616 lines
15 KiB
Go
616 lines
15 KiB
Go
package basic
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import (
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"math"
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"b612.me/astro/planet"
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. "b612.me/astro/tools"
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)
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func VenusL(JD float64) float64 {
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return planet.WherePlanet(2, 0, JD)
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}
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func VenusB(JD float64) float64 {
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return planet.WherePlanet(2, 1, JD)
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}
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func VenusR(JD float64) float64 {
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return planet.WherePlanet(2, 2, JD)
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}
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func AVenusX(JD float64) float64 {
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l := VenusL(JD)
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b := VenusB(JD)
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r := VenusR(JD)
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el := planet.WherePlanet(-1, 0, JD)
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eb := planet.WherePlanet(-1, 1, JD)
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er := planet.WherePlanet(-1, 2, JD)
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x := r*Cos(b)*Cos(l) - er*Cos(eb)*Cos(el)
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return x
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}
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func AVenusY(JD float64) float64 {
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l := VenusL(JD)
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b := VenusB(JD)
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r := VenusR(JD)
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el := planet.WherePlanet(-1, 0, JD)
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eb := planet.WherePlanet(-1, 1, JD)
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er := planet.WherePlanet(-1, 2, JD)
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y := r*Cos(b)*Sin(l) - er*Cos(eb)*Sin(el)
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return y
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}
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func AVenusZ(JD float64) float64 {
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//l := VenusL(JD)
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b := VenusB(JD)
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r := VenusR(JD)
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// el := planet.WherePlanet(-1, 0, JD)
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eb := planet.WherePlanet(-1, 1, JD)
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er := planet.WherePlanet(-1, 2, JD)
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z := r*Sin(b) - er*Sin(eb)
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return z
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}
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func AVenusXYZ(JD float64) (float64, float64, float64) {
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l := VenusL(JD)
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b := VenusB(JD)
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r := VenusR(JD)
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el := planet.WherePlanet(-1, 0, JD)
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eb := planet.WherePlanet(-1, 1, JD)
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er := planet.WherePlanet(-1, 2, JD)
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x := r*Cos(b)*Cos(l) - er*Cos(eb)*Cos(el)
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y := r*Cos(b)*Sin(l) - er*Cos(eb)*Sin(el)
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z := r*Sin(b) - er*Sin(eb)
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return x, y, z
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}
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func VenusApparentRa(JD float64) float64 {
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lo, bo := VenusApparentLoBo(JD)
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sita := Sita(JD)
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ra := math.Atan2((Sin(lo)*Cos(sita) - Tan(bo)*Sin(sita)), Cos(lo))
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ra = ra * 180 / math.Pi
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return Limit360(ra)
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}
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func VenusApparentDec(JD float64) float64 {
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lo, bo := VenusApparentLoBo(JD)
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sita := Sita(JD)
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dec := ArcSin(Sin(bo)*Cos(sita) + Cos(bo)*Sin(sita)*Sin(lo))
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return dec
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}
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func VenusApparentRaDec(JD float64) (float64, float64) {
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lo, bo := VenusApparentLoBo(JD)
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sita := Sita(JD)
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ra := math.Atan2((Sin(lo)*Cos(sita) - Tan(bo)*Sin(sita)), Cos(lo))
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ra = ra * 180 / math.Pi
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dec := ArcSin(Sin(bo)*Cos(sita) + Cos(bo)*Sin(sita)*Sin(lo))
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return Limit360(ra), dec
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}
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func EarthVenusAway(JD float64) float64 {
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x, y, z := AVenusXYZ(JD)
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to := math.Sqrt(x*x + y*y + z*z)
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return to
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}
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func VenusApparentLo(JD float64) float64 {
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x, y, z := AVenusXYZ(JD)
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to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z)
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x, y, z = AVenusXYZ(JD - to)
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lo := math.Atan2(y, x)
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bo := math.Atan2(z, math.Sqrt(x*x+y*y))
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lo = lo * 180 / math.Pi
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bo = bo * 180 / math.Pi
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lo = Limit360(lo)
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//lo-=GXCLo(lo,bo,JD)/3600;
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//bo+=GXCBo(lo,bo,JD);
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lo += Nutation2000Bi(JD)
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return lo
