Sunday, September 23, 2012

Autumn swansongs

 The Cygnus constellation shines during autumn high in the sky and inside its boundaries there are plenty of interesting objects - star clusters and nebulaes, emission ones but also the dark nebulaes that can be observed due to the light extinction.

At the first picture there is the brightest part of Sh2-101 nebula also knows as Tulip. This cloud is placed about 6000 light years away. Also in the picture you can see the x-ray source Cygnus X-1. In the left part of the picture there are two bright stars. The one more to the left and little bit higher is Cygnus X-1
Picture taken with modded Canon 20D camera and GSO 6" f/5 newtonian with exposures 50x5 minutes.

Next picture is IC1318 Butterfly Nebula (also known as Gamma Cygni Nebula). This one consists of three part - you will find parts B and C at the picture. It is about 3700 light years away and it is typical emission nebula that red tint comes from hydrogen alpha emission. 
Picture taken with the same setup as above with 45x5 minutes total exposure.

Another picture is Eastern Veil nebula (NGC6992) aka Cygnus Loop or Cirrus nebula or Filamentary Nebula. Its western part is NGC6960. The whole complex is the supernova remnant that happened 5 to 8 thousands years ago. It is placed about 1470 light years away. The nebula has been observed for the first time in 1784 by William Herschel. Its total brightness is pretty high, but also it is quite large, so the effective surface brightness is low and it is hard to observe.

Western Veil NGC6960.
Besides these two Veil parts there is also a Pickering Triangle that is the part of this supernova remnant. It's surface brightness is quite low however.
Exposition time for Eastern Veil was 50x5 minutes, for Western Veil it was 70x5 minutes (my longest exposure so far).

Clear skies!