It was such dreadful weather today that I was a bit surprised to see the Moon (ideally placed!) from the bedroom window tonight. Its phase was also close to that in “Moonwatch” in May’s Sky at Night magazine. So, here is another one of those images replicating the one in the magazine. It would seem that the lunar libration is such that tonight’s image is a bit more foreshortened than the one in the magazine. Also, the magazine image was taken after full moon, mine were taken before full moon. Therefore the shadows are reversed.
Below is my original image followed by one cropped to approximately replicate the magazine one.
Trawling through my archives, I found this one from last year, admittedly from a much smaller original image. ( https://roslistonastronomy.uk/two-more-moonshots-21-22-day-moon ). The illumination is much closer to the pic in the magazine, and the difference is quite striking. You can now see the ray system around Byrgius A, which simply is invisible on the image from this year!
Following on from Ed’s talk earlier in the year about what can be achieved with a smartphone this is well with a look. I suspect the dark skies had more than a little to do with it, but still very impressive.
So after a month of absolutely nothing doing at all, along- like buses- came several clear nights. Bit tricky to fit around work and family commitments, but at last had the chance to get out and really try out the new Dob. Despite a lot of turtle wax it’s still a little bit sticky, especially on the azimuth, but otherwise it now feels to be working really well.
On the 19th it was a bit hazy- I’ve started using M51 as a gauge of sky quality, and on this occasion the 2 cores were visible, but not the spiral arms. Nonetheless I pressed on to go Galaxy hunting around Virgo. I’m using Sky Safari to help me with this and find that for the most part I can manage to star hop by using overlay tool and I was able to explore the region around Vindemiatrix picking up 6 new galaxies for me. For the sake of comparison I got the 8 inch Dob out as well to see if I could achieve the same, but I simply couldn’t find them. My back garden certainly has a fair bit of light pollution, and it seems the extra aperture enables me to find things which I otherwise wouldn’t see.
On Thursday and Sunday I also had some time later on with slightly more mixed results. I spent some time on Leo- the M66, M65, NGC3628 triplet was easily found and a nice sight, but I struggled to get to M96/95/105 and really want to have another go at that. More satisfyingly, the Beehive looked wonderful, M92 was great and M13 was stunning- the heart of it was like a shimmering circle of sequins. Gorgeous. The best was yet to come- late on, Jupiter appeared over the rooftops. Unfortunately for me I’m looking through the light pollution and rising heat of Burton in that direction, but even with it dancing in the haze it was a wonderful sight, the bands strikingly clear and colourful. At times I could see the Great Red Spot.
Whilst doing this I had the 5 inch newt set up and pointing at Markarian’s Chain. I hadn’t managed to hop to this with the Dob, and trying to frame it was a challenge (I lost quite a bit of time trying), but I’m quite pleased with the result. It’s 15 4 minute subs, 5 darks and some flats & bias. I can find 15 galaxies in this shot which blows my mind…
The clear skies have been a long time coming but it’s been worth the wait!
All of the following use Zeiss condenser NA 1.4 and low NA Leitz 25x objective (NA 0.22).
The following photo is a BRIGHT FIELD image of part of the slide – the bacteria are just visible as the blue/black mottling top right/and at bottom left:
The following picture is of the same field of field of view with same condenser and objective but adding in COL annulus – I don’t think there is a deep sky astronomy filter that works quite as well as this!
The following photo uses a COL filter with smaller hole for light to pass through – do you think there is a meaningful difference between the two?
I think there a difference – the bacteria stand out a bit more BUT so do the larger hill-like mounds in the background – these are due to dust on the slide or optics.
The following is a dark field photo (changed to greyscale in GIMP2) – again the contaminants stand out as well as the bacteria which is a real nuisance, although the bacteria are easily seen – same condenser and objective as above:
Here is this morning’s image of spot 2706, together with the “chromosphere sequence” for the spot as suggested in my post the other day. (https://roslistonastronomy.uk/layers-in-the-solar-chromosphere)
Here is a movie as you travel down through the chromosphere: