IC 63

Type:

Emission Nebula near the bright star Gamma Cassiopeiae (GC). The interstellar gas and dust in this region is radiated (UV) by GC which results in heating and ionization of neutral atomic hydrogen (H I) to ionized atomic hydrogen (protons, H II). Atomic carbon is also ionized by this radiation (C II). The hot hydrogen gas in the H II-regions glows in the red part of the spectrum. Some UV radiation is reflected by the gas clouds which leads to blue tones in the image.

The dust temperature can be estimated as 33.62 K and the radial distance between IC 63 and GC as 2.31 pc (~ 7.5 Ly) (see: J. M. Eiermann et al., MNRAS 529, 1680–1687 (2024))

Distance: ~ 550 Ly / Visual Brightness: 13.3 mag

A: Zoom [x 2] into the brightest region / B: H I intensity map of the region shown in A with the C II intensity contours overlaid from: [1] L. Bonne et al., The Astronomical Journal, 165:243 (12pp), 2023 June.
According to [1] H I (21 cm) data was taken from the measurements of the combine radio interferometry from GMRT in India, WSRT in the Netherlands, DRAO ST in British Columbia, Canada, and single-dish observations using the DRAO 26 m antenna.

The C II fine-structure line at 158 μm was observed with the upGREAT receiver (Heyminck et al. 2012; Risacher et al. 2016, 2018) onboard SOFIA (Young et al. 2012).

The H I intensity map shows a clumpy morphology. From the C II contour map it can be seen that there are regions with C II emission that do not have a counterpart in H I emission. The results of this obeservations can be explained by dynamical processes in these regions (L. Bonne et al.).

Date: August 22+23-th, 2024 / Moon ~70%(-)

Equipment:

Stellina 80/400, 1240x10s (3h 26min), darks, stacked: APP, post proc.: TOPAZ Denoise, FITSwork, Affinity Photo