Huser Astro Gallery - Nebulae

Click on photos to enlarge. 

M1, The Crab Neb in Tau is the Supernova remnant from July 5, 1054. Chinese records described the event. The SN reached mag –13! Distance is 6,300 l-y. The central star, a white dwarf, is a neutron star and a fast pulsar.

 M82 in Uma is an unusual spindle-shaped nebula, not an edge-on spiral. Its center has a large black hole.

M57 or the popular Ring Nebula in Lyr (NGC6720). Its central star is a bluish sub-dwarf, very hot 100,000 degrees and likely near its end. The Ring is at a distance of 1500 l-y and its diameter about 0.5 l-y. It is estimated that the central star ejected the nebula approx 20,000 yrs ago, but not in a nova-like explosion. Spectrographic imaging shows distinct wavelengths in the ring, while the central star gives just a colored streak.

M46, OC in Pup, is at 5,000 l-y distance; ringlet nebula, NGC2438, is 3,000 l-y away. The central star is one of the hottest white dwarfs in our MW, 75,000 degrees K; our Sun is 5,800.

M16, The Eagle, is a large star cluster in a large diffuse nebula in Serpens. A real beauty, but it requires a long exposure. Its center features the “Pillars of creation”; three denser clouds where stars are being ‘born’. The Eagle is 8,000 l-y away and located in the Sagittarius arm of our MW. The Pillars are about 3-6 l-y in length. Some of the stars are brilliant (several 1000 times our Sun) and young.

M16, The Eagle

M8, Lagoon, is a fine diffuse nebula, just visible with the unaided eye and easily mistaken for a comet. A photograph reveals its fine details. Barnard’s nebula B88 and NGC6530 are almost part of the Lagoon

M17, The Swan (Omega is also used), is a diffuse nebula in northern Sagittarius. Easily mistaken for a comet because of its shape as a ‘streak’. Imagine the ‘streak’ as the body of a swan, then the hook at the eastern end can be viewed as the neck and head of a swan (with some effort). The Swan is almost 6000 l-y away

 M17, The Swan

 M20, Trifid nebula, is only 1 degree north of M8, and consists of three fairly distinct irregular nebulous parts. A bright triple star is near center. A nice nebula and easy to photograph.

The Veil in Cygnus, NGC6960 (western part), 6979, 6992 and 6995 (eastern portion) are parts of the Cygnus Loop, remnants of a SuperNova of 10,000 years ago. Must have been a bright one! It is large, about 3 degrees-of-arc and only 2,000 l-y away. Beautiful photographic object, but some sensitivity in IR is needed. Usually photographed in sections.

The Veil in Cygnus, western portion


  The Veil in Cygnus, western portion

 The Veil in Cygnus, eastern 

The Veil in Cygnus, eastern portion

 The Crescent Nebula, NGC 6888 in Cyg, is only 4,800 l-y away and is 20’ across in the sky. It has luminous shells around Wolf-Rayet star WR136. The star’s eruptions (periodic at abt 10,000 years) started 250,000 years ago and the ejected gasses, blown by the stellar wind of WR136, are colliding with the surrounding “stuff”. The shockwaves are creating the complex shell structure and the UV of WR136 ionizes the gas which creates the luminosity. Soon (few million years) WR136 will explode as a SuperNova.

 Herbig-Haro (HH) objects are shock regions associated with star-births and have characteristic spectra. The image contains several of these objects; these are the dark ’pipes’. The shockwave causes ‘stuff’ at one end to go faster than at the other, so you get a ‘bunching up’ effect. This speeds up star formation enormously as compared with gravity alone.

M17, or Swan, Omega or Horseshoe Nebula in Sgr (Sagittarius), a large and beautiful diffuse nebula of 45’ x 35’; mag 9 and at a distance of 6,000 l-y.

NGC 7635, Bubble Nebula in Cas, a near spherical cloud of gases and dust lit up and excited by a central star. Its stellar wind "blows up" the bubble. Part of a large molecular gas cloud.

 NGC 281. Another nice nebula in Cas. Note the small rectangular dark dust spot above the center of the nebula.

 Bubble Nebula, NGC 7635 Bubble. A longer, 20 times 180 sec, exposure paid off. Compare with the earlier one.

 The whole cluster 1396 is abt 3 x 2 degrees; B161 or IC1396A is the dark nebula, the “Trunk”, only 13 x 3 arc-min. Distance is abt 2,500 l-y. In the center is a reflection nebula (“vdB 142”) around star HD239710, mag 9. Our CCD has IR sensitivity and we did not use filters; exposure was 10 x 150 sec or 25 minutes.


 @1: The Cone Nebula in Ngc 2264 (constellation Monoceros). We had a workshop on processing our FITS files; 30 exposures of 120 sec had to be “stacked”, combined, into a one-hour image with CCDSoft, AIP4Win and PhotoShop. This is the “Add” one of CCDSoft. 

 @2: This second image is the “Average” combination, using 3 series of 10 exposures in AIP. As expected the previous one tended to a slight over-exposure, but showing the nebula’s structure better than this “average” one, which showed the stars much better. 

@3: The “AIP4Win” (Astronomical Image Processor for Windows) with the non-linear (or “curves”) feature, combines the advantages of the two prior processes (and then some). This result can be compared with the ultimate image of the Cone, the NASA photo.

  @4: This detail of the Cone is from NASA’s image of Ngc 2264. The dust and gas clouds are the cradles for star births. The stars are indeed young and hot, blue. The nebula is 2,600 l-y away, located in Monoceros, and the dark absorption nebula, the “Cone”, is 7 l-y long.

 @5: IC 443, the “Jellyfish Nebula” in Gemini, is the remnant of a SuperNova. Again we’ll show three different processing procedures. This one is the “add”-stack in CCDSoft of the 30 exposures of 120 sec.

 @6: Tom Bennett applied PhotoShop features to enhance contrast etc. The Jellyfish is part of a “planetary nebula” structure of a super nova event. Probably a second event blew most of the ring structure away and the remaining central neutron star was out of our field-of-view and had moved away from the original center of the nebula.

@7: AIP4Win v. 2.3.1 has been applied for this image and shows good contrast and resolution. Our workshop taught us that personal tastes and experiences do influence the final results as much as the different processors. These three images of IC 443 are hardly significantly different, we concluded.

Our Halloween “special”: VdB141, Sh2-136 or “Ghost Neb” in Cep is 1,200 l-y away and 2 l-y across.
The star, just visible in the bright portion of the ghost, excites the hydrogen and illuminates the dust of the nebula; it is a young one not even on the “main sequence” yet and still picking up hydrogen.
The star is of the FU-Orionis type (“FUORs”). In 1936 FU-Ori brightened from mag 16 to 10 in a few months; just the opposite of a SN.
The core of the the dark cloud, on the spooky arm farther to the right, shows likely the birth of a binary star. Now it is still a reddish and diffuse dot.

The Horsehead Nebula in Orion, a dark nebula, B33, against IR nebulosity, IC434. The ‘little’ horse head’s size is one l-y or 6 trillion miles!