|
| If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|||||||
|
|
Thread Tools | Display Modes |
|
|
|
#1
December 18th 07, 01:02 PM
posted to uk.sci.astronomy, sci.astro.amateur, sci.astro
|
|||
|
|||
NGC 7023 (Caldwell 4) - a reflection nebula in Cepheus
Exploring the Digitized Sky Survey
NGC 7023 (Caldwell 4) - a reflection nebula in Cepheus The effect of stretching the image, using the Digital Development option in MaxIm DL, can be quite dramatic. This is one of the reason why I am concerned when I read about the discovery of new astronomical objects based on short exposures using small telescopes. I think it is quite clear from the image that the cloud of gas and dust known as Caldwell 4 is significantly larger than just the portion reflecting the star light (and hence appearing blue) - look at the dark zones around the perimeter where there are few, if any, stars. http://martin-nicholson.info/ngc7023/ngc7023.htm Martin Nicholson, Daventry, England. http://www.martin-nicholson.info/1/1a.htm Visit the Astronomical Hall of Shame at http://www.geocities.com/queen5658/ 
|
| Thread Tools | |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| NGC 7023 (Caldwell 4) - a reflection nebula in Cepheus | ukastronomy | Astronomy Misc | 0 | December 18th 07 01:02 PM |
| IC 1396A Elephant Trunk Nebula in Cepheus | Anthony Ayiomamitis[_3_] | Amateur Astronomy | 1 | September 16th 07 06:06 PM |
| NGC 7023 - Iris Nebula in Cepheus | Anthony Ayiomamitis[_3_] | Amateur Astronomy | 2 | August 27th 07 10:44 AM |
| ASTRO: NGC 7023 Iris Nebula | Rick Johnson[_2_] | Astro Pictures | 6 | January 30th 07 12:24 AM |
| Largest reflection nebula | Richard | Amateur Astronomy | 2 | August 29th 04 09:59 AM |
Hybrid Mode
