Capturing the Rho Ophiuchi Cloud Complex was like my own personal quest to find the 6 Infinity Stones (which ironically share some of the same colors as many of the objects in this image), and I’ve have been completely obsessed with capturing it. The journey started back in 2020 and ended on the 5th of October 2021. I originally finished collecting data on this object at the end of August 2020, but I decided this year to add Hydrogen-alpha (Ha) and, in the process, like any astrophotographer, I decided the image needed more data, lol. I always envisioned capturing an additional celestial object passing in front of the Cloud Complex, but at the time I had no idea when such an event would occur. When I began collecting Ha in April of this year I discovery that C/2020 T2 Palomar would be passing in front the Complex in October 2021. To be honest, I thought it would be pretty much impossible to capture the comet passing in front of Rho Ophiuchi. With the limited time that Rho Ophiuchi would be in the sky at this time of year combined with the very short window to capture the fading comet, I knew I’d have to get extremely luckily. Not to mention I had no idea what the weather would be like when I was planning this back in April, or even if it would come out the way I envisioned it. But sometimes you get a win in this hobby, the conditions and timing were right, and I was able to capture the comet before it passed out of the Cloud Complex completely.  

Thanks for viewing and Clear Skies everyone!  

Info about the Rho Ophiuchi Cloud Complex and comet:  
Located in the constellation Scorpius, the large multicoloured Rho Ophiuchi Cloud Complex, contains several objects including reflection (blue), emission (red) and dark nebulae as well as a few globular star clusters. The bright shining yellow star Antares (lower left) is about 550 light-years away. While the globular cluster (M4) at the bottom right top is one of the nearest globular clusters to Earth at 7,000 light-years away. The smaller globular cluster between Antares and M4, which is NGC 6144 is nearly 33,000 light-years away!  
The comet C/2020 T2 Palomar, was recently discovered by the Palomar/Zwicky Transit Facility survey on the night of October 7th, 2020. This celestial object won’t return to the inner solar system for over another five millennia. The comet topped out at +9th magnitude in August and is now rapidly fading low in the dusk sky.  

Tech info:
This image is a 4-panel mosaic. Individual (Ha, L, R, G & B) channels were stacked in AstroPixel Processor and processed in PixInsight, with finishing touches applied in Photoshop. Several telescopes and cameras were used to capture this image. Information regarding filters and exposures can be found below:  

Filters and Exposures (Rho Ophiuchi Cloud Complex) (For 4-panels) 

RGB Subs = 180sec; Bin 2x2 
Luminance (L) Subs = 300sec & 600sec (about 1hr per panel for 600sec subs) Bin 1x1 
Ha Subs = 600 sec; Bin 1x1 

L =   5.9 hrs 
Ha = 7.3 hrs 
R = 2.7 hrs 
G = 2.7 hrs 
B = 2.45 hrs 

Filters and Exposures (comet C/2020 T2 Palomar)  

RGB Subs = 180sec; Bin 2x2 
Luminance (L) Subs = 180sec; Bin 1x1 

L = 9 mins 
R = 6 mins 
G = 6 mins 
B = 6 mins 

Total Integration Time: 21.5 hrs