ICEINSPACE
Member Login
Most Read Articles
Moon Phase
CURRENT MOON Waxing Crescent
13.4%
The Sun Now
Time Zones
Sydney
5:58 am
Perth
3:58 am
Auckland*
8:58 am
New York*
3:58 pm
Paris*
9:58 pm
GMT
7:58 pm




Beginners Guide to Finding the SCP - by a Beginner
Submitted: Tuesday, 26th February 2008 by Chris Turton

After spending a LOT of clear sky time trying to get the hang of drift aligning and also trying to figure out which way is which in the scope and finder, I thought I might have a go at actually targeting the South Celestial Pole (SCP) using my shiny new 11x70 Binoculars, figure out where it is, set the scope in the right direction and therefore eliminate the drift when using a motor drive on the RA axis. Something in my initial setup didn’t feel right and as a consequence I have come up with this star hopping method to help any newbies out there get their Equatorial mount set up quickly and (hopefully) accurately. Without knowing what you are actually LOOKING for, it becomes extremely frustrating to try and find this elusive beast. I have combined some sage advice from the experts on IceInSpace and my own observations to come up with a solution.

Please note, these instructions assume the following:

  1. You have either some binoculars or other magnifying device like a finderscope (5x30) or better, to zero in on the areas listed.
  2. That you can actually SEE stars and constellations in the direction of the SCP, or most importantly Archenar, Crux and Alpha Centauri. ie no clouds and little light pollution.
  3. You know how to adjust your Latitude (altitude) and Declination settings on your mount.
  4. You are physically capable of moving your mount around.
  5. You want to get polar aligned fast.
  6. Your brain hurts trying to figure out drift aligning. (think standing in back yard with arms flapping around looking like a goose.)
  7. You won’t hold me responsible if this doesn’t work for you.

OK, with reference to the diagrams below, here we go.

Method
  1. Adjust (if possible) the tripod so that one of the tripod legs points roughly south (using a compass) and that the mount is lined up along this tripod leg. I normally set the south pointing leg to around 168° which is True South for Sydney. Make sure your tripod is roughly level.
  2. Set your telescope mount to 90° Declination (this is the direction of the SCP) and your scope’s tube should be in line with the south pointing leg.
  3. Find Archenar (labeled 1 in image 1) in the sky, this will be your starting point.
  4. Look towards Crux and Alpha/Beta Centauri. Draw an imaginary line (YELLOW) in the sky between Alpha Centauri and Archenar, you will notice that this line passes close to a star in the constellation of Hydrus (Beta Hydrus – marked as 2) as well as the Small Magellanic Cloud (SMC – if visible). Alpha, Beta and Gamma in Hydrus form a triangle that is “almost” an equilateral (equal sided) one in the sky and Beta Hydrus has a small star off to one side which helps you know you are on the right one.
  5. From Beta Hydrus (point 2) look toward the Southern Cross (Crux) and draw an imaginary line (GREEN) between Beta Hydrus and Acrux (the star on the bottom of the cross, furthest away from the others). This line passes very close to the SCP, but never fear, we will get there soon…
  6. Using the imaginary green line and starting from Beta Hydrus, move slowly along this line using your finderscope or binoculars and you will quickly see a group of three stars arranged a little like the hands of a clock pointing to 5 minutes past 6. These are Gamma1, Gamma2 and Gamma3 of Octans constellation (image 2 & point 3). Keep a note of the distance between Beta Hydrus and these stars, you are now going to double this distance along this line to find Sigma Octanis and friends.
  7. From Gamma1-3 Octanis, keep going along the green line towards Acrux the same distance and you should come across 3 brightish stars arranged in a triangle (point 4) these are Sigma Octanis on top, Chi and Tau Octanis. We are now VERY close to the SCP. Sigma Octanis has a small star off to one side nearby.
  8. Create and imaginary equilateral triangle using Tau and Chi Octanis that encloses Sigma Octanis (attachment 3). The point of this new triangle is the SCP.
  9. Adjust your scope so that this SCP point is centred in the finderscope by adjusting the altitude and orientation (east / west) of the tripod so that the finderscope points at the SCP.
  10.  Test your scope’s alignment by targeting an object, engage the RA motor (or manually find using RA axis only after a star has drifted off) and see if you have sorted out your alignment once and for all…..
  11. Once you get to know where the SCP is you should be able to point the scope fairly quickly in future sessions.


See how you go, if in doubt, do what works for you. Please forgive any errors I may have made.

image001.jpg

Click to Enlarge
Image 1
image003.jpg

Click to Enlarge
Image 2
image005.jpg

Click to Enlarge
Image 3
Article by Chris Turton (Screwdriverone). Discuss this article on the IceInSpace Forum.
Advertisement
Meade Instruments
Advertisement
Atik 16200
Advertisement
Bintel
Advertisement
Tasco Australia
Advertisement
FLI Cameras and Imaging Accessories
Advertisement
SkyWatcher Star Discovery
Advertisement
Lunatico Astronomical
Advertisement
OzScopes Authorised Dealer
Advertisement
Astronomy and Electronics Centre
Advertisement
ICEINSPACE
AUSTRALIAN AMATEUR ASTRONOMY
Copyright © 2004-2017 ICEINSPACE.
All rights reserved.