| Date/Place | 2020-01-09 at Elijah Observatory | |
| Scope | Takahashi FSQ85ED | |
| Camera | QSI583wsg | |
| Integration | Using focal reducer. It is a RGB/H-alpha/OIII composition: RGB: 18 x 600 sec., bin 1 Hα: 25 x 1200 sec., bin 1 OIII: 25 x 1800 sec., bin 1 Image acquisition: Astroscheduler Processing: Pixinsight | |
| Comment | It is a very large HII region, whose distance is estimated at 7600 ly from us; its gas is illuminated by the stars of some clusters and associations of nearby stars, among which Cr 33 and Cr 34 stand out, two very large but unconcentrated open clusters, formed by giant blue stars born from the gases of the nebula. The light is then re-emitted by the nebula in the red color typical of the H-alpha hydrogen emission lines. Star formation is very active inside the nebula. OIII emission is very strong as well in the central regions of the nebula. IC1848 is a cloud physically separated from IC1805 and can be divided into two sections, indicated as W5-E and W5-W, respectively extended to 35 and 52 pcs. W5-E is the eastern section and contains a star of class O7V (a very hot main sequence star), BD + 59 ° 0578, whose stellar wind appears to be powerful enough to ionize the entire region in which it is located; W5-W, the western section, contains instead four O-class stars, but there could also be others in the eastern part of the region, not observable because they are completely hidden by the dense clouds. (Text adapted from Wikipedia) |
