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UGCA 334 - The Hardcastle`s Galaxy

OBSERVING REPORT

UGCA 334 - GALAXY IN CENTAURUS (THE HARDCASTLE NEBULA)

Date: February 9, 2016
Time: 01:30am local time (04:30am UT)
Telescope: 8" (20cm.) f/6.5
Observer: Leo Cavagnaro







Click on the image to enlarge
Finder Chart
13h 12m 56s   -32 41' 18" (J2000.0)


How to find it,
About 4°30to the north-northwest of the 2.8 magnitude star Iota (ɩ) Centauri.
Stars in map up to visual magnitude 6.


Go to a good observing site and wait for sunset. Once you have very
dark skies aim your telescope to the north part of the constellation 
Centaurus to try to catch the Hardcastle`s Galaxy.
Photo taken by Leo Cavagnaro from the observing site.
If you are the owner of an 8-inch telescope or similar and want to observe this faint galaxy, just put your eye to work! Moreover, you need a very dark and steady sky to try to glimpse this "ignored galaxy". I say "ignored" because there is not too much bibliography and information about it taking into account that it is a target that several amateur observers can include in their observing projects. Well, maybe that has sense because there are much more interesting objects in the area where UGCA 334 resides like the big and beautiful galaxy Messier 83, situated about 6° east-northeast of it, or the less conspicuous but still interesting galaxy NGC 5102, which lies 4°5 southeast of UGCA 334, very close to the bright star Iota (ɩ) Centauri.

The Uppsala General Catalogue (UGC) is a list of galaxies published by Peter Nilson in 1973. It lists a total of 12,940 objects and is limited to the sky north of Declination -2°5. UGCA is an addendum of the Uppsala General Catalogue. According to Brian Cudnik in his book "Faint Objects and How to Observe Them" UGCA is a supplement that contains 444 objects of special interest south of the declination limit. However, I have found some UGCA galaxies with positive declination like UGCA 86 and UGCA 92 in Camelopardalis. UGCA 334, named "Hardcastle Nebula" by the SIMBAD Database and cataloged in that website as a "Galaxy in Cluster of Galaxies", is one of such objects. It is, undoubtedly, a faint galaxy, but it is bright enough to be seen with bigger telescopes that several observers usually have (e.g. 12, 18, 24-inch).

DSS image of UGCA 334. North is up.
I observed this galaxy in early February 2016, when constellation Centaurus reaches a good altitude around 1am local time and later, being visible just a few arc minutes of the zenith before sunrise.

UGCA 334 (also MCG-05-31-039, AM 1310-322, ESO 443-83), discovered by J. A. Hardcastle from the Franklin-Adams plates, reaches a very high altitude for any observing site at a latitude around -35°, so this part of the planet is perfect to try to see it. If you are as far north as +47° latitude the galaxy will be technically above the horizon, reaching about 10° when transiting the local meridian. However, I think this is not a good altitude to see a faint object like this one.

At least in projection, UGCA 334 lies very close to the galaxy cluster ACO 3544 (see map below) which appears listed in Table 4. Clusters of galaxies in the area of the Shapley Supercluster, in the paper "Structure and dynamics of the Shapley Supercluster" D. Proust et. al. 2006. However, I could not get enough information to find out if UGCA 334 is a real member of ACO 3544 or just a field galaxy. 

Using an 8-inch Newtonian telescope working at low magnification (42 and 78x) this galaxy was not visible. As a first step, I identified the pairs of stars indicated with blue ellipses on the image above. Observing carefully the area where UGCA 334 should be visible the result was unfruitful. Some ODM methods state that this galaxy, assuming that the magnitude value of 12.5 given by some sources is accurate, should be visible through an 8-inch telescope under a 6.6 limiting magnitude sky, being 107 the optimum magnification.

UGCA 334 and the core of the galaxy cluster ACO 3544 (green +) appear close to each
other in projection on the sky. 
Picture from AladinLite. Digitized Sky Survey - STScI/NASA, Colored & Healpixed by CDS
Applying higher magnification with one of my eyepieces (106x), and observing with averted vision under a dark sky, the galaxy could be barely glimpsed at times. It is a challenging object for a telescope of this size, so you need to stay at the eyepiece for some minutes and avoid even the polluted light of the site where you are observing from, by covering your head with a black cover. Try to be patient, even if the view is not clear you should see a very faint, small, very elongated, and smooth nebulosity. A ghostly image of a galaxy that looks like a lonely object in the southern sky.

The view of this galaxy with even higher magnification (148x) is similar, appearing smooth and elongated. It is a very challenging object, at least from my experience during that observing night.