Some Early-Morning Showpieces

 While hunting nearby stars in the pre-dawn hours on Oct 25, it was hard to resist pointing the camera at some well-known showpiece objects.

Horse-head nebula

Messier 35 + NGC 2158

Messier 41

Messier 42+43 (and satellite tracks)

Messier 46 (left) + Messier 47 (right)

All images are with an Olympus E-P5 + Rokinon 135mm f/2 lens, ISO 1600, 60 s exposure.  Cropped to 2° field of view.  There was some strong green airglow on this morning (sqml=21.25), so the stars take on a more reddish hue than normal after compensating for the green background.

Messier-catalog objects are usually abbreviated as M41, M42, ..., etc.  The Horse-Head Nebula (Barnard 33) is a dark nebula silhouetted against the glow of the emission nebula IC434.  It sits just below the bright star Alnitak at the end of Orion's belt.  The Horse Head, along with the Orion Nebula (M41), the Andromeda Galaxy (M31) and the Pleiades (M45), is one of the most photographed objects in the sky.  And, why not?  These are all iconic celestial sights and everyone wants their own personal memento.

Messier 35 is an open cluster in the constellation Gemini, about 3000 ly distant.  The fuzzy blob to the right and below M35 is another open cluster, NGC 2158.  This cluster is much farther away, about 16,500 ly.

Messier 41 is an open cluster in the constellation Canis Major, about 4° below Sirius. In a dark sky it is visible to the naked eye and was possibly recorded by Aristotle in 325 BC.  It is about 2300 ly distant.

Messier 42, otherwise known as the Orion Nebula, is the bright naked-eye nebula in the Orion's Sword asterism.  It is one of the nearest star-forming regions to our solar system at a distance of about 1400 ly.  M43 is the smaller comma-shaped blob detached just above the main nebula.

Messier 46 and Messier 47 are open clusters in the constellation Puppis.  M46 is about 4900 ly distant and M47 is much closer at 1600 ly.  There is a planetary nebula (NGC 2438) in the same line of sight as M46, visible as a small bluish blob in the image above.  This nebula is a foreground object and not part of the cluster.