12/24/2022
Location: home,
Bortle 6.5
Equipment: Celestron 8”
SCT and Stellarvue 102ED on iOptron AZMP mount; EPs: Pentax XWs set.
Our son with girlfriend supposed to spend the Christmas with us, but she caught a bug and the plans were canceled at the very last moment. On a positive side we had a warm spell with clear skies and dry air. Thus, for the first time in my life I was observing on the Christmas Eve and loved it!
For 24 years we have spent Christmas Eve feeding kids, getting them to bed and pooling and wrapping the presents. We may miss it eventually, but not this time. Slow relaxing holiday was a welcome change.
I have set the scopes in the backyard around 16:00, had a nice dinner with my wife (between the two of us it will take a while to finish all the holiday food) and stepped out around 18:30. The sky was of better quality. AZMP mount has used Jupiter for the alignment, so it was my first target for the evening.
JJUPITER
The seeing was good and Jupiter view in 8”
SCT nice and detailed. All four major belts were well defined as well as North and South Polar regions. Multiple festoons were resolved in the North and South Equatorial Belts and there was also a dark oval storm in the North Equatorial Belt. What immediately caught my attention is how sharp and well defined were light zones between the belts. They were of bright white color, at high contrast with shaded polar regions and dark belts. While the view was very detailed, it was monochrome, no hint of color. I have tried Pentax XW 20mm (102x), 14mm (145x) and 10mm (203x) in 8”
SCT, and all delivered nice views.
I thought the views in
SCT were great (and they were) but when I have switched to SV102ED frac with XW 5mm (143x) and 3.5mm (204x) I was surprised how sharper and higher contrast the image was. I see often on forums people bushing SCTs, but I can tell that mine 8” is very nicely configured and performs well to the specs. It is just in the range of powers I typically used for planets (100-200x) larger
aperture of the
SCT is disadvantageous, since it just intensifies Jupiter’s glare, and combined with relatively large central obstruction produces somewhat washed-out views.
ASTEROIDS
I love hunting asteroids. Of cause they look just like faint stars (hence the name), but to me seeing a small rock hundreds of millions miles away is mind-blowing. They also offer a good challenge. Depending on the position in the orbit their apparent magnitude can change significantly. So, one need to wait for a window of opportunity. Even then most of them are faint and require good quality sky, sharp optics, and trained eye to positively ID in the star field. SkySafari Pro
app is the best tool since it accurately tracks positions of thousands of asteroids and shows all stars down to mag 15. I typically wait 2-3 months between asteroid sessions, which gives enough time for a new batch to move in. The table below sums up my haul for the evening. For asteroids hunting 8"
SCT has provided definite advantage over 4" ED frac and even 7" Mak I have used in the past. Here like with
DSOs aperture is the queen.
MARS
Can’t finish the session without looking at Mars. Was not happy with the view produced by 8”
SCT – too much glare. SV102ED has produced much sharper and higher contrast image. I have played with filters and #23 Red filter and Baader Contrast Booster filter have highlighted low
albedo features a bit better compared to no-filters. Looking at Sky & Telescope Mars Profiler I have resolved Mare Acidalium and Arcadia in the Northern hemisphere, and Mare Erythraeum with Aurorae Sinus and Margaritifer Sinus in the Southern hemisphere.
