feat: 完善时标与天象几何计算并扩展输出接口

- 新增时标、ΔT 模型、质心时间与 UT1 支持
- 改进日月食、月掩、行星事件及路径边界计算
- 完善恒星三维自行与动态距离传播
- 扩展 SVG、GeoJSON、KML 输出与底层距离换算工具
- 整理中英文手册、示例资源及回归测试

planet/sun_low.go

@@ -3,51 +3,51 @@ package planet
 import . "b612.me/astro/tools"
 
 // SunLo 太阳几何黄经
-func SunLo(jd float64) float64 {
-	T := (jd - 2451545) / 365250
+func SunLo(jde float64) float64 {
+	T := (jde - 2451545) / 365250
 	SunLo := 280.4664567 + 360007.6982779*T + 0.03032028*T*T + T*T*T/49931 - T*T*T*T/15299 - T*T*T*T*T/1988000
 	return Limit360(SunLo)
 }
 
-func SunM(JD float64) float64 {
-	T := (JD - 2451545) / 36525
+func SunM(JDE float64) float64 {
+	T := (JDE - 2451545) / 36525
 	sunM := 357.5291092 + 35999.0502909*T - 0.0001559*T*T - 0.00000048*T*T*T
 	return Limit360(sunM)
 }
 
 // Earthe 地球偏心率
-func Earthe(JD float64) float64 {
-	T := (JD - 2451545) / 36525
+func Earthe(JDE float64) float64 {
+	T := (JDE - 2451545) / 36525
 	Earthe := 0.016708617 - 0.000042037*T - 0.0000001236*T*T
 	return Earthe
 }
 
-func EarthPI(JD float64) float64 {
-	T := (JD - 2451545) / 36525
+func EarthPI(JDE float64) float64 {
+	T := (JDE - 2451545) / 36525
 	return 102.93735 + 1.71953*T + 0.00046*T*T
 }
 
-func SunMidFun(JD float64) float64 {
-	T := (JD - 2451545) / 36525
-	M := SunM(JD)
+func SunMidFun(JDE float64) float64 {
+	T := (JDE - 2451545) / 36525
+	M := SunM(JDE)
 	SunMidFun := (1.9146-0.004817*T-0.000014*T*T)*Sin(M) + (0.019993-0.000101*T)*Sin(2*M) + 0.00029*Sin(3*M)
 	return SunMidFun
 }
 
-func SunTrueLo(JD float64) float64 {
-	SunTrueLo := SunLo(JD) + SunMidFun(JD)
+func SunTrueLo(JDE float64) float64 {
+	SunTrueLo := SunLo(JDE) + SunMidFun(JDE)
 	return SunTrueLo
 }
 
-func SunApparentLo(JD float64) float64 {
-	T := (JD - 2451545) / 36525
-	SunApparentLo := SunTrueLo(JD) - 0.00569 - 0.00478*Sin(125.04-1934.136*T)
+func SunApparentLo(JDE float64) float64 {
+	T := (JDE - 2451545) / 36525
+	SunApparentLo := SunTrueLo(JDE) - 0.00569 - 0.00478*Sin(125.04-1934.136*T)
 	return SunApparentLo
 }
 
-func Distance(jd float64) float64 {
-	f := SunMidFun(jd)
-	m := SunM(jd)
-	e := Earthe(jd)
+func Distance(jde float64) float64 {
+	f := SunMidFun(jde)
+	m := SunM(jde)
+	e := Earthe(jde)
 	return 1.000001018 * (1 - e*e) / (1 + e*Cos(f+m))
 }