This object is located in the constellation of Andromeda at a declination of +42 degrees. It spans 45 arc-minutes in our apparent view. This bright cloud is designated both as a LBN (bright nebula) object and a vdB (reflection nebula) object.
But is it really a reflection nebula?
This object has been identified as one of 4 parts (a, b, c and d) of vdB 156. Parts a, b, and c can be seen in more detail in
this image. Sources say that all 4 parts of vdB 156 are being illuminated by the blue magnitude 3.6 star Omicron Andromedae, which is about 1 degree off image to the upper right. Here is the Aladin sky atlas image:
It is interesting to me that vdB 156d is not more blue in color since the illuminating star is bright blue.
I do not believe that this is a reflection nebula that is reflecting the light of a single star. I think it is a molecular cloud reflecting the integrated light of the entire Milky Way, known as an IFN (Integrated Flux Nebula). This is due to 3 reasons - the uniform shading of brightness throughout the cloud, the lack of intense color in the cloud, and its large distance (16 degrees) from the galactic plane. I believe that the bright "central" star is simply superimposed from our view perspective and is at a different distance than the clouds.
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