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}
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func VenusApparentBo(JD float64) float64 {
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x, y, z := AVenusXYZ(JD)
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to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z)
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x, y, z = AVenusXYZ(JD - to)
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//lo := math.Atan2(y, x)
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bo := math.Atan2(z, math.Sqrt(x*x+y*y))
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//lo = lo * 180 / math.Pi
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bo = bo * 180 / math.Pi
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//lo+=GXCLo(lo,bo,JD);
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//bo+=GXCBo(lo,bo,JD)/3600;
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//lo+=Nutation2000Bi(JD);
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return bo
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}
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func VenusApparentLoBo(JD float64) (float64, float64) {
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x, y, z := AVenusXYZ(JD)
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to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z)
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x, y, z = AVenusXYZ(JD - to)
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lo := math.Atan2(y, x)
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bo := math.Atan2(z, math.Sqrt(x*x+y*y))
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lo = lo * 180 / math.Pi
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bo = bo * 180 / math.Pi
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lo = Limit360(lo)
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//lo-=GXCLo(lo,bo,JD)/3600;
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//bo+=GXCBo(lo,bo,JD);
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lo += Nutation2000Bi(JD)
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return lo, bo
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}
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func VenusMag(JD float64) float64 {
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AwaySun := VenusR(JD)
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AwayEarth := EarthVenusAway(JD)
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Away := planet.WherePlanet(-1, 2, JD)
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i := (AwaySun*AwaySun + AwayEarth*AwayEarth - Away*Away) / (2 * AwaySun * AwayEarth)
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i = ArcCos(i)
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Mag := -4.40 + 5*math.Log10(AwaySun*AwayEarth) + 0.0009*i + 0.000239*i*i - 0.00000065*i*i*i
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return FloatRound(Mag, 2)
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}
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func VenusHeight(jde, lon, lat, timezone float64) float64 {
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// 转换为世界时
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utcJde := jde - timezone/24.0
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// 计算视恒星时
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ra, dec := VenusApparentRaDec(TD2UT(utcJde, true))
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st := Limit360(ApparentSiderealTime(utcJde)*15 + lon)
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// 计算时角
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H := Limit360(st - ra)
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// 高度角、时角与天球座标三角转换公式
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// sin(h)=sin(lat)*sin(dec)+cos(dec)*cos(lat)*cos(H)
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sinHeight := Sin(lat)*Sin(dec) + Cos(dec)*Cos(lat)*Cos(H)
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return ArcSin(sinHeight)
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}
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func VenusAzimuth(jde, lon, lat, timezone float64) float64 {
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// 转换为世界时
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utcJde := jde - timezone/24.0
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// 计算视恒星时
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ra, dec := VenusApparentRaDec(TD2UT(utcJde, true))
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st := Limit360(ApparentSiderealTime(utcJde)*15 + lon)
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// 计算时角
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H := Limit360(st - ra)
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// 三角转换公式
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tanAzimuth := Sin(H) / (Cos(H)*Sin(lat) - Tan(dec)*Cos(lat))
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Azimuth := ArcTan(tanAzimuth)
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if Azimuth < 0 {
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if H/15 < 12 {
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return Azimuth + 360
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}
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return Azimuth + 180
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}
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if H/15 < 12 {
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return Azimuth + 180
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}
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return Azimuth
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}
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func VenusHourAngle(JD, Lon, TZ float64) float64 {
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startime := Limit360(ApparentSiderealTime(JD-TZ/24)*15 + Lon)
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timeangle := startime - VenusApparentRa(TD2UT(JD-TZ/24.0, true))
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if timeangle < 0 {
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timeangle += 360
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}
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return timeangle
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}
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func VenusCulminationTime(jde, lon, timezone float64) float64 {
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//jde 世界时，非力学时，当地时区 0时，无需转换力学时
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//ra,dec 瞬时天球座标，非J2000等时间天球坐标
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jde = math.Floor(jde) + 0.5
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JD1 := jde + Limit360(360-VenusHourAngle(jde, lon, timezone))/15.0/24.0*0.99726851851851851851
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limitHA := func(jde, lon, timezone float64) float64 {
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ha := VenusHourAngle(jde, lon, timezone)
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if ha < 180 {
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ha += 360
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}
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return ha
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}
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for {
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JD0 := JD1
