Celestial sphere = imaginary rotating sphere (got it)
Meridian = ???? no idea
celestial poles = point on the celestial sphere above arctic ocean (North) and antarctica (South)??
The reason for this is I'm going to attempt polar aligning my scope for tracking! I've been trying to read up on it, but some sites have me confused. Why do they have to use big words like 'meridian' and 'celestial polse'..? Why can't they just say, "point your scope at this star!!" Done!
The meridian is simply a line drawn between the north and south celestial poles and which passes through the point directly above the observer (you). That point is called the zenith.
We in the southern hemisphere cannot see the north celestial pole so we have to work out where it is, even though it's below the horizon. While it sounds hard, it's not. Drawing an imaginary line between the south celestial pole and the point directly above you and then extending the line to the northern horizon shows you the direction of the north celestial pole.
Now the poles: Firstly, ignore the tilt of the Earth relative to the Sun. The Earth, in a general sense, is static relative to the stars - other than its spinning around once a day. This means that the stars (not the Sun or its planets) trundle around the sky as we see it on a regular basis and pretty much in the same position. Because the Earth does spin and because the Earth does do a lap of the Sun once a year it means that the stars appear to move in the sky when seen from any point on the planet. As a result of this the poles - which you correctly describe as being points extended from the north and south poles of the Earth - do not appear to move. They do, but not noticeably, as the Earth 'wobbles' a bit. This is known as 'precession' but it takes some 20 odd thousand years to complete a circuit and is ignorable in most peoples' lifetimes.
Should you have difficulty with the concept then temporarily turn yourself into a 'flat earth' believer, but with a twist. Imagine Earth being a disc with some of us living on one side and the rest on the other. Assuming that said disc did not move relative to the stars then observers on one side of the disc would not see the same stars as those on the other side.
Of course the Earth is a sphere, so the point from which you observe the sky will (and does) affect what you can see and where you see it.
Thanks Eric! Going through it now! Weird how I don't get reading long posts or books about astronomy...but in school/uni, try reading more than a page of a textbook, and ZZZzzzzzzzzz....
No, I'm still awake! However, still a little confused. Once I have my scope polar aligned, what can I move (which axis) to look at, for example, Jupiter or Saturn etc... And what is a polar scope? On my RA axis beam thingy, there is a cap on the end which I can take off...and it's possible to look through from one end to the other. Is that the Polar scope?
That space in the RA axis is for a 'polar scope'. The polar scopes I know of are mainly for the northern hemisphere and show where the star Polaris should be placed to make your mount polar aligned (it's supposed to save you time). Although I think I have seen some with four stars that help you align to the south celestial pole.
The idea behind polar aligning is that once the mount is aligned and you switch a drive motor on the mount should track an object across the sky without you having to make any further adjustments to the direction the scope is pointing.
To point at a object you will need to move the mount on both axes. The RA moves in the east-west direction, the Dec in the north-south direction.
Djv Find yourself a local astronomy club Or better still Come up to Cambroon and we will give you some instructions for FREE,
I am here seven days a week, so if you feel like a trip up the coast I would be happy to help you out.
Cheers astroron
Thanks for the offer astroron! I dunno when I could get there, though. And there are no clubs here...only my good mate, Phil! Wealth of knowledge there!
Ok, I'm FAIRLY sure I found octans...the old 4 star grouping that is...although, they are fairly faint through the ol' 15x 70s. I wanted to get the scope out tonight to check out the moon, but it's waaaay too bright!! My eyes were watering just looking at it through the binos. Which filter do I need for the moon? I have a UV/IR one coming...is that what I need?
Oh..and here, I think this question will clarify my problem.
* Once my scope is polar aligned, what can i do that will put me OFF alignment? (besides moving the tripod, bumping the scope etc...). Will moving the scope in either axis ruin my polar alignment???
DJVege, I made this pic up a while ago for just such ocassions.
Once you've found the South Celestial Pole, it's easy to find again.
If you're having trouble finding it with you big binocs, there's something strange going on because it's easily found in 7 x 50 + smaller.
You need a 'Moon Filter' ( point 96, Neutral Density) to see the moon without being 'blinded'. Although there are some who do not like using them. They like it 'naked' so to speak.
Once your t'scope mount is Polar aligned, you can move it anywhere with the controls, as long as you don't move the mount.
HTH. L.
Once my scope is polar aligned, what can i do that will put me OFF alignment? (besides moving the tripod, bumping the scope etc...). Will moving the scope in either axis ruin my polar alignment???
What?? Ok, now I'm confused! I was fairly sure I found it, but now you say it won't fit in 15x 70s FOV....??? I thought it fit quite easily in my FOV..??? Maaan!!! What the hell was I lookin at then? It even looked just like your image, RAJAH235! (Flipped of course).
I'm going to try again, tonight. Wonder if my Digital Camera will capture anything. I'll try and take a photo for you guys.
It was difficult last night as well, because the damn moon was so bright!!! Is the octans box always fairly faint (if I saw it last night, that is).
OK! haha, I definitely DIDN'T find the octans box the night before!! rofl! I found it tonight though!! It only just fits in my 15x 70's FOV.
That was the only good thing about tonight! I couldn't put the scope on the octans box....I don't know how to use the polar scope in the RA tube. And my understanding of polar aligning is fuzzy to say the least. Also, where I am (backyard) it's fairly crap for polar aligning because the house and trees are in the way of the octans box. (Actually, the box lies a bit in between the house and the trees). AND the moon was WAAY to bright!!! It was if someone was shining a mini floodlight into my backyard!
Finally, my finderscope is crap. Or I don't know how to use it, which is a high possibility seeing as I'm a n00b. It won't focus...stars are always blurry. AND the finderscope ALWAYS gets into positions that make it difficult for me to look through it.
DJVege.
FWIW. As a guide, the Southern Cross (Crux) is 6 deg x 4 deg & the smallest of all constellations in area.
Have made up a slightly newer version of SCP finder showing approximate/average fields of view of binocs.
The finder should be adjustable for focus usually by the objective lens.
HTH. L.
Thanks for that. Yep, that's definitely what I saw.
Anyone know how to use the polar axis scope? Mine has some markings on it, and i can't see through it....? How do I know if it's on the octans box or SCP or anything?
I try to focus the finderscope, but the only thing that comes in and out of focus are the crosshairs.
Confused...Astronomical concepts???
I've been trying to read up on it, but some sites have me confused. Why do they have to use big words like 'meridian' and 'celestial polse'..? Why can't they just say, "point your scope at this star!!" Done! 
And there are no clubs here...only my good mate, Phil! Wealth of knowledge there! 
It only just fits in my 15x 70's FOV. 
