Centaurus A from urban site?

Lee · #1 17-07-2006, 08:37 AM

Hi all....

Well, after the rain cleared yesterday, I finally got to dust off the Dob and do some stargazing to make the most of a late rising moon- the rain was my own fault, I picked up a new 20mm TV Plossl on Wednesday last week....

I was showing my partner some of the brighter DSO's around the place, started in Scorpius with M4, M80 and M19. I very quickly worked out the TV EP blows the Andrews 2-incher away.... I now need a new low-mag EP! Found the Blue Planetary off of Crux (very cool!), then showed off the Jewel Box and Omega-centauri.

But my objective for the night was to spot a galaxy, so I chased Centaurus A.... my Starry Night chart didn't print properly, and cropped off omega centauri, so I had to use a really low mag chart, which hindered me a lot, and ended up wondering if I saw it at all - I THOUGHT I saw a VERY faint fuzzy with a hint of a less-fuzzy patch in the middle...

Does anyone observe this galaxy from a less than very-dark site with an 8" Newt??? We were dark adapted, and could see the milky way beginning to appear also - is this darkness suitable???
Will be trying again soon, thats for sure, better star charts are made and ready....

Clear skies guys (and gals)

CosMos (Rich) · #2 17-07-2006, 09:20 AM

I used to live 20 minutes walk from Auckland City and sky pollution was dreadful...no milky way at all but still managed to pull in Cen. A Took a couple of minutes on the area to see it. Was using 20cm f6.8 scope.

Rich

astrogeek (Leon) · #3 17-07-2006, 09:27 AM

Yeah, same here. I managed to catch it in Melbourne with an 8". Very, Very faint though

Lee · #4 17-07-2006, 09:38 AM

Thanks guys.... Will have another crack this week armed with some better charts. Looking at my wide view charts, there are two little 4 star asterisms in similar areas out from omega centauri that I now think I may have been confusing.
I think I can feel a bead of sweat on my brow - might be aperture fever.....

CosMos (Rich) · #5 17-07-2006, 09:44 AM

The following (365 KB) map may be helpful. A line from beta Centauri through epsilon then omega Cen and onwards to what I call the "Golden Triangle" shown in map. Lovely group of orange stars. Nice pair of white stars below and left are obvious and rather nice together.

See: http://homepages.slingshot.co.nz/~rlamoss

ving (David) · #6 17-07-2006, 10:13 AM

hiya lee!

I live in campbelltown so i am guessing that my skies are similar or worse than yours (proabably the later) and i use the exact same scope as what you have...

cent A shows quite well in my scope as a large fuzzy blob disected thru the middle with its dark lane so this is what you should be seeing too. I usually have to take a few mins to find her as i dont really have any guide stars to help me tho. so did you see the hamburger?

Lee · #7 17-07-2006, 10:38 AM

Quote:

Originally Posted by ving

cent A shows quite well in my scope as a large fuzzy blob disected thru the middle with its dark lane so this is what you should be seeing too. I usually have to take a few mins to find her as i dont really have any guide stars to help me tho. so did you see the hamburger?

With the "eye of faith" I thought I could see it! With a decent chart now I'll know exactly where to look.... haven't seen a galaxy DSO yet, so am looking forward to it....

CosMos (Rich) · #8 17-07-2006, 11:15 AM

Have attached smaller map.

Lee · #9 17-07-2006, 11:39 AM

Thanks CosMos... will give it a go....

Starkler (Geoff) · #10 17-07-2006, 06:19 PM

While in Centaurus, also have a look for galaxy NGC4945, its quite large and cigar shaped.
Ngc5108 should be an easy catch as its fairly small in size and able to be seen with a higher magnification.

mickoking · #11 17-07-2006, 06:41 PM

G,day Lee

I have seen Centaurus A with a 200mm Dob from a suburban site (closer to Perth CBD than where I live now). While quite faint I could observe the two halves of this object. At my current location on Perths urban frindge I have seen Centaurus A with a 80mm refractor and even noticed structure and a couple of foreground stars with averted vision. With a 300mm Dob the galaxy looks like a hamburger

acropolite (Phil) · #12 17-07-2006, 07:01 PM

I have seen the split in Centaurus A from my site here in Tassie with an 8 inch LX90. Light pollution here I would consider as light to moderate (I can see 47Tuc LMC & SMC naked eye) and the image I saw was easily recognisable.

Lee · #13 17-07-2006, 08:06 PM

Thanks for your helpful replies guys.... I'm really thinking I was looking in the wrong place now!

mickoking · #14 17-07-2006, 09:05 PM

Quote:

Originally Posted by plasmodium

Thanks for your helpful replies guys.... I'm really thinking I was looking in the wrong place now!

Centaurus A is almost 5 degrees due north of Omega Centauri.

CosMos (Rich) · #15 18-07-2006, 07:15 AM

When I was on the spot where Centaurus A should be, I noticed the dark lane first of all before the gas itself. It showed up slightly darker than the background sky glow.

CosMos (Rich) · #16 18-07-2006, 07:23 AM

Lee, Here is a finder chart for the elusive beast

CosMos (Rich) · #17 18-07-2006, 07:29 AM

Me again...someone mentioned NGC 4945.

mickoking · #18 18-07-2006, 12:52 PM

NGC 4976 is close to 4945. It is smaller but brighter.

Lee · #19 13-08-2006, 10:41 PM

Got it!
Armed with a moon free evening, some good finder charts - heck, I've looked for it 4 times now, I know my way around that area pretty well!
Found a faint fuzzy in the right spot - I can say that much.... Can't expect too much from a suburban back yard though. Taking the dob on a work trip to a truly dark site (plan these work trips for new moons

) in two weeks - will check the difference then.
My first extra-galactic light!

ballaratdragons (Ken) · #20 13-08-2006, 11:03 PM

Excellent Lee. Galaxies are more exciting to me coz they are just that bit harder to find and see. And look great! But my 12" in Dark sky helps too.

You'll have a blast at a dark sky site.