cm Schmidt-Cassegrain (with F6.3 focal reducer) in the evening of February 1 near 22:55 UT:

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