Tuesday, January 22, 2019

imaged POU 1931 (Halifax)

The BGO robot imaged POU 1931 for me. Another neglected double-star, this time in Gemini.

Actually I aimed at GSC 01893 00812 and then used the OFFSET option nudging in RA -10 (west 10%) and Dec -5 (south 5%). This is where the double should be. There's nothing there. The SkyTools chart is similarly void.

It is curious though the tight equal pair of stars east of the equilateral triangle.

neglected double-star POU 1931 in luminance

Luminance only, 2 seconds subexposures, 12 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

The WDS entry is:

06428+2320POU1931      1901 1901    1  38  38   6.0   6.0 10.8  10.8                                            064245.  +231954.

This shows the data is over 100 years old. The PA is 38 and sep 6. Both stars are magnitude 10.8.

That bright pair is at the location in ST3P noted as 6 42 25.7 and +23 19 59. The software calls this Tycho 01893-1748 1. This looks suspiciously like an error in the initially recorded RA data.

That said, ST3P says it is magnitude 12.3. But the stars in the pair look to be the same brightness as the southern stars in the triangle, which the software says are mags 10.6 and 11.5.

I calculate the following:

separation calculated 7.0 arcsec
position angle calculated 41 degrees

Interesting...

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POU 1915 is a faint tight pair to the far north-west.

POU 1944 is the obvious wide pair of faint stars to the north-east.

There's a vertical streak in the centre of the image. Looks like a cosmic ray.

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