SCP direction table

[Sconesbie (Scott)]

Good morning. I have been doing a bit of searching on how to set up my telescope to the south celestial pole before I start using it. One site says (after preliminary setting up):

-once found south using compass (magnetic south) align scope with compass to have pointing in same direction.

-when done, turn scope to either east or west according to the SCP table. Well, Tasmania was left off the table on their site and I can't find one anywhere.

-set altitude on scope according to latitude


So, I am asking for some help here.

-once I have a table, I can use my compass to turn the scope either east or west to start sky watching.

-do I then turn the RA to match the co-ordinates for a specific star or planet according to star charts once all that has been done? Ie 46 deg, 45 min, 23 sec?

I hope all that makes sense.

Thank you.

[rogerco (Roger)]

There are probably other solutions but one is to buy a 1:25000 topo map and it will have the magnetic variation on the data panel.

[Sconesbie (Scott)]

Thanks roger. Is there a table of co-ordinates that exists? The web page said turn east or west according to the "table" once you find south. The only available co-rods were for mainland capitals.

[brisen (Brian)]

Hi Scott

This website will help. http://magnetic-declination.com/Australia/ Simply zoom in to where you are and click on the map. It will tell you what the deviation is. It should be around 14 degrees East for Tasmania.

Brian

[rogerco (Roger)]

Putting "magnetic variation for tasmania" into Google got this site amongst others.

http://www.ourairports.com/airports/...ilot-info.html

As the other person say Hobart 14.5 degrees. What the topo map will tell you as well is how much it varies each year, its not a fixed thing.

[mithrandir (Andrew)]

Go to the source: http://www.ga.gov.au/oracle/geomag/agrfform.jsp

Requested: Latitude -41o 22' 00", Longitude 147o 3' 00", Elevation 0 km, Date 2014/01/1
Calculated: Latitude -41.3667o, Longitude +147.0500o, Elevation 0.00 km, Epoch 2014.0000

Magnetic Field Components

D = 13.944 deg

There is a declination app for iOS. I don't know about Android.

[acropolite (Phil)]

Scott, the easiest way to find true south is to use the Solar Noon method. All you need is to calculate the exact time or Solar noon and place a vertical stick in your viewing area, the shadow will then be true south. Mark true south on something permanent, a brick or paver is ideal.
More info in this thread

[Sconesbie (Scott)]

Thanks for the help. I guess it pays to know what to type in. I would never have looked at an airport link. I'm getting there slowly I think. Heaps more to learn. I'm making notes as I go so I can understand better.

[Sconesbie (Scott)]

So, now I've got that sorted, I have another question.

I'm at true south now (theoretically speaking), should the DEC and RA settings be on 0? That way when I'm searching for something via charts and co-ordinates, it should be close to being spot on?

[rogerco (Roger)]

You might have to do a bit of reading, I don't use them but I think you set the telescope to point to a particular star and then zero the dials, if you know any star and can find then point at that and set the dials to the coordinates of that start.

[mithrandir (Andrew)]

Originally Posted by Sconesbie

So, now I've got that sorted, I have another question.

I'm at true south now (theoretically speaking), should the DEC and RA settings be on 0? That way when I'm searching for something via charts and co-ordinates, it should be close to being spot on?

If the scope is pointed at the SCP the declination is -90 so you could set that circle.
RA is different. At the poles all the meridians of RA meet so you can't set the RA circle unless you know the RA for that day. A somewhat longer explanation. Assume you had the scope pointed at dec 0 and left it off. Every day any given time - say 21:00 - the RA where it is pointed will have increased by 4 minutes.
What you can do is center the scope to a object with known RA and Dec and set the circles to those values.

[acropolite (Phil)]

No problem with a shadow at noon this far south.