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Re: Skyfield
From: Lars Bergman
Date: 2018 Oct 23, 03:31 -0700
From: Lars Bergman
Date: 2018 Oct 23, 03:31 -0700
Robin wrote
"I’ll leave it to you to decide whether the NA of the time quotes more significant figures than are justified."
I think the number of significant figures are justified, but there seems to be a systematic error somewhere. Skyfield RA values are 0.93 to 0.95 seconds of time larger than the NA values. Skyfield declination values are also larger than the NA values, ranging from 2.3 to 0.8 seconds of arc during this day, seemingly quite linearly. See enclosed Excel file.
Lars, 59°N 18°E
