#1  
Old 22-04-2009, 02:39 PM
beefking (Nathan)
Registered User

beefking is offline
 
Join Date: Feb 2009
Location: Brisbane
Posts: 54
backyard obs 21/04/09

Hi all, this is just a brief rundown of some objects I viewed last night from my backyard with my 12" dob. It's reasonably dark, but there are a few streetlights that need to be avoided and a good degree of spill light from neighbour's houses.

I looked at a lot of the usual suspects, but the standouts/new ones were:

Jewel Box - I really noticed the colours this time, which reminded me to have a look at the carbon star near Beta Crux - (DY crucis) extremely red, and looked great contrasted with Mimosa.

M104 - tracked down for the first time last night. I thought I could pick up in my 9x63 binoculars as well. The well-known shape of the galaxy was easy to pick up, but the dust lane only showed itself occasionally.

A planetary in Vela and one in Pyxis - I had my copy of sky atlas 2000.0 out, and looking around Vela I picked up NGC 2818 as looking interesting.
I thought I'd go for nearby NGC 2792 first, as it is close to Gamma Velorum. It looked small on the chart, and I honestly didn't expect to find it, but about 20 minutes later, there it was, barely visible as a dot. The max magnification I can do at the moment is 167x, and even at that it was tiny, but clearly non-stellar. Stellarium gives it as mag. 14, so I'm kind of surprised I could find it from my backyard.

Encouraged by that victory, I thought I'd have a go at NGC 2818 - it looked more remote from bright stars so I assumed it would be harder to find. It's a pretty cool object - a cluster and planetary similar to M46, but the cluster and planetary are much closer in size, and the planetary did not have a well defined edge. It's an interesting object and I recommend it.

M83 - After that win, I thought I'd have a go at M83, which has always looked so far away from handy sign posts that it would be kind of impossible. It wasn't and I was rewarded with a large, round soft glow with a stellar centre. There seemed to be hints of more detail just out of reach, but with the amount of stray light flying around... well, I think it will be worth finding from a dark site.

this star-hopping thing, it's not so hard after all
Reply With Quote
  #2  
Old 22-04-2009, 04:01 PM
ngcles's Avatar
ngcles
The Observologist

ngcles is offline
 
Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,664
Hi Beefking,

Quote:
Originally Posted by beefking View Post

... Encouraged by that victory, I thought I'd have a go at NGC 2818 - it looked more remote from bright stars so I assumed it would be harder to find. It's a pretty cool object - a cluster and planetary similar to M46, but the cluster and planetary are much closer in size, and the planetary did not have a well defined edge. It's an interesting object and I recommend it.

M83 - After that win, I thought I'd have a go at M83, which has always looked so far away from handy sign posts that it would be kind of impossible. It wasn't and I was rewarded with a large, round soft glow with a stellar centre. There seemed to be hints of more detail just out of reach, but with the amount of stray light flying around... well, I think it will be worth finding from a dark site.

this star-hopping thing, it's not so hard after all
Interesting report -- thanks for letting us all know how you went.

NGC 2818 is a wonderful PNe -- one of my summer/autumn favourites that rewards both a dark site and really good seeing.

First, this is how it looked in my old 10" in 1996:

x138 21' TF. Mag 8.2 Size 8'. Quite a small cluster which is no more than 10' diameter. The 4 brightest *s seem to mark boundaries, and a mag 11 * in the centre. scattering of maybe 50 *s mag 11.5 to threshold and milkiness in the centre. Mod range in brightness, More faint *s in the S end. On the outer halo in NW corner is NGC 2818A, and associated PNe.NGC 2818A Mag 11.8 Size 84" Easily visible at x86 without filtration. sort of "U" shaped and open to the NE. Roudish, unevenly lit. S side is distinctly brightest. Bright spot or stellaring there. Dark area (ie inside the "U", intrudes from the NE toward centre. A very pleasing object. No central * is evident. Diffuse edges.

and here is an observation I made of it with my 18" in 2006 from Bargo under a "nearly-dark" sky with good seeing:

NGC 2818A Planetary Nebula
RA: 09h 16m 01.5s Dec: -36° 37' 37"
Mag: 13.0 (P) Size: 93.0"x55.0" Class: 3b
Mag C. Star: 19.4 R.V.: ---

12mm, 9mm & 7mm Naglers, x185, x247 x317, (Unfiltered, UHC & OIII)

This is the first time I've seen this PNe in this aperture and it didn't disappoint -- a very interesting and unusual PNe. The brighter areas look like a pair of longish butterfly wings without the butterfly body in the centre -- longish opposing mirrored triangles with the long axis in PA 90. Each long triangle is about 30" long and 10" wide at the widest and the N one is slightly the weaker in brightness and definition. The short sides of the triangle are the best defined but the two long Hypotenuse much less defined on their edges. An area around this is very weakly nebulous out to 60" diameter. Moderately bright. Good response to OIII and UHC. Some bluish/smoky bluish colouration Best at x247 with 9mm T1 Nagler.

where it showed much of the detail visible in this image here:

http://www.capella-observatory.com/I...s/NGC2818A.htm


12" will show undoubted spiral structure in M83 -- keep trying. I've seen the arms in 6" at a top-notch site and others with better eyes have done it in yet smaller 'scopes.

Re star-hopping -- yep it is a skill. Like riding a bike it takes a while to master but is a skill that is never forgotten.


Best,

Les D
Reply With Quote
  #3  
Old 22-04-2009, 08:38 PM
beefking (Nathan)
Registered User

beefking is offline
 
Join Date: Feb 2009
Location: Brisbane
Posts: 54
Thanks for the comments Les. I'm heading out of town with the scope on the weekend, and those objects are on my list for sure. 2818 definitely warrants a look under better conditions.
Reply With Quote
  #4  
Old 23-04-2009, 08:50 AM
Rob_K
Registered User

Rob_K is offline
 
Join Date: Oct 2006
Location: Bright, Vic, Australia
Posts: 2,158
Nice report Nathan! Hope to hear more of your viewing - keep going with the planetary nebulae as your 12" will reveal lots more goodies yet!

Cheers -
Reply With Quote
  #5  
Old 23-04-2009, 09:19 AM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Gerringong
Posts: 8,532
Looks like you are well on the way, Nathan! Thanks for the report. I love the Jewel Box. Tell us what you see when you really get under dark skies.
Reply With Quote
  #6  
Old 26-04-2009, 06:45 AM
Davekyn's Avatar
Davekyn (David)
Loves Staring Into Space!

Davekyn is offline
 
Join Date: Jul 2007
Location: Hervey Bay QLD Au
Posts: 493
Read up on NCG2818...going to check this one out for sure. Thanks.
Reply With Quote
  #7  
Old 21-05-2009, 05:27 PM
beefking (Nathan)
Registered User

beefking is offline
 
Join Date: Feb 2009
Location: Brisbane
Posts: 54
backyard obs 19/05/09

Had another session with my 12" dob, in the backyard on Tuesday night. There was a bit of annoying light from inside the house occasionally, but on the whole it was a good few hours.

It was my first real session with my new 6mm Ethos and 31mm T5 Nagler.

Started off with saturn, and finally got a good look at it through the ethos. looked great, and there were a few moments of excellent clarity.

My next stop was Eta Carina, which is incredible at the best of times. I put in the 31T5, and the view was astonishing. A lot of attention is focussed on the keyhole and surrounds of Eta Carina itself, but the nebula to the south looked like a curtain billowing in the breeze.

Conversely, at higher powers the section of nebula to the north-west of the keyhole looked lumpy and kind of foreboding. Through the 6mm, the field is small enough that motion is obvious - the nebula looked like a storm cloud drifting overhead.

I moved on briefly to DY Crucis - it's quickly becoming a favourite.

Omega Centauri was swarming with stars, the footprint effect in the middle was obvious.

Next up was the NGC 3132, the eight-burst nebula. It was blinking in and out at 63x, but there were hints of structure at 166x.

Followed it up with NGC 3201 in Vela. This is a pretty small globular. partially resolved at 166x, with a squarish shape.

Had a quick look at NGC 2818, and it is an interesting object.

I had a good look at NGC4945 and NGC4976 in Centaurus. 4945 was large, obvious and elongated, however only the core of 4976 was easily visible. I was viewing with a fair bit of stray light, so the view was not as good as it could have been .

I had a quick look in Virgo, at M61 and NGC4666. M61 was easy to find - 13 Vir, on to 16Vir, then to 17Vir, then half way back to 16Vir. I picked up the core and a circular glow, but couldn't really pick out any spirals.

NGC4666 is close to Gamma Virgo, or Porrima, though I originally thought I'd found NGC4653. The scale of SkyAtlas is a bit deceiving sometimes, and it wasn't until I'd checked against Starry Night that I identified 4666. Anyway, it was an elongated glow, with a bit of central brightening. I will have to have a better look, because it wasn't too hard to find. I want to find 4653 and 4668 as well, as they are shown very close by.

I moved on to M83, and picked up hints of the spirals. My final object was NGC 3918, the blue planetary, and blow me down, it's blue. not especially strongly, but I'm pretty sure I picked up colour.

it was a good night, and a good practice run for next weekend.
Reply With Quote
  #8  
Old 21-05-2009, 08:11 PM
ngcles's Avatar
ngcles
The Observologist

ngcles is offline
 
Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,664
Good report.

Hi Nathan,

A very interesting report (19th May) mate and going on the news tonight, you might be the only person in QLD who has a clear sky!

Good to see you had a go at such a wide variety of objects. I'd be keeping at M61 -- a 12" will show a patient observer some hints of spiral structure. By no means will it jump out at you but have a photo at the eyepiece so you can see the orientation of the structure. Most notably, M61 is curious because the arms appear "broken" -- some parts of the arms, rather than being in a curving sweep are in segments like they are being bent around a 50c piece.

NGC 3201 is a very underrated GC -- it is bright, nearby, uncompressed and comparatively easy to resolve. I think it looks similar to M55, only the field around M55 is a lot less rich.

Compared to NGC 4945, NGC 4976 is a much smaller galaxy but has somewhat better surface brightness. It should therefore look comparatively small to -45 anyway. One clear night, why not have a crack at the close-by, small faint edge-on NGC 4945A?

It is not too hard to see in 12" (I've seen it in suburban skies). It is only 17 arc-minutes SE of the dead centre of NGC 4945, it has a 9th mag star embedded at the northern end and is also near a small group of 11th - 13th magnitude stars.

Keep up the good work!


Best,

Les D
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 07:21 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement