[OR] Guacamole Ridge March 14th

[Francesco Meschia]

Hello TACos,

On the night of March 14th I went to Guacamole to meet Daniel and Vignesh for some dark-sky time. Vignesh, as we already know, was there for his attempt (a very successful one) at a Messier Marathon, whereas both Daniel and I were imaging. We were later joined by Chris, who also had plans for a Messier Marathon, which ultimately didn’t happen because of a technical issue with his mount.

My imaging target for the night was a region of Camelopardalis that I had studied and had wanted to image for a long time. The centerpiece are two galaxies, NGC 2633 and NGC 2634. 2633 is a beautiful barred spiral galaxy, and 2634 is a lenticular galaxy showing signs of shells and arm-like projections, probably the result of the interaction with 2633. Both are located about 100 million light years from us. What makes this area remarkable, though, is not the presence of these two galaxies alone, but the fact that they are almost perfectly framed by two ribbons of galactic cirrus, or integrated flux nebula (IFN). Their distance is hard to know, but they’re certainly situated within the confines of our galaxy, so thousands of times closer than the galaxy pair.

Imaging this target presented several challenges. The galactic cirrus is very faint, with very low contrast with the background sky. If one looks at imagery from the igitized Sky Survey red plates, they show only a hint of the two structures. This was compounded by the fact that the region is circumpolar, but never high on the Northern horizon… and it was already a bit late in the season, crossing the meridian around 10:30pm. I needed a location with low light pollution to the North. Guacamole is decent in that regard, although not ideal due to Central Valley being just 30 miles away. 

Being limited to just one night, I managed to collect almost nine hours of data, which is close to the theoretical maximum. Yet the signal was really, really, weak and processing the data was a true challenge. I may even have had some terrestrial cirrus clouds get in the frame and diffuse the light of the brightest stars. Maybe, if I’m lucky, I will be able to collect more data next year and improve things. Anyway, the final (for now) image is attached – capture details and full-resolution version (you will want to look at it instead of the thumbnail here) can be found on Astrobin at https://app.astrobin.com/i/fn78rq. 

Francesco

[Ted Hauter]

Work of art there.

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[Francesco Meschia]

Thank you, Ted!

Francesco

On Mar 27, 2026, at 23:51, Ted Hauter <thgo...@gmail.com> wrote:

Work of art there.

On Fri, Mar 27, 2026, 4:41 PM Francesco Meschia <francesc...@gmail.com> wrote:

Hello TACos,

On the night of March 14th I went to Guacamole to meet Daniel and Vignesh for some dark-sky time. Vignesh, as we already know, was there for his attempt (a very successful one) at a Messier Marathon, whereas both Daniel and I were imaging. We were later joined by Chris, who also had plans for a Messier Marathon, which ultimately didn’t happen because of a technical issue with his mount.

My imaging target for the night was a region of Camelopardalis that I had studied and had wanted to image for a long time. The centerpiece are two galaxies, NGC 2633 and NGC 2634. 2633 is a beautiful barred spiral galaxy, and 2634 is a lenticular galaxy showing signs of shells and arm-like projections, probably the result of the interaction with 2633. Both are located about 100 million light years from us. What makes this area remarkable, though, is not the presence of these two galaxies alone, but the fact that they are almost perfectly framed by two ribbons of galactic cirrus, or integrated flux nebula (IFN). Their distance is hard to know, but they’re certainly situated within the confines of our galaxy, so thousands of times closer than the galaxy pair.

Imaging this target presented several challenges. The galactic cirrus is very faint, with very low contrast with the background sky. If one looks at imagery from the igitized Sky Survey red plates, they show only a hint of the two structures. This was compounded by the fact that the region is circumpolar, but never high on the Northern horizon… and it was already a bit late in the season, crossing the meridian around 10:30pm. I needed a location with low light pollution to the North. Guacamole is decent in that regard, although not ideal due to Central Valley being just 30 miles away. 

Being limited to just one night, I managed to collect almost nine hours of data, which is close to the theoretical maximum. Yet the signal was really, really, weak and processing the data was a true challenge. I may even have had some terrestrial cirrus clouds get in the frame and diffuse the light of the brightest stars. Maybe, if I’m lucky, I will be able to collect more data next year and improve things. Anyway, the final (for now) image is attached – capture details and full-resolution version (you will want to look at it instead of the thumbnail here) can be found on Astrobin at https://app.astrobin.com/i/fn78rq. 

Francesco

<3391CA8F-7130-42B6-BF05-4169CB63CAB3-NGC2633-12-sig.png>

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<3391CA8F-7130-42B6-BF05-4169CB63CAB3-NGC2633-12-sig.png><3391CA8F-7130-42B6-BF05-4169CB63CAB3-NGC2633-12-sig.png>

[Ted Hauter]

You're welcome 👍

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