astro/basic/planet_apparent.go
starainrt 34ff6a36ae
fix: 修正行星事件边界与留点计算
- 统一 UT 事件时刻与 TT 查询时刻的边界判断
- 将外行星留点搜索锚定到对应冲日周期
- 修正水星、金星合日、留、大距事件选择
- 统一七大行星视位置计算辅助逻辑
- 增加公开 Last/Next 边界和 JPL/NAOJ 基线回归测试
2026-05-22 12:24:41 +08:00

85 lines
2.9 KiB
Go

package basic
import (
"math"
"b612.me/astro/planet"
. "b612.me/astro/tools"
)
type planetGeocentricPosition struct {
x float64
y float64
z float64
lo float64
bo float64
}
func planetHeliocentricXYZN(planetIndex int, jd float64, n int) (float64, float64, float64) {
l := planet.WherePlanetN(planetIndex, 0, jd, n)
b := planet.WherePlanetN(planetIndex, 1, jd, n)
r := planet.WherePlanetN(planetIndex, 2, jd, n)
return sphericalToRectangular(l, b, r)
}
func earthHeliocentricXYZN(jd float64, n int) (float64, float64, float64) {
l := planet.WherePlanetN(-1, 0, jd, n)
b := planet.WherePlanetN(-1, 1, jd, n)
r := planet.WherePlanetN(-1, 2, jd, n)
return sphericalToRectangular(l, b, r)
}
func sphericalToRectangular(lo, bo, radius float64) (float64, float64, float64) {
cosBo := math.Cos(bo * math.Pi / 180)
return radius * cosBo * math.Cos(lo*math.Pi/180),
radius * cosBo * math.Sin(lo*math.Pi/180),
radius * math.Sin(bo*math.Pi/180)
}
func geocentricPositionFromRectangular(x, y, z float64) planetGeocentricPosition {
lo := math.Atan2(y, x) * 180 / math.Pi
bo := math.Atan2(z, math.Sqrt(x*x+y*y)) * 180 / math.Pi
return planetGeocentricPosition{
x: x,
y: y,
z: z,
lo: Limit360(lo),
bo: bo,
}
}
func planetGeocentricPositionN(planetIndex int, planetJD, earthJD float64, n int) planetGeocentricPosition {
px, py, pz := planetHeliocentricXYZN(planetIndex, planetJD, n)
ex, ey, ez := earthHeliocentricXYZN(earthJD, n)
return geocentricPositionFromRectangular(px-ex, py-ey, pz-ez)
}
func planetGeocentricPositionWithEarthN(planetIndex int, planetJD float64, ex, ey, ez float64, n int) planetGeocentricPosition {
px, py, pz := planetHeliocentricXYZN(planetIndex, planetJD, n)
return geocentricPositionFromRectangular(px-ex, py-ey, pz-ez)
}
func planetApparentGeocentricPositionN(planetIndex int, jd float64, n int) (planetGeocentricPosition, float64) {
ex, ey, ez := earthHeliocentricXYZN(jd, n)
geoNow := planetGeocentricPositionWithEarthN(planetIndex, jd, ex, ey, ez, n)
tau := 0.0057755183 * math.Sqrt(geoNow.x*geoNow.x+geoNow.y*geoNow.y+geoNow.z*geoNow.z)
geo := planetGeocentricPositionWithEarthN(planetIndex, jd-tau, ex, ey, ez, n)
baseLo := geo.lo
baseBo := geo.bo
geo.lo = Limit360(baseLo + GXCLo(baseLo, baseBo, jd)/3600.0 + Nutation2000Bi(jd))
geo.bo = baseBo + GXCBo(baseLo, baseBo, jd)/3600.0
return geo, tau
}
func planetTrueGeocentricPositionN(planetIndex int, jd float64, n int) (planetGeocentricPosition, float64) {
ex, ey, ez := earthHeliocentricXYZN(jd, n)
geoNow := planetGeocentricPositionWithEarthN(planetIndex, jd, ex, ey, ez, n)
tau := 0.0057755183 * math.Sqrt(geoNow.x*geoNow.x+geoNow.y*geoNow.y+geoNow.z*geoNow.z)
return planetGeocentricPositionWithEarthN(planetIndex, jd-tau, ex, ey, ez, n), tau
}
func planetEarthAwayExplicitN(planetIndex int, jd float64, n int) float64 {
geoNow := planetGeocentricPositionN(planetIndex, jd, jd, n)
return math.Sqrt(geoNow.x*geoNow.x + geoNow.y*geoNow.y + geoNow.z*geoNow.z)
}