Wikipedia Description: NGC 891 (also known as Caldwell 23, the Silver Sliver Galaxy, and the Outer Limits Galaxy) is an edge-on unbarred spiral galaxy about 30 million light-years away in the constellation Andromeda. It was discovered by William Herschel on October 6, 1784.[3] The galaxy is a member of the NGC 1023 group of galaxies in the Local Supercluster. It has an H II nucleus.[4]
NGC 891 looks as the Milky Way would look like when viewed edge-on (some astronomers have even noted how similar to NGC 891 our galaxy looks as seen from the Southern Hemisphere[9]) and, in fact, both galaxies are considered very similar in terms of luminosity and size;[10] studies of the dynamics of its molecular hydrogen have also proven the likely presence of a central bar.[11] Despite this, recent high-resolution images of its dusty disk show unusual filamentary patterns. These patterns are extending into the halo of the galaxy, away from its galactic disk. Scientists presume that supernova explosions caused this interstellar dust to be thrown out of the galactic disk toward the halo.[12]
NGC 891 appears alongside M67, the Sombrero Galaxy(M104), the Pinwheel Galaxy(M101), NGC 5128, NGC 1300, M81, and the Andromeda Galaxy in the end credits of the Outer Limits TV series, which is why it is occasionally called the Outer Limits Galaxy.[17][1
Acquisition Details
| Telescope | Takahashi TOA-130 |
| Optics | Takahashi TOA-645 Flattener |
| Filter | None |
| Camera | ASI2600MC Pro OSC |
| Integration Time | 13.8 hours |
| Subframes | 277 x 180 seconds |
| Date | 10 December, 2025 |
| Location | Carlsbad, California |