Tuesday, March 19, 2019

imaged HJ 465 (Halifax)

Captured the double star HJ 465 in Leo with the BGO system. Aimed at GSC 01959 00225 which then puts the faint double in question in the lower portion of the image.

double-star HJ 465 in luminance

Luminance only, 1 second sub, 12 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

This double star target was chosen from an old "neglected" list at the WDS. I initially used the location, 09312+2446, in the ID to try to find the object. There was nothing at the location in SkyTools 3 Pro. But ST3P showed a conspicuous pair due south at +24 36! Proper motion? Looked like an entry error in the coordinates to me. Also my software showed the pair data was dated 1915. Over 100 years old. I selected the star GSC 01959-0225, kind of in the middle, for the Burke-Gaffney robot.

The image clearly shows the pair with the brighter element to the west. They are nearly in a perfect east-west orientation. There's a neat big funnel shape...

I plate-solved the (rotated) FITS image with astrometry.net. The image centre is at 09h 31m 11.498s and +24° 41' 53.307". The image size 23.9 x 23.9 arcmin with a radius of 0.282 deg. The pixel scale is 0.934 arcsec/pixel. The image is rotated from the equatorial coordinate system very slightly: up is 0.298 degrees E of N.

As I examine the current "main" Washington Double Star 06-11 list now, I see there have been 9 observations for HJ 465 with the most recent in 2015. I don't see any notes on the database entry. Most importantly, the WDS shows the precise coordinates as 093112.74+243605.5 so all appears good now...

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