package basic import ( "math" "b612.me/astro/planet" . "b612.me/astro/tools" ) func VenusL(jd float64) float64 { return planet.WherePlanet(2, 0, jd) } func VenusB(jd float64) float64 { return planet.WherePlanet(2, 1, jd) } func VenusR(jd float64) float64 { return planet.WherePlanet(2, 2, jd) } func AVenusX(jd float64) float64 { l := VenusL(jd) b := VenusB(jd) r := VenusR(jd) el := planet.WherePlanet(-1, 0, jd) eb := planet.WherePlanet(-1, 1, jd) er := planet.WherePlanet(-1, 2, jd) x := r*Cos(b)*Cos(l) - er*Cos(eb)*Cos(el) return x } func AVenusY(jd float64) float64 { l := VenusL(jd) b := VenusB(jd) r := VenusR(jd) el := planet.WherePlanet(-1, 0, jd) eb := planet.WherePlanet(-1, 1, jd) er := planet.WherePlanet(-1, 2, jd) y := r*Cos(b)*Sin(l) - er*Cos(eb)*Sin(el) return y } func AVenusZ(jd float64) float64 { //l := VenusL(jd) b := VenusB(jd) r := VenusR(jd) // el := planet.WherePlanet(-1, 0, jd) eb := planet.WherePlanet(-1, 1, jd) er := planet.WherePlanet(-1, 2, jd) z := r*Sin(b) - er*Sin(eb) return z } func AVenusXYZ(jd float64) (float64, float64, float64) { l := VenusL(jd) b := VenusB(jd) r := VenusR(jd) el := planet.WherePlanet(-1, 0, jd) eb := planet.WherePlanet(-1, 1, jd) er := planet.WherePlanet(-1, 2, jd) x := r*Cos(b)*Cos(l) - er*Cos(eb)*Cos(el) y := r*Cos(b)*Sin(l) - er*Cos(eb)*Sin(el) z := r*Sin(b) - er*Sin(eb) return x, y, z } func VenusApparentRa(jd float64) float64 { lo, bo := VenusApparentLoBo(jd) eps := TrueObliquity(jd) ra := math.Atan2((Sin(lo)*Cos(eps) - Tan(bo)*Sin(eps)), Cos(lo)) ra = ra * 180 / math.Pi return Limit360(ra) } func VenusApparentDec