There are more and less known objects in the sky, and one of the measures of popularity is the target’s number of names and symbols. The IC1805 emission nebula is also cataloged as Sharpless Sh2-190 and known as Heart Nebula or Running Dog Nebula. This part of the sky is quite dense with the interstellar matter, so there is quite a lot of other nebulae around. A bright cloud in the upper right part of the frame is known as Fish Head Nebula (IC1795 and NGC896). The young star cluster in the Heart center is Melotte 15 (Collinder 26), and there are also NGC1027, Markarian 6, and Tombaugh 4 open clusters visible in the image. The clusters in this region belong to the Cas OB6 association. The small oval left to the image center is planetary nebula WeBo 1.
The nebula spans almost two degrees in the sky (the image field of view is three by two degrees) and is located about 7,500 light years away from Earth. Nebula shape is formed by stellar winds from the hot stars in its core.
Full resolution here https://astrojolo.com/wp-content/uploads/2022/03/2022-03-24-I1805-3.jpg
I captured the data for this image in March 2022. It is 10 hours of exposures made with a hydrogen alpha narrowband filter. 6 hours with oxygen III filter and 2 hours with RGB filters. The telescope in use was TecnoSky 90/540 refractor with 0.8x FF/FR, the camera was QHY268M, and the mount iOptron CEM26. All these components are quite new in my stock and I am very happy about them – most happy with the camera, very happy with the refractor, and just happy with the mount 🙂
The hydrogen alpha data with the stars removed is presented below. In such monochromatic images, the structures and features are usually better visible, because the eye is not distracted by color information.
Full resolution here https://astrojolo.com/wp-content/uploads/2022/03/2022-03-18-IC1805H.jpg
And the last image is a detail comparison of the image made with a 90mm refractor and 254mm SCT telescope. The location was the same, the SCT image was made two years earlier. It is clearly visible, that a 90mm aperture can be a resolution limiting factor for amateur astroimaging, but of course not the only one. The seeing (atmospheric turbulence) has also a great impact on it.
Clear skies!
Image technical data: Date: March 2022 Location: Nieborowice, Poland Telescope: Tecnosky 90/540 Owl triplet Corrector: TS FF/FR 0.8x Camera: QHY268M Mount: iOptron CEM26 Guiding: ASI290MM + Sonnar 135 Exposure: about 10 hours through Ha, 6 hours of Oiii, and 2 hours withRGB filters Conditions: Bortle 6, transparency good, seeing medium
