October 2016

Six section members submitted their observations this month, in total twenty five digital images.

Mark Beveridge of Aberdeen sent in seven of these.  Here is M2, a globular cluster in the constellation of Aquarius then M27 the “dumbbell” planetary nebula in Vulpecula, NGC 6781 planetary nebula in Aquarius and NGC 7009, also a planetary nebula in Aquarius also known as the Saturn nebula;  which bears a resemblance to the nearly edge – on ringed planet.

M2
M27
NGC 6781
NGC 7009

Next is an enlarged, cropped version of the NGC 7009 image, then M57 the Ring planetary nebula in Lyra, M74 spiral galaxy in Pisces and NGC 1579 emission nebula in Perseus.

NGC 7009
M57
M74
NGC 1579

The latter is sometimes called the Northern Triffid and is a HII region of new star formation about 2,000 light years from the Earth.  It resembles M20, the Triffid nebula in Sagittarius, having both emission and reflection components, plus dark lanes of dust; in fact much of the visible spectrum light from the young stars is being obscured, and infra red telescopes are required to study them.  Mark used a 140mm f14.3 Maksutov-Cassegrain telescope and SXR-H814 camera plus R, G and B filters.

 

Geoff Elston, SPA Solar section Director, also sent in seven images taken via an 80mm refractor and Canon D550 DSLR camera.  The first two are the planetary nebulae M27 and M57 also seen above;  it is interesting to note the kind of image each telescope/camera combination can produce.

M27
M57

Geoff’s next four images are, M31 spiral galaxy in the constellation of Andromeda, M39 open cluster in Cygnus, NGC 6910 the Rocking horse open cluster also in Cygnus and globular cluster NGC 6934 in Delphinus.

M31
M39
NGC 6910
NGC 6934

 

 

 

Geoff’s final image is of NGC 6960, the western part of the Veil supernova remnant in Cygnus.  Estimates of the age of this object vary widely between 5,000 and 8,000 years.  It is around 1,500 light years from the Earth.  The whole remnant covers an area of around three degrees, or six times the diameter of the full moon.

NGC 6960

                                                                                                                  

Ian Sharp imaged edge – on galaxy NGC 891 in  the constellation of Andromeda.  It is a member of the NGC 1023 group of galaxies and is around 30 million light years from the Earth.  It is thought that our own galaxy the Milky Way would look very much like NGC 891 if it were possible to view it edge-on from a great distance.  Ian used a 250mm Schmidt Cassegrain telescope and an Atik infinity one-shot colour camera to capture this image.

NGC 891

Dave Hancox of Dalmellinton imaged three emission nebulae with a 102mm triplet refractor and a QHY 8L camera.  First is IC 396, the Elephant’s trunk nebula in the constellation of Cepheus.

IC 1396

Here are NGC 6888, the Crescent nebula and NGC 7000, the North America nebula;  both of these in Cygnus.

NGC 6888
NGC 7000

The Crescent is unlike the others, because it is the stellar wind from a Wolf Rayet star that is causing the gas it expelled when it was in the red giant stage to become ionised.  On the other hand, it is young, hot stars producing the ionisation in the gas and dust clouds from which they were formed in IC 396 and NGC 7000.  In both cases, it is when ionised hydrogen, (HII), recombines with an electron and then emits a photon of wavelenth 656.3 nanometers, that the charactristic pink/red glow is produced.

 

Steve Norrie of Fife sent in five images;  the first two are emission/dark nebula IC 434 is the Horsehead in the constellation of Orion and IC 5070 the Pelican emission nebula in Cygnus.

IC 434
IC 5070

Steve’s next three images are M1 the Crab supernova remnant in Taurus, M81 or Bode’s galaxy in Ursa Major, and M74 galaxy in Pisces.

M1
M81
M74

M74, featured twice in this report, is about 32 light years from the Earth.  Face-on, and with a low surface brightness, this magnitude 10 galaxy can be hard to see in the eyepiece of a telescope regardless of aperture.  Supernovae have been seen in M74 in 2002, 2003 and 2013.  The 2002 event was a rare type 1c which means the progenitor star possessed almost no hydrogen and little helium.  This corresponds to a type of Wolf Rayet star, probably with an initial mass of more than nine times that of the sun.  Steve used a 127mm f5 refractor and an Atik 490 EX one-shot colour camera for these images.

 

David Davies of Cambridge sent in two images.  The Deer Lick group of galaxies, most prominent of which is NGC 7331, lies in the constellation of Pegasus.  Hickson 92, better known as Stephan’s Quintet, is also in Pegasus.  David secured these images via a 200mm Richey Chretien telescope and a QSI583 camera plus R,G and B filters.

NGC 7331
Stephan’s Quintet

 

Dave Finnigan