IC 1805

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Observation place
New Mexico


TelescopeTakahashi FSQ 106ED - Diam. 106 mm (4,2 ″), foca. 530 mm, f / 5 
MountParamount ME
Imaging cameraSBIG STL 11000 regulated at -15o Celsius
Image typeHa (RVsB) (Vs for synghetic green)
ExhibitionHa (11 x 10 'bin 1 × 1), RB (4 x 3' bin 2 × 2 each)
PretreatmentMaxim DL
TreatmentPhotoshop and PixInsight
Specific treatmentCreate a synthetic green image

Object description

Object typeEmission nebula and open cluster "The heart nebula"
Visual magnitude6,5
Distance7500 light years
Dimension seen from EarthApproximately 190 'x 155' of arc, official data 60 'x 60' of arc
We can clearly see in the image the famous heart that the nickname of the nebula evokes. This large, faint nebula is made up of hydrogen gas ionized by ultraviolet radiation from hot young stars. It contains, in its center, the dense open cluster IC1805. The nebula, nicknamed the Heart Nebula, is much larger than the open cluster, which is confusing. Indeed, the nebula of the heart has a dimension of approximately 190 'by 155', while the open cluster (which one calls the nebula of the heart) covers 60 'by 60'. Before photographing this nebula, it is imperative to take this fact into account because, if we trust the official dimension, we will take a single small portion of the Heart nebula.  

The heart nebula encompasses several objects listed in astronomical catalogs. We see, at the bottom to the right, the nebula IC1795 (NGC896) that I photographed on October 9, 2012. We also see the open cluster NGC 1027 at the top center, slightly to the right. We can also see the open cluster MK6 to the left of the nebula, slightly downwards. To the far left, outside the nebula and slightly upwards, we can see the open cluster K4. There are also other objects inside the Heart Nebula.  

Unlike the bright 6,5 magnitude open cluster, the nebula is much less so that it is hardly visible in even a large telescope. To see the Heart nebula properly in a long exposure photograph, it is imperative to use an H-Alpha luminance image which will bring out the hydrogen gases that make up most of the radiation from this nebula. Without the use of this filter, the nebula will remain visible and will be obstructed by the large number of stars that compose it.
Richard Beauregard
Sky Astro - CCD
My impression "We cannot be alone in this gigantic universe"