September 2016

As you might expect, there was an increase in section activity in September, as weather conditions slowly improved and nights became longer.  Four members sent in between them fifteen images and two drawings of deep sky objects.

Steve Norrie, observing from Fife, produced thirteen of the fifteen images.

NGC 7635 is the Bubble emission nebula in the constellation of Cassiopeia, IC 5146, the Cocoon emission nebula in Cygnus, IC 1805, the Heart emission nebula in Cassiopeia, and M33 the Pinwheel spiral galaxy in Triangulum.  M33’s spiral arms are very loosely wound with low surface brightness, and for visual observers is probably best seen with binoculars.

NGC 7635
IC 5146
IC 1805
M33

The next four images are of M101 a face -on spiral galaxy in the constellation of Ursa Major, NGC 40 planetary nebula in Cepheus (aka the “bow – tie” nebula and Caldwell 2), NGC 281, the Pacman emission nebula in Cassiopeia and NGC 6960, a part of the Veil supernova remnant in Cygnus.

NGC 281 includes the open cluster IC 1590, and contains several Bok globules, where new star formation is probably occuring due to the gravitational collapse of cosmic dust and gas.

M101
NGC 40
NGC 281
NGC 6960

 

 

 

Here are images of NGC 6992, another part of the Veil supernova remnant in Cygnus, a second image of M33 in Triangulum, NGC 7023 reflection nebula in Cepheus and NGC 7331, a spiral galaxy in Pegasus.  This image also contains a group of galaxies to the lower left known as Stephan’s Quintet.  NGC7331 itself is the largest member of a five – galaxy group, the smaller members are sometimes called the “fleas”.

NGC 6992
M33
NGC 7023
NGC 7331

 

Steve’s final image this month is NGC 6888, the Crescent emission nebula in the constellation of Cygnus.

NGC 6888

About 5000 light years from the Earth, the nebula is being formed by the collision between slow moving material ejected from Wolf – Rayet star WR 136 when it was in its red giant phase and the faster current stellar wind.  The  collision shock – wave gives rise to temperatures sufficient to produce X rays and ionise the gas.  Steve used an ES 127 APO refractor at focal ratios of f5 and also f 7.5 and an Atik 490EX colour camera.

 

David Davies, observing from Cambridge,  imaged a part of the Veil nebula supernova remnant in Cygnus known as Pickering’s Triangle.  David employed a 200mm Richey Chretien telescope at f5.6 with a QSI583 camera and red, blue and green filters.

NGC 6979

 

 

Ian Papworth sent in this image of NGC 6826, the Blinking planetary nebula in the constellation of Cygnus;  so called because in the eyepiece it is best viewed with averted vision, and tends not to be seen when looked at directly as the brightness of the central star overwhelms the nebula.

NGC 6826

Michael Kinns sent in two drawings of globular clusters.  M2 lies in the constellation of Aquarius, and to M71 is in Sagitta.

M2
M71

M71 was thought to be an open cluster until quite recently (1970’s)  due to several factors including lack of a dense core, and an age of around 10 billion years (young for a globular).  It’s stars contain more metals than usual for globulars, and M71 lacks the RR Lyrae variable stars found in most globulars.

 

Dave Finnigan