| Object name: | Constellation: | Coordinates: | Apparent size: | Visual brightness: |
|---|---|---|---|---|
| NGC 4725 | Coma Berenices | 12h50m / +25°30' | 11.0' x 7.4' | 9.3 mag |
The beautiful barred spiral galaxy NGC 4725 with its prominent ring structure in the constellation Coma Berenices. NGC 4725 is a Seyfert Galaxy, suggesting an active nucleus probably containing a supermassive black hole. NGC 4725 is the brightest member of the Coma I galaxy Group and is about 40 million light-years from Earth. In the same field of view, the spiral galaxies NGC 4712 and NGC 4747 can be seen (see annotated version of the image further down the page, Fig. 1a). NGC 4712 is 196 million light-years from Earth, NGC 4747 a mere 32-35 million light-years. NGC 4725 and NGC 4747 were discovered by Frederick William Herschel in 1785, while NGC 4712 was discovered by John Herschel in 1832 (source: Wikipedia).
Fifty-nine 3-minute exposures (177 minutes total exposure) at gain 100, taken on April 12, 2024, were added for this shot with Astro Pixel Processor (APP) software and the final image processing was done in Photoshop. Darks, flats, bias and darkflats were used.
Equipment: Cooled ASI 2600MC Pro camera at -10°C, TeleVue Paracorr Type II coma corrector, 8" f/5 "ONTC" newtonian telescope riding on a ZWO AM5 Strain Wave Mount, ZWO OAG-L off axis system, ASI 174MM Mini guide camera, ASIAIR Plus.
NGC 4725 was also captured with a 16-inch dobsonian on an equatorial platform with a simple DSLR camera. The image can be seen here.
