Comet Lovejoy – February 17th, 2015

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One more imaging run with comet Q2 Lovejoy. Again under the darker skies of the Comana Woods, with Claudiu and his 60mm hand-held refractor. I’m mentioning his instrument because on this occasion we did a very small Messier tour at 15x, and this due to two hours of rather dark skies, before some fog rolled over us.

The first object I’ve started to shoot was the comet itself.

As in most of my latest imaging sessions, the main instrument used was the 65mm TS APO Refractor (F/6.5) coupled with the Canon 550D DSLR at ISO3200. This time no guiding via PHD was done, only the NEQ6-mount’s 3-Star alignment method was used. 12 frames each a 4 minute exposure were stacked. The tail is still there but it’s a bit dimmer, while the coma is somehow smaller compared to just a few nights ago. These might be the last days to catch the comet’s tail visually in telescopes, and easy enough in photographs.

The comet was very difficult to spot with the naked eye, despite the rather good conditions. I think a good visual magnitude estimation would be around +5.5.

First image:

Q2 Febr 17And a sequence showing again the “normal” image, but also two comparison images processed without stars, depicting the details of the tail:

Q2 Febr 17 three viewsWhile we were observing some Deep-Sky objects with Claudiu’s small refractor, we found the two open star clusters near Sirius, namely Messier 46 and 47. Looking through the refractor, M 47 was easily the brightest, while M 46 looked like a ghostly patch of light very close to M 47, with some stars resolved with adverted vision.

The following image is a 14-frame stack, each a 2 minute exposure. There are other objects in the same field, like planetary nebula NGC4238 in M 47 (the greenish round disc) and a much smaller open cluster just between M 46 and M 47, with the NGC catalog number 2425.

First, a large version of the image:

M 46 47 largeAnd a reduced (Full HD) version:

M46 47 wallTo identify some of the objects in the field:

IDENTOur last celestial target of the session was planet Jupiter through a 127mm Maksutov telescope. It was this scope’s first light, and, of course, the seeing conditions were awful. The final image is an RGB one, with 800 frames acquired for each channel. The camera was a DMK 21 with Baader CCD RGB filters. The F/D ratio was around 25. The Great Red Spot is very easily discernable, as are some inner details.


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