NGC 7331 & Supernova SN2025rbc

This has been a fun image to work on. The center piece is the galaxy NGC 7331. I saw NGC 7331 visually a few times with my 12” Dobsonian. It is a challenging and faint target. Best view was at Glacier Point in Yosemite, where I was able to pick up some of the spiral structure and 4 of the dimmer nearby galaxies. This image has captured so much more – a supernova, a galaxy zoo (at least 39 galaxies that I could find), some galaxies that do not have published redshift data so their distance is uncertain, a historical NGC object that was incorrectly marked as a potential galaxy in the 19th century but is now known to be a double-star and one galaxy located 2.5 billion light-years away, making it the oldest photons I have ever captured.
The supernova near the center of the galaxy was detected on July 14, 2025 and is still quite bright. It is a supernova type 1a, when a white dwarf exceeds the mass of 1.38 solar masses (AKA the Chandra limit) and the entire star instantly collapses and detonates and for a while was as bright as the entire galaxy core. NGC 7338 was erroneously catalogued as a galaxy, we now know it is a double star, but it has been kept in the catalog to preserve the historical record. Below I have listed all the galaxies that I have been able to identify and their distances. The record is Galaxy PGC 3088708 with an estimated distance of 2.2 to 2.5 billion light years away! Not bad for a 5” refractor from a Bortle 7.1 sky.
Scope: 5” AP Refractor
Mount: AP900
Camera: ZWO ASI533MC with IDAS LPS 3 Broadband filter
Exposure: 3 hours
Processed in PixInsights
NGC 7331 distance 43 million light-years
NGC 7343 distance 343 million light-years
PGC 69402 distance 890 million light-years
PGC 2045849 distance uncertain (one source claims 2.2 Billion light-years)
PGC 69387 distance uncertain
PGC 141039 distance 1.15 billion light-years
PGC 141039 distance uncertain
PGC 2047594 distance uncertain
NGC 7340 distance 294 million light years
NGC 7338 is a double star
NGC 7337 distance 300-350 million light years
NGC 7335 distance 332 million light years
NGC 7336 distance 300-350 million light years
NGC 7333 distance 300-350 million light years
PGC 69291 distance uncertain
PGC 69281 distance uncertain
NGC 7331c distance 39.79 million light years
LEDA 2052629 distance uncertain
PGC 3088708 distance 2.2 - 2.55 billion light years
PGC 2051985 distance 290-400 million light years
NGC 7315 distance 283 million light years