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Object name: IC1805 - Heart Nebula   Optics:   TEC 140 Apo-refrakctor with original field flattener
  Objekt type: Emission nebula   Focal lenght:   980 mm
  Constellation: Cassiopeia   Camera:   FLI ML 16803-65
  Location / Date: Remseck / 16.01.2011   Exposure:   12 x 1200 sec H-alpha / 7 x 1200 sec OIII / 6 x 1200 sec SII / 1 x 300 sec RGB
  Distance: approx. 7500 Lj   Filters:   Baader H-alpha filter 7 nm / OIII-filter 8.5 nm / SII-filter 8 nm
  Apparent dimensions: approx. 60' x 60'   Mount:   10micron GM2000
  Real dimensions: -   Autoguiding:   Off-Axis Guider - SX Lodestar
  Brightness: 6.5 m   Software:   MaxIm DL / Registar / Photoshop CS3
  Position (R.A. / DEC): 02h 32' 35.57"/ +61° 29' 2.3"   Image processing:   Tone-Mapping-Method
 
 


Explanation:

The Heart Nebula, IC 1805 (SH2-190) is an emission nebula in the constellation Cassiopeia.
The nebula is formed by plasma of ionized hydrogen. The knot in the upper right is separately
classified as NGC 896 and was discovered first. The radiation of a small group of stars near
the nebulae's center, known as Melotte 15, drives the intense red output.


The colors are mapped in Hubble palette style:

red = SII
green = H-alpha
blue = OIII