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stDegree := limitHA(JD0, lon, timezone) - 360
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stDegreep := (limitHA(JD0+0.000005, lon, timezone) - limitHA(JD0-0.000005, lon, timezone)) / 0.00001
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JD1 = JD0 - stDegree/stDegreep
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if math.Abs(JD1-JD0) <= 0.00001 {
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break
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}
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}
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return JD1
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}
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func VenusRiseTime(JD, Lon, Lat, TZ, ZS, HEI float64) float64 {
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return venusRiseDown(JD, Lon, Lat, TZ, ZS, HEI, true)
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}
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func VenusDownTime(JD, Lon, Lat, TZ, ZS, HEI float64) float64 {
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return venusRiseDown(JD, Lon, Lat, TZ, ZS, HEI, false)
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}
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func venusRiseDown(JD, Lon, Lat, TZ, ZS, HEI float64, isRise bool) float64 {
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var An float64
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JD = math.Floor(JD) + 0.5
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ntz := math.Round(Lon / 15)
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if ZS != 0 {
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An = -0.8333
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}
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An = An - HeightDegreeByLat(HEI, Lat)
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tztime := VenusCulminationTime(JD, Lon, ntz)
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if VenusHeight(tztime, Lon, Lat, ntz) < An {
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return -2 //极夜
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}
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if VenusHeight(tztime-0.5, Lon, Lat, ntz) > An {
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return -1 //极昼
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}
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dec := HSunApparentDec(TD2UT(tztime-ntz/24, true))
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//(sin(ho)-sin(φ)*sin(δ2))/(cos(φ)*cos(δ2))
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tmp := (Sin(An) - Sin(dec)*Sin(Lat)) / (Cos(dec) * Cos(Lat))
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var rise float64
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if math.Abs(tmp) <= 1 {
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rzsc := ArcCos(tmp) / 15
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if isRise {
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rise = tztime - rzsc/24 - 25.0/24.0/60.0
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} else {
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rise = tztime + rzsc/24 - 25.0/24.0/60.0
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}
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} else {
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rise = tztime
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i := 0
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//TODO:使用二分法计算
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for VenusHeight(rise, Lon, Lat, ntz) > An {
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i++
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if isRise {
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rise -= 15.0 / 60.0 / 24.0
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} else {
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rise += 15.0 / 60.0 / 24.0
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}
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if i > 48 {
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break
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}
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}
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}
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JD1 := rise
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for {
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JD0 := JD1
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stDegree := VenusHeight(JD0, Lon, Lat, ntz) - An
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stDegreep := (VenusHeight(JD0+0.000005, Lon, Lat, ntz) - VenusHeight(JD0-0.000005, Lon, Lat, ntz)) / 0.00001
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JD1 = JD0 - stDegree/stDegreep
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if math.Abs(JD1-JD0) <= 0.00001 {
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break
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}
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}
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return JD1 - ntz/24 + TZ/24
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}
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// Pos
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const VENUS_S_PERIOD = 1 / ((1 / 224.701) - (1 / 365.256363004))
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func venusConjunction(jde float64, next uint8) float64 {
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//0=last 1=next
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decSub := func(jde float64) float64 {
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sub := Limit360(VenusApparentLo(jde) - HSunApparentLo(jde))
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if sub > 180 {
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sub -= 360
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}
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if sub < -180 {
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sub += 360
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}
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return sub
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}
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nowSub := decSub(jde)
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pos := math.Abs(decSub(jde+1/86400.0)) - math.Abs(nowSub)
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if pos >= 0 && next == 1 && nowSub > 0 {
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jde += VENUS_S_PERIOD/8.0 + 2
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}
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if pos >= 0 && next == 1 && nowSub < 0 {
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jde += VENUS_S_PERIOD/6.0 + 2
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}
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if pos <= 0 && next == 0 && nowSub < 0 {
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jde -= VENUS_S_PERIOD/8.0 + 2
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}
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if pos <= 0 && next == 0 && nowSub > 0 {
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jde -= VENUS_S_PERIOD/6.0 + 2
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}
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for {
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nowSub := decSub(jde)
