Post by Dragon Man on Oct 20, 2015 12:32:47 GMT
Northern Hemispherians have long known about using the star 'Polaris' as the pole star to align an EQ mount in the Northern Hemisphere.
Unfortunately most Southern Hemispherians struggle to polar align by trying to use a star called Polaris Australis (which isn't really the stars name. It is actually 'Sigma Octantis').
It is the closest 'bright' star to the SCP.
Southerners can align the stars of the Octans Trapezium into their respective little black circles IF the Octans Trapezium is printed on their Polar Scope lens! Often it's not.
But for those lucky to have dark sky, there is a Giant Red star called BQ Octantis or HIP 71348 that is practically right on the SCP.
It is so close to the SCP that after polar aligning on it then doing a drift alignment test there is no noticeable star movement in an illuminated reticle even after 15 minutes
Fortunately BQ Octantis is just bright enough to be seen in a Polar Scope if you are setting up in dark skies.
It can easily be seen in little 10x32 Binoculars and finderscopes, but will take fully dark adapted eyes to find in a Polar Scope, but it's there
Fitting a 'Live View' camera will show it easily.
If you don't have the Octans Trapezium printed on your Finderscope, then this star will get you perfectly Polar Aligned. I use it even though I do have the Octans Trapezium in my Polar Scope.
Here is BQ Octantis on a Star map:
Here is a Photograph of the real area:
The green lines mark the SCP
This animation shows where to place the star in the FOV of the Polar Scope. If you place the red star BQ Octantis dead centre in the FOV you can see how close it is to the actual SCP. You can slightly move the star off centre to place the SCP dead centre:
This animation shows the location of BQ Octantis is Stellarium for those that choose to use Stellarium:
This Polar Scope illustration shows how much closer BQ Octantis is to the SCP Pole than Polaris is to the NCP:
About BQ Octantis:
BQ Octantis Variable Giant Red Star in Octans
HIP 71348
Mag 6.8
Spectral Type - M4III
I hope this helps some Southern Hemispherians
Unfortunately most Southern Hemispherians struggle to polar align by trying to use a star called Polaris Australis (which isn't really the stars name. It is actually 'Sigma Octantis').
It is the closest 'bright' star to the SCP.
Southerners can align the stars of the Octans Trapezium into their respective little black circles IF the Octans Trapezium is printed on their Polar Scope lens! Often it's not.
But for those lucky to have dark sky, there is a Giant Red star called BQ Octantis or HIP 71348 that is practically right on the SCP.
It is so close to the SCP that after polar aligning on it then doing a drift alignment test there is no noticeable star movement in an illuminated reticle even after 15 minutes
Fortunately BQ Octantis is just bright enough to be seen in a Polar Scope if you are setting up in dark skies.
It can easily be seen in little 10x32 Binoculars and finderscopes, but will take fully dark adapted eyes to find in a Polar Scope, but it's there
Fitting a 'Live View' camera will show it easily.
If you don't have the Octans Trapezium printed on your Finderscope, then this star will get you perfectly Polar Aligned. I use it even though I do have the Octans Trapezium in my Polar Scope.
Here is BQ Octantis on a Star map:
Here is a Photograph of the real area:
The green lines mark the SCP
This animation shows where to place the star in the FOV of the Polar Scope. If you place the red star BQ Octantis dead centre in the FOV you can see how close it is to the actual SCP. You can slightly move the star off centre to place the SCP dead centre:
This animation shows the location of BQ Octantis is Stellarium for those that choose to use Stellarium:
This Polar Scope illustration shows how much closer BQ Octantis is to the SCP Pole than Polaris is to the NCP:
About BQ Octantis:
BQ Octantis Variable Giant Red Star in Octans
HIP 71348
Mag 6.8
Spectral Type - M4III
I hope this helps some Southern Hemispherians