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mental4astro
28-09-2009, 12:18 PM
Hi all,

Answering Lismore Bloke's call to arms', I thought to put down the observing session done on Friday 25'th of September.

Done from Sydney's Eastern Suburds, I aim to show what can be seen in the sky, even during the Moon's first Quarter.

I also hope to enthuse new comers to Astronomy. Peter has only had his 8" scope for a couple of years, is still getting his bearings and realise the full potential of it.

Equipment: 8" GSO f/6 dob, 17.5" Odssey II f/4.5 dob, various EPs, #80A blue colour filter, Lumicon Nebula filter, and 10X50 binos. The binos are invaluble in a light polluted enviroment. Just won't find most objects otherwise, except if using digital setting circles.

We were originally to set up from a school's oval, but the wind proved too strong & cold. Moved viewing session to my backyard, nearby & offered shelter from the wind.

First object was Jupiter's Great Red Spot. Peter hadn't seen it. The GRS can prove illusive to spot, as it is not cherry red in colour, rather it is pale, and the glare of the planet can wash it out if you don't know what to look for. We used the blue filter on a 1.25" EP, and there it was, bang in the middle of the disk on the southern cloud band. The blue filter made it an obvious soft orange colour breaking up the southern cloud belt which was now darker in colour. Seeing was aweful that night, so any higher power over 150X was not possible. Still this offered the occasional glimpse of swirls & festoons of detail.

We then had a go at M4. With the moon located close to the head of Scorpio, it was ney impossible to view it. After much effort, we just caught a glimpse of it as a faint streak of cloudiness, which M4 is famous for.

We then moved away from the moon & had a go at the globular cluster NGC 6752 in Pavo. Spectacular. It has a dense core with a mass of stars radiating out. Its stars vary in brightness and colour, give a 'jewel encrusted' feel to it. Though the Odyssey showed more stars, the 8"'s image was more pleasing as its slower focal ratio made for a darker backgound continuum, improving contrast.

Next was 47 Tuc. Amazing in any scope. It seemed to leap out of the 2" GSO 30mm 68degree EP.

I then tried to track down the Grus quartet of galaxied, NGC 7531/52/82 & 99. I had seen their obvious galactic cloudiness from Sydney in both the 8" & the 17.5", but this time with the Moon it was impossible to make out anything.

Then had a go for the beautiful galaxy NGC 253. Though not as detailed even when viewing from town without the moon, it was an obvious oval streak in both scopes. Didn't need to employ the giggling technique with this one. We returned to it after the dark of the night started, and it began to reveal some faint mottled detail in the 17.5"

Had a go then for another galaxy, NGC 55. A pencil thin streak of light which needed the scope to be 'giggled' or moved about, to be able to spot clearly at first. I'm not too sure how this giggling technique works, but it does with the faint fuzzies. The 8" showed it a little more clearly on moving with its better contrast.

Peter chanced on the Tarantula Nebula with a scan of the sky through the 8". Silly me knocked it out of view and we had a hell of a time finding it again, even with the binos, as there are no bright stars to help with the star hopping. But we did. The Lumicon filter helped bring out some detail, and revealed more nebulosity surrounding the Tarantula within the Large Magellanic Cloud.

I also had a go at tracking down Uranus. Again the binos came into their own as where it is in the sky there are few bright stars, especially with the moon about. It was my second viewing of Uranus & Peter's first. Well worth the effort with its emerald/lime green colour & small but obvious disk. Uranus is easily visible in the binoculars, just need a Uranus/Neptune map to track down. Neptune is also visible, being located close to Jupiter at the moment. But need a scope to view it as well as the map, with its brilliant deep blue colour distinguishing it from the surrounding stars.

It was 11pm by this time. Tried for the galaxy NGC 300, but weariness got the better of us, so we packed up.

I hope this encourages fellow astro junkies to take out their scopes while the moon is on its smaller phases. Try to keep the moon behind you, be patient & use binos. Peter's scope uses a 50mm right angle correct image finder & my Odyssey had its new 3" reflector finder with a red dot finder mounted on it. Without the binos to navigate first we would not have found what we had. I always use them in the big smoke.

