Andrew Cooper
Oct 20, 2023    Waikoloa, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 136x
Seeing: 6 Transparency: 7 Moon: 0%

Σ 196 is a delicate 9th and 10th magnitude double found 3' south of HR 577 separated by 22", the brighter SAO 75075 is the northwestern star while SAO 75076 is to the southeast

Checking the WDS listings and Gaia EDR3 data clears up this set of stars... The 9th magnitude star observed above is SAO 75075 listed as AB in WDS, a close binary consisting of a 9.3/10.9 pair separated by 1.8" with matching parallax and proper motion, it is also the closest of the set with about 15mas parallax.

The 10th magnitude star seen 22" south of AB is SAO 75076 or C in WDS, despite the temptation to call it a member based on visual appearance this is actually a background star with a parallax of 2 mas. Oddly the 6th magnitude HR 577 3' north is listed as D of this set by WDS, it is further away than the 9th and 10th magnitude members with a parallax of 9.4mas!

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