Quote:
Originally Posted by sally1jack
Nice report Paddy,
I've just got my new scope & you guys have sparked my interest.
Thanks phil  |
Hi Phil,
I don't know what is your exact level of observing experience, but I
do know that most Deep Sky observers are obsessed with seeing the
faintest parts of spiral galaxies ; the spiral arms!!
I can understand this, because all Visual Observers want and need to push their eyes to the absolute extreme-limit of detection, when viewing Very Low Surface Brightness (= intensity divided by sky area) nebulae and galaxies.
[[ In fact there is an amazing resource on techniques that can be used by observers in order to see
as faintly and
as accurately as possible ; the thread called "How to Hone Observing Sensitivity and Accuracy" ]]
However, strangely, I have become something of a contrarian, and I have campaigned to popularize the great and enduring interest of the
brightest and most easily detectable part of a galaxy.......the central part, nearest to the centre of a galaxy.
Some of the most intriguing, mysterious, and important phenomena are viewable in
the bright central parts of galaxies:
(1)
Active Galactic Nuclei ( a good example is the "stellar-appearance" nuclei of NGC 1566 and M77)
A more distant example is the powerful Seyfert Nucleus that is seen within the distant edge-on spiral IC 4329A
(2)
Rings of supergiant HIIregion/OB-star complexes surrounding the "stellar-like" true nucleus of a galaxy. A very good example is the easily observable star-forming ring which is seen at the centre of NGC 1097
(3)
Nuclear Star Clusters, which are actually similar to a very-overluminous globular star cluster that contains several different ages of stars. One of these that might be visually observable is the Nuclear Star Cluster at the centre of NGC 300. (A related type of object is the "young globular star cluster" found in NGC 1705)
(4) Small bright
bulges (spheroidal structures) seen at the centres of many galaxies that have long and strong bar structures
(5)
Mini-bars : Mini-bars are tiny and Very Bright bar structures that are completely distinct from the large-scale bar found within a barred-spiral galaxy. Some galaxies have a small bar which is nested within a larger bar!! (I seem to recall that NGC 1291 has an exceedingly faint & low-contrast "large-scale bar", but it
also has a Very-high-contrast & Bright central Mini-bar structure)
cheers,
Mad galaxy man
Other galaxies with prominent Nuclear Star Clusters include NGC 7793 (see recent imaging thread about sjastro's NIR image of this galaxy) and NGC 4244