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pos := math.Abs(decSub(jde+1/86400.0)) - math.Abs(nowSub)
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if math.Abs(nowSub) > 24 || (pos > 0 && next == 1) || (pos < 0 && next == 0) {
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if next == 1 {
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jde += 8
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} else {
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jde -= 8
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}
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continue
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}
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break
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}
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JD1 := jde
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for {
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JD0 := JD1
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stDegree := decSub(JD0)
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stDegreep := (decSub(JD0+0.000005) - decSub(JD0-0.000005)) / 0.00001
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JD1 = JD0 - stDegree/stDegreep
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if math.Abs(JD1-JD0) <= 0.00001 {
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break
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}
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}
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return TD2UT(JD1, false)
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}
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func LastVenusConjunction(jde float64) float64 {
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return venusConjunction(jde, 0)
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}
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func NextVenusConjunction(jde float64) float64 {
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return venusConjunction(jde, 1)
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}
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func NextVenusInferiorConjunction(jde float64) float64 {
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date := NextVenusConjunction(jde)
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if EarthVenusAway(date) > EarthAway(date) {
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return NextVenusConjunction(date + 2)
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}
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return date
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}
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func NextVenusSuperiorConjunction(jde float64) float64 {
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date := NextVenusConjunction(jde)
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if EarthVenusAway(date) < EarthAway(date) {
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return NextVenusConjunction(date + 2)
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}
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return date
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}
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func LastVenusInferiorConjunction(jde float64) float64 {
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date := LastVenusConjunction(jde)
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if EarthVenusAway(date) > EarthAway(date) {
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return LastVenusConjunction(date - 2)
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}
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return date
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}
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func LastVenusSuperiorConjunction(jde float64) float64 {
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date := LastVenusConjunction(jde)
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if EarthVenusAway(date) < EarthAway(date) {
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return LastVenusConjunction(date - 2)
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}
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return date
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}
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func venusRetrograde(jde float64) float64 {
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//0=last 1=next
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decSunSub := func(jde float64) float64 {
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sub := Limit360(VenusApparentRa(jde) - SunApparentRa(jde))
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if sub > 180 {
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sub -= 360
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}
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if sub < -180 {
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sub += 360
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}
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return sub
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}
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decSub := func(jde float64, val float64) float64 {
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sub := VenusApparentRa(jde+val) - VenusApparentRa(jde-val)
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if sub > 180 {
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sub -= 360
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}
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if sub < -180 {
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sub += 360
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}
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return sub / (2 * val)
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}
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lastHe := LastVenusConjunction(jde)
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nextHe := NextVenusConjunction(jde)
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nowSub := decSunSub(jde)
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if nowSub > 0 {
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jde = lastHe + ((nextHe - lastHe) / 5.0 * 3.5)
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} else {
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jde = lastHe + 10
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}
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for {
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nowSub := decSub(jde, 1.0/86400.0)
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if math.Abs(nowSub) > 0.5 {
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jde += 5
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continue
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}
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break
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}
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JD1 := jde
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for {
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JD0 := JD1
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stDegree := decSub(JD0, 0.5/86400.0)
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stDegreep := (decSub(JD0+10.0/86400.0, 0.5/86400.0) - decSub(JD0-10.0/86400.0, 0.5/86400.0)) / (20.0 / 86400.0)
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JD1 = JD0 - stDegree/stDegreep
