Mars in the morning of September 6th

For the night of September 5th to 6th, predictions were not that good: clouds passing over, some jetstream that started increasing. I had the scope outside and collimated using the tri-Bahtinov on a star of the Pegasus square in the evening, it then cooled all night .

After a few hours of sleep, I woke up to see that Mars was high in the sky looking very bright & pretty next to the Moon. It was just freed up of a cloud band that barely cleared the beautiful duo.

When I started imaging, it was obvious that the seeing was fairly good. The larger albedo structures on the planet were steadily visible on the laptop screen.

The first series prooved to be the best. it was composed of

  • IR 120s @62FPS 7509 frames CM 207°
  • B 120s @22 FPS 2730 frames CM 207.1°
  • G 120s @40 FPS 4831 frames CM 206.6°
  • R 120s @76 FPS 9188 frames CM 206.1°

with a classic C11, a unbranded 2″ barlow, a Starlight XPRESS 1 1/4″ 7-position automated filter wheel with Baader filters, an Esatto 2″ focusser and the ASI290MM

Altitude 45°
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Mars (derotated)

Building on the excellent albedo features of the IR image dd. 29/8/2020, and using WinJupos and two additional Green and Blue images (taken a few minutes before the IR), it was possible to combine a color image. However, some more experience is required as it generated some artefacts on the dark terminator, which I needed to cosmetically remove. it seemed as there was an overrun of the red image. See also:

M109 again, with the C11. With the ASI183mm

This is such a nice galaxy! Spiral arms and a central bar, beautiful! After the attempt to image it th elast nights with the C11 & Nikon, again a few nights (nights are short!!) now with the ASI183mm.

Th epixels are a bit small, and the C11 ‘s output is oversampled. In that respect the Nikon’s larger pixels (5µ) make more sense. However, this really worked out more acceptable then the previous attempts.

Using SIMBAD, you can identify some of the smallest and faintest patches in this image. SDSS J115703.88+532414.6 was about the faintest one with a listed green band magnitude of 20,893! The image itself measure 20′ x13′ end has a resolution of 0,6″ per pixel. Seeing was rather bad these nights, with nortwest sea air blowing over. Very clear however, with SQM 20,40 on average.

The C11 was guided with a 8×50 finderscope, using an ASI290MM. Autofocus was done using an Esatto 2″ focuser.

M109 3,8 hours LRGB C11 ASI183 Meldert May 2020
Searching the limiting magnitude
Astrometry from