astro/basic/moon_bright_limb.go
starainrt 3ffdbe0034
feat: 扩展天文计算能力
- 新增日食、月食、本地可见性、中心线、半影区域、SVG 图示与沙罗周期信息
- 新增行星冲合、留、方照、物理星历、视直径、相位、亮肢角、轨道节点等计算
- 新增木星伽利略卫星位置、现象与接触事件计算
- 新增恒星星表、星座判定、自行修正与观测辅助能力
- 新增 coord、formula、orbit、sundial、lite/sun、lite/moon 等扩展包
- 完善农历年号、月相英文别名、视差角、大气质量、折射、日晷与双星计算
- 增加 NASA、JPL Horizons、IMCCE 等回归测试数据与基线测试
- 重构基础算法文件组织,补充大量公开 API 注释和语义回归测试
- 更新中文和英文 README,补充示例、精度说明、SVG 配图
2026-05-01 22:38:44 +08:00

46 lines
2.3 KiB
Go

package basic
import . "b612.me/astro/tools"
// MoonBrightLimbPositionAngle 月亮明亮边缘位置角 / position angle of the Moon's bright limb.
func MoonBrightLimbPositionAngle(jd float64) float64 {
return MoonBrightLimbPositionAngleN(jd, -1)
}
// MoonBrightLimbPositionAngleN 月亮明亮边缘位置角(截断版) / truncated position angle of the Moon's bright limb.
func MoonBrightLimbPositionAngleN(jd float64, n int) float64 {
sunRA, sunDec := HSunApparentRaDecN(jd, n)
moonRA, moonDec := HMoonTrueRaDecN(jd, n)
return brightLimbPositionAngleFromRaDec(sunRA, sunDec, moonRA, moonDec)
}
// MoonTopocentricBrightLimbPositionAngle 月亮站心明亮边缘位置角 / topocentric position angle of the Moon's bright limb.
func MoonTopocentricBrightLimbPositionAngle(jd, observerLon, observerLat, height float64) float64 {
return MoonTopocentricBrightLimbPositionAngleN(jd, observerLon, observerLat, height, -1)
}
// MoonTopocentricBrightLimbPositionAngleN 月亮站心明亮边缘位置角(截断版) / truncated topocentric position angle of the Moon's bright limb.
func MoonTopocentricBrightLimbPositionAngleN(jd, observerLon, observerLat, height float64, n int) float64 {
sunRA, sunDec := sunTopocentricApparentRaDecN(jd, observerLon, observerLat, height, n)
moonRA, moonDec := moonTopocentricApparentRaDecN(jd, observerLon, observerLat, height, n)
return brightLimbPositionAngleFromRaDec(sunRA, sunDec, moonRA, moonDec)
}
func moonTopocentricApparentRaDecN(jd, observerLon, observerLat, height float64, n int) (float64, float64) {
geocentricRA := HMoonTrueRaN(jd, n)
geocentricDec := HMoonTrueDecN(jd, n)
distanceAU := HMoonAwayN(jd, n) / moonPhysicalAstronomicalUnitKM
return TopocentricRaDec(geocentricRA, geocentricDec, observerLat, observerLon, TD2UT(jd, false), distanceAU, height)
}
func sunTopocentricApparentRaDecN(jd, observerLon, observerLat, height float64, n int) (float64, float64) {
geocentricRA, geocentricDec := HSunApparentRaDecN(jd, n)
return TopocentricRaDec(geocentricRA, geocentricDec, observerLat, observerLon, TD2UT(jd, false), EarthAwayN(jd, n), height)
}
func brightLimbPositionAngleFromRaDec(sunRA, sunDec, bodyRA, bodyDec float64) float64 {
y := Cos(sunDec) * Sin(sunRA-bodyRA)
x := Sin(sunDec)*Cos(bodyDec) - Cos(sunDec)*Sin(bodyDec)*Cos(sunRA-bodyRA)
return ArcTan2(y, x)
}