24 lines
953 B
Go
24 lines
953 B
Go
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package coord
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import (
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"time"
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"b612.me/astro/basic"
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)
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// ParallacticAngleByHourAngle 由时角计算视差角（天顶方向角） / parallactic angle from hour angle.
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//
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// hourAngle/dec/observerLat 单位均为度，返回值通常落在 [-180, 180] 度。
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func ParallacticAngleByHourAngle(hourAngle, dec, observerLat float64) float64 {
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return basic.ParallacticAngleByHourAngle(hourAngle, dec, observerLat)
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}
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// ParallacticAngle 由赤经赤纬计算视差角（天顶方向角） / parallactic angle from right ascension and declination.
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//
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// ra/dec 为瞬时赤经赤纬；observerLon/observerLat 为观测者经纬度，东正西负、北正南负。
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// Returns the signed parallactic angle for the apparent equatorial coordinates
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// at the observing instant.
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func ParallacticAngle(date time.Time, ra, dec, observerLon, observerLat float64) float64 {
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return basic.StarParallacticAngle(jdeUTC(date), ra, dec, observerLon, observerLat, 0)
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}
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