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In 1962, Beverly T Lynds catalogued the dust cloud that separates the North American Nebula (NGC7000) from the Pelican Nebula (IC5070). These dust tendrils leak into the glowing ionised hydrogen gas that form one of the largest emission nebulas in the summer sky. This region is often captured with narrowband imaging. However, since I prefer natural looking colours, I decided to go for an LRGB image with a Ha blend into the red channel. The image below represents 18.5 hours integration and was taken with my Esprit 150

Annotated version of NGC3953

NGC 3953 is a barred spiral galaxy located in Ursa Major and is a member of the M109 galaxy group. It’s about 55 million light years distant with a diameter of 100 000 light years. Observed from Earth, it has a high angular inclination, 29 degrees from edge on, with a bright active nucleus and inner dust lanes. The spiral arms contain young bright blue stars, whilst the pinkish regions indicate the presence of ionised hydrogen and star forming regions. Two supernova’s were also discovered in 2001 and 2006. The background also contains a handful of more distant background galaxies which I’ve labelled in the annotated version of the image. Interestingly, the galaxy PGC2832088 identified by Pixinsight is not visible, so I presume it must be extremely faint. The LRGB image was taken with my Esprit 150 and represents 17 hours integration time.

I haven’t come across many images of this on SGL, probably because due to it’s small apparent size. Anyway, I think the area is interesting and it includes a lost nebula ! Located in Taurus, Hind’s variable nebula (NGC1555) is about 4 light years across and 400 light years distant. It was discovered in 1852 by John Russell Hind. After discovery and over a period of several years, the objected slowly faded from view and eventually disappeared. In the early 20th Century, it became visible again leading astronomers to categorise it as a variable nebula. The object is a variable reflection nebula and is illuminated by the bright golden variable star T Tauri which can been seen at the centre of the image below. The very young star was born in the nebula and is pre-main sequence. The nebula changes in brightness as the clouds move around the star with the result is that the star and nebula do not appear to brighten at the same time. Another object, in the vicinity of Hind’s variable nebula, is known as Struve’s Lost Nebula. This was reported by Otto Wilhelm Struve in 1868 and verified by Heinrich d’Arrest. It was subsequently given a separate catalogue number (NGC1554) by Dreyer. It subsequently disappeared and is absent on photographic surveys. It has been speculated that the nebula may have been a transient portion of the reflection nebula complex which extends around this region of space.