UGC 3691: a Vera Rubin Galaxy
| Designation(s) | UGC 3691 |
| Object Type(s) | Galaxy |
| Relevant Catalog(s) | All (Chron) |
| Obs. Lat/Long | 42° 17', 073° 57' |
| Constellation | Gemini |
| Date and Time Observed | 2026-04-20 22:06:00 |
| Instrument | EdgeHD 8" w/f7 reducer-1,422mm FL |
| Camera | Player One Apollo-M Mini |
| Image Details | Up is 179.9 degrees E of N. Transparency: Good. Seeing: Fair. Total integration time was 51m. Exposures 20s@225g, No Filter. Dithered and recentered in SharpCap. No guiding. |
| Description | At 13.4 magnitude in the B band, and only 2' x 1' in size, this is a tiny, relatively dim galaxy for Vera Rubin to be measuring. Still, on inspection, it's a classic, regular, Sc spiral, perfect for her rotation measurement. UGC, the Uppsala General Catalog of Galaxies, was published in 1973 with something like 12K galaxies. It is an outgrowth of the Zwicky Catalog of Galaxies and Galaxy Clusters which came out of a project to identify all galaxies above magnitude 15.5 captured in the 1958 POSS survey images. The Zwicky catalog was published in 6 volumes between 1963 and 1968 and listed some 30K galaxies. The UGC listings selected the brightest of them, and unusually carries forward the morphological classifications that Zwicky's team created. This would have made it relatively easy for Vera to select it. |
| Catalog Links | All Listings |
