Thursday, January 28, 2016

found weird entries

When I was aggregating the names of stars, I accessed the GoToStar spreadsheet I had built back in May 2013. And found the named star list was incomplete. Some of the missing entries were obvious, like the Bayer name for Altair. But other things were not so obvious.

This required setting up the mount and powering up the hand controller. I ran through a simulated evening for home. Then I configured for Australia. Then I moved 6 months into the future, still in Australia.

I was able to access every star in the hand controller, including the mysterious item # 44, which I had not been able to extract before.

Then for every entry, I checked the RA and Dec coordinates displayed on the hand controller against the apparent RA and Dec in SkyTools.

GoToStar hand controller display showing star name and location

Glad I finally completed this! For it revealed two extreme errors in the little database.
  • Item 7: Named star: Al Na'ir. The name suggests alpha Gruis. But the coordinates weren't anywhere near there. The closest star was HD 167599 in Sagittarius!
  • Item 166: Named star: Sheratan. Suggests beta Arietis. Nope! The coordinates are near V761 in Cassiopeia.
Minor issues:
  • Found Aspidiske referred to iota Carina, aka Turais.
  • Found a difference in Atik's coordinates. Wondered if they meant zeta and not omicron Persei.
  • Found that Deneb Kaitos referred to beta Cetus, aka Diphda.
  • Found it very odd the database entry for Groombridge 1830, aka HD 103095 in Ursa Major, which ST3P shows as CF UMa. It should be ignored.
  • Found Menkar referred to alpha Cetus, not lambda.
  • Ancha is listed twice, as entry 43 and 47.
Previous testing showed that these weird stars did not appear in the short list of alignment stars. Using 7 and 166 would be dangerous. Maybe that's too strong a word. They would be bad choices to select as the 'scope would go somewhere unusual and if one were to relocate and use the true named star as correct it would surely cause the alignment computations to fail.

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