Exploring the Suffolk Virginia Night Sky – Astronomy, Astrophotography, Telescopes, EAA – Planets and Stars and Nebula and Galaxies – Looking, Learning, Sharing… Let's see what we can see…
The forecast for the night was not great, but it was fairly clear just before dark. The temperature was in the mid-70s and the humidity was not quite as bad as it has been. I uncovered the scope hoping to capture a bit of light. The target for the night was NGC 4435 and NGC 4438, the Eyes Galaxies. I also wanted to grab a few frames of the recurring nova T CrB. Some nights everything goes great… others not so much, this was a not so much night.
I had issues with cooling the sensor. It kept frosting up. I could not get it down to -10 C without a bunch of frost. I did not realize it right away and ended up shooting a couple runs of flats, which I later found out were no good. Best I could get the cooler to was -5 C.
The first few autofocus runs failed as well. I ended up adjusting the Autofocus step size (Options -> Autofocus) from 25 to 30 and this seemed to fix it.
Polar alignment went pretty quick using NINA’s Three Point Polar Alignment. I was able to get it dialed in with in 10 arc seconds in both azimuth and altitude. So we can call that a win for the night.
Finally… clouds. It was mostly clear, but clouds started rolling in a little after 11 PM. I started losing my guide star due to the clouds around 11:15 PM and by 11:30 PM the sky was pretty much full of clouds.
NGC 4435 and NGC 4438, the Eyes Galaxies, are the SkyWatcher USA TOTM for June 2024. I had hoped to collect 3 hours of light from the Eyes, but only ended up with an hour and a half. I did add this capture to the TOTM page. I had also hoped to get at least 30 minutes on the recurring nova T CrB, but ended up with only a single 300 second frame before it was completely obscured by clouds.
I wanted to capture a lot more light, but I ended up calling it a night and parking the scope a little after 11:30 PM. I just did not feel like fighting clouds. A bit frustrated but I guess at least I did get some data.
NGC 4435 and NGC 4438, Eyes Galaxies, part of Markarian’s Chain in the constellation of Virgo. This is a stack of 18 x 300 second exposures, 121 gain, 30 offset, bin 2×2. Stacked in Siril. Cropped, Background Extraction, and Denoising in GraXpert. Color calibrated, histogram stretched, and color saturation adjusted in Siril.
The pair of galaxies, NGC 4435 and NGC 4438, are about 52 million light years from Earth. The Eyes are in the middle and Markarian’s Chain runs through the FOV from top left to bottom right. M86 is the large galaxy at the bottom of the FOV. You can see a bit of the dark cloudy detail in the right side “eye” (NGC 4438) just under the bright center of the galaxy. There is little face on spiral galaxy in the far right center which I think is really neat. I will try to get some more time on this, and hopefully get some flats to clean it up a bit. Lot of interesting little galaxies in this stack. See the annotated image on Astrometry.net.
Then one single 300 second frame of T Crb aka V*T CrB aka T Coronae Borealis aka the Blaze Star a recurrent nova in the constellation Corona Borealis. T CrB is expected to have a outburst sometime between now and September 2024. I opened this single frame in Siril and did remove green noise, background extraction, color calibration, histogram stretch, deconvolution, and color saturation to get the image below.
T CrB is in center of the frame. I had hoped to more light from it, but this will be the start for comparison over the next few months. Will keep watching it. I plan to capture some light from it, even if it is a single exposure, during every session.
Not the best night out, but not the worst. Hoping for clearer skies soon…
