A "Helping Hand" – one of the popular nicknames for this dark nebula, but it is also known as the "Giving Hand", "Bowler Hand", and "Cosmic Hand" among astrophotographers.
Faint and dense cosmic dust in the northern area of the Cassiopeia constellation is found here. This area includes two different kinds of nebulae. One of which is a reflection nebula, dust clouds that lightened up by reflected light of nearby star and second is totally the opposite, the dark nebula, were dust clouds so cold and compressed that they absorb all of the light coming from background stars, which is also makes these objects very challenging to image.This whole area is a rich complex of dark nebula, but most obvious and largest of them near the top right, under their cataloged name (Lynds Dark Nebula) LDN 1357 (Fingers), LDN 1355 (Palm) and above the center LDN 1358 (Shoulder).
On the left side, somewhat bright golden reflection nebula is VDB 7 (Van Den Bergh Catalog), which lies in proximity of a bright variable star RZ Cass. RZ Cass is a white eclipse star of 6th magnitude, which makes it harder to do observations of VDB 7 nebula, being at 4.6 magnitude. Interestingly, RZ Cass is not the star that illuminating VDB 7 nebula, but a much weaker star of 11th magnitude in the area.
On the right side, just below the "hand", is another reflection nebula – VDB 9. This reflection nebula does get illuminated by embedded bright variable star SU Cass. Dust of VDB 9 reflecting the light from SU Cass and makes visible it's lined up structures, with bluish tint which often associates with reflection nebulas. SU Cass is about 1400 light years away, while RZ Cass is only about 200 light years away.
Description credit:
https://www.myastroscience.com/vdb9vdb7 (and another great image of these nebulae).
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