This object, also known as LBN 105/106, is a faint molecular cloud located 700 light years away in the constellation of Hercules at a declination of +22 degrees.
This nebula is included in the Sharpless catalog of emission objects but is now believed to be an IFN (Integrated Flux Nebula).
At 700 light years away, it is one of the closest molecular clouds to earth. It is about 1.5 degrees wide, which at that distance corresponds to a width of 20 light years.
Our apparent view of this faint object is almost edge-on to the common horseshoe shape of a molecular cloud.
LBN 468 is the most popular example of this shape, seen here is an almost face-on view. More horseshoe shapes can be seen in my
Astrobin Molecular Cloud Collection.
I find IFN to be fascinating. FYI, here is one definition of IFN from Wikipedia: "
Integrated flux nebulas are a relatively recently identified astronomical phenomenon. In contrast to the typical and well known gaseous nebulas within the plane of the Milky Way galaxy, IFNs lie beyond the main body of the galaxy. The term was coined by Steve Mandel who defined them as "high galactic latitude nebulae that are illuminated not by a single star (as most nebula in the plane of the Galaxy are) but by the energy from the integrated flux of all the stars in the Milky Way. As a result, these nebulae are incredibly faint, taking hours of exposure to capture. These nebulae clouds, an important component of the interstellar medium, are composed of dust particles, hydrogen and carbon monoxide and other elements. They are particularly prominent in the direction of both the north and south celestial poles." Sh2-73 has a relatively high galactic latitude of about 45°.
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