It is also an example of a cocoon nebula
, a term that describes the dusty envelope that surrounds some newborn stars in the process of forming planets.
One of my favorite dark nebulae is Barnard 168, or as I call it, the Road to the Cocoon Nebula
. When I'm hunting for the position of the Cocoon (IC 5146) in my finderscope, I follow this narrow finger of darkness to the emission nebula's telescopic field.
The nebula was round and reminded me a little of the Cocoon Nebula
in Cygnus (IC 5146).
Another well-known imaging target, the Cocoon Nebula
(IC 5146) appeared quite grainy on the standard 5-minute exposure used by Dr Hewitt for all objects, a testimony to this nebula's extreme faintness.
At B168's eastern extremity lies the Cocoon Nebula
, an object too faint for binocular viewing.
Not far from M39 lie the Cocoon Nebula
and the spooky dark nebula Barnard 168, which S&T's Gary Seronik calls "the Road to the Cocoon." Here too is Pi' ([[pi].sup.1]) Cygni, which has one of my favorite preposterous names: Azelfafage ("ah-ZEL-fuh-fahj," a medieval corruption of the Arabic name "the Tortoise").
It's a cinch to follow B168 to its end, which engulfs IC 5146, the Cocoon Nebula
. At first I couldn't see the nebula, but when I added a hydrogen-beta (H[beta]) filter it was immediately apparent, with a 10th-magnitude star at its heart and another at its southern edge.
Another quarry in Cygnus is the 2 [degrees] long Barnard 168, which meanders to and engulfs the Cocoon Nebula
(IC 5146) at its eastern end.