Mental.

goober
28-09-2009, 12:22 PM
Great stuff.

ngcles
28-09-2009, 01:03 PM
Hi Alexander & All,

Thanks for taking the time to post your observations -- it was very enjoyable to read.

Re Jupiter's GRS, it has certainly changed colour over the years. I remember back in the 1970s when it was a strong almost brick red colour and it stood out like carrot in an omelette. Very easy to distinguish from its surroundings. Nowadays, particularly when it is close to the limb, I seem to find it more easily by finding the hollow it sits in as the SEB appears to deviate around it . I'd describe the colour nowadays as salmon-pink when it is at its "best" or fawn -- fawn/greyish.

Went to a talk the other night and learned from Anthony Wesley that the GRS is also shrinking -- which was something I didn't know or at least hadn't noticed over the years. Apparently over the last 50-odd years it has shrunk about 30% and is also more round than it used to be (used to be oval).

Re NGC 7552, -89, -90, -99 these are comparatively good targets from suburbia because they generally have good surface-brightness.

NGC 300 is tough from suburbia because it has such low SB and even worse is NGC 247. From a proper dark site both are visible in hand-held binoculars but 247 in particular is an extremely testy thing from suburbia.

Next time you have a go at Uranus & Neptune with the 45cm, try spotting some of the moons. I remember a friend of mine with 50cm had quite a queue at his 'scope one open night at Sutherland Astronomical Soc to see 4 Uranian moons. I've seen Triton (Neptune's only major moon) many times in my 46cm -- even from suburbia. It is about mag 13.5. Once you've spotted Neptune (or Uranus), crank up the magnification to x250 or more to see what you can of the moons. There is a site somewhere that gives an ephemeris but I just can't find it at the minute.


Best,

Les D

DavidU
28-09-2009, 01:40 PM
Yes, this is how I remember it.

Lismore Bloke
28-09-2009, 04:53 PM
Hi Alexander and Peter,
You did so well seeing some of those objects from Sydney suburbia with the moon up. I too found objects in the opposite part of the sky to the moon much easier to spot than the area around Scorpio. I found the globulars were best in a moonlit sky. Hunting double stars is also well worth doing. It just means looking for targets with a high surface brightness that will work on the night. Have you tried the filter on any planetaries, eg NGC7009? I must try a blue filter on Jupiter, I think I have an old photographic one somewhere. Good to see some observers not being put off by light pollution or the moon. Cheers, Paul.

Astro78
30-09-2009, 05:01 PM
Great account there Mental.

Thanks for the fire up - it's been a while since I've pulled the old girl out.

Appetite primed.

Blackant
30-09-2009, 08:41 PM
Thanks mental, great account :)

telecasterguru
30-09-2009, 09:30 PM
Alexander,
Fabulous run down on your night out.
I also have trouble finding what I am looking for as I also live in the Eastern Suburbs. My backyard is a 1mx1m concrete block but that will not deter me, although at times it makes it difficult to swing the dob around.
The one thing I will never do is give up. There is always something to find and look at.
When are you next going out? I would love to bring my scopes around.

Frank

mental4astro
30-09-2009, 10:01 PM
Hi all,

Thanks for the compliments. This recent sequence of threads & posts in this forum helped spur me to ask for help to improve my skills too. Les, mate, you are a wealth of info & you are generous with it too. Thanks.

I have two sessions book marked for this month. The first for the 17'th at Katoomba. Hopefully the airfield will be available. The second is planned for the 23'rd at Randwick Girls' High School, see the following:

http://www.iceinspace.com.au/forum/showpost.php?p=497847&postcount=31

Peter is looking for a few more scopes to help out. Let him know if you can help. I'm looking at bringing at least a couple of scopes.

I will be chasing down a few more planetary nebulae. Only tracked down one from Sydney. See how we go.