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if math.Abs(JD1-JD0) <= 20.0/86400.0 {
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break
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}
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}
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JD1 = JD1 - 10.0/86400.0
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min := JD1
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minRa := 100.0
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for i := 0.0; i < 40.0; i++ {
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tmp := decSub(JD1+i*0.5/86400.0, 0.5/86400.0)
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if math.Abs(tmp) < math.Abs(minRa) {
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minRa = tmp
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min = JD1 + i*0.5/86400.0
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}
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}
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//fmt.Println((min - lastHe) / (nextHe - lastHe))
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return TD2UT(min, false)
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}
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func NextVenusRetrograde(jde float64) float64 {
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date := venusRetrograde(jde)
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if date < jde {
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nextHe := NextVenusConjunction(jde)
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return venusRetrograde(nextHe + 2)
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}
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return date
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}
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func LastVenusRetrograde(jde float64) float64 {
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lastHe := LastVenusConjunction(jde)
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date := venusRetrograde(lastHe + 2)
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if date > jde {
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lastLastHe := LastVenusConjunction(lastHe - 2)
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return venusRetrograde(lastLastHe + 2)
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}
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return date
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}
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func NextVenusProgradeToRetrograde(jde float64) float64 {
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date := NextVenusRetrograde(jde)
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sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
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if sub > 180 {
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return NextVenusRetrograde(date + VENUS_S_PERIOD/2)
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}
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return date
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}
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func NextVenusRetrogradeToPrograde(jde float64) float64 {
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date := NextVenusRetrograde(jde)
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sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub < 180 {
|
||
return NextVenusRetrograde(date + 12)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func LastVenusProgradeToRetrograde(jde float64) float64 {
|
||
date := LastVenusRetrograde(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub > 180 {
|
||
return LastVenusRetrograde(date - 12)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func LastVenusRetrogradeToPrograde(jde float64) float64 {
|
||
date := LastVenusRetrograde(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub < 180 {
|
||
return LastVenusRetrograde(date - VENUS_S_PERIOD/2)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func VenusSunElongation(jde float64) float64 {
|
||
lo1, bo1 := VenusApparentLoBo(jde)
|
||
lo2 := SunApparentLo(jde)
|
||
bo2 := HSunTrueBo(jde)
|
||
return StarAngularSeparation(lo1, bo1, lo2, bo2)
|
||
}
|
||
func venusGreatestElongation(jde float64) float64 {
|
||
decSunSub := func(jde float64) float64 {
|
||
sub := Limit360(VenusApparentRa(jde) - SunApparentRa(jde))
|
||
if sub > 180 {
|
||
sub -= 360
|
||
}
|
||
if sub < -180 {
|
||
sub += 360
|
||
}
|
||
return sub
|
||
}
|
||
decSub := func(jde float64, val float64) float64 {
|
||
sub := VenusSunElongation(jde+val) - VenusSunElongation(jde-val)
|
||
if sub > 180 {
|
||
sub -= 360
|
||
}
|
||
if sub < -180 {
|
||
sub += 360
|
||
}
|
||
return sub / (2 * val)
|
||
}
|
||
lastHe := LastVenusConjunction(jde)
|
||
nextHe := NextVenusConjunction(jde)
|
||
nowSub := decSunSub(jde)
|
||
if nowSub > 0 {
|
||
jde = lastHe + ((nextHe - lastHe) / 5.0 * 2.5)
|
||
} else {
|
||
jde = lastHe + ((nextHe - lastHe) / 5.0)
|
||
}
|
||
for {
|
||
nowSub := decSub(jde, 1.0/86400.0)
|
||
if math.Abs(nowSub) > 0.15 {
|
||
jde += 5
|
||
continue
|
||
}
|
||
break
|
||
}
|
||
JD1 := jde
|
||
for {
|
||
JD0 := JD1
|
||
stDegree := decSub(JD0, 2.0/86400.0)
|
||
stDegreep := (decSub(JD0+15.0/86400.0, 2.0/86400.0) - decSub(JD0-15.0/86400.0, 2.0/86400.0)) / (30.0 / 86400.0)
|
||
JD1 = JD0 - stDegree/stDegreep
|
||
if math.Abs(JD1-JD0) <= 30.0/86400.0 {
|
||
break
|
||
}
|
||
}
|
||
JD1 = JD1 - 15.0/86400.0
|
||
min := JD1
|
||
minRa := 100.0
|
||
for i := 0.0; i < 60.0; i++ {
|
||
tmp := decSub(JD1+i*0.5/86400.0, 0.5/86400.0)
|
||
if math.Abs(tmp) < math.Abs(minRa) {
|
||
minRa = tmp
|
||
min = JD1 + i*0.5/86400.0
|
||
}
|
||
}
|
||
//fmt.Println((min - lastHe) / (nextHe - lastHe))
|
||
return TD2UT(min, false)
|
||
}
|
||
|
||
func NextVenusGreatestElongation(jde float64) float64 {
|
||
date := venusGreatestElongation(jde)
|
||
if date < jde {
|
||
nextHe := NextVenusConjunction(jde)
|
||
return venusGreatestElongation(nextHe + 2)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func LastVenusGreatestElongation(jde float64) float64 {
|
||
lastHe := LastVenusConjunction(jde)
|
||
date := venusGreatestElongation(lastHe + 2)
|
||
if date > jde {
|
||
lastLastHe := LastVenusConjunction(lastHe - 2)
|
||
return venusGreatestElongation(lastLastHe + 2)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func NextVenusGreatestElongationEast(jde float64) float64 {
|
||
date := NextVenusGreatestElongation(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub > 180 {
|
||
return NextVenusGreatestElongation(date + 1)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func NextVenusGreatestElongationWest(jde float64) float64 {
|
||
date := NextVenusGreatestElongation(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub < 180 {
|
||
return NextVenusGreatestElongation(date + 1)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func LastVenusGreatestElongationEast(jde float64) float64 {
|
||
date := LastVenusGreatestElongation(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub > 180 {
|
||
return LastVenusGreatestElongation(date - 1)
|
||
}
|
||
return date
|
||
}
|
||
|
||
func LastVenusGreatestElongationWest(jde float64) float64 {
|
||
date := LastVenusGreatestElongation(jde)
|
||
sub := Limit360(VenusApparentRa(date) - SunApparentRa(date))
|
||
if sub < 180 {
|
||
return LastVenusGreatestElongation(date - 1)
|
||
}
|
||
return date
|
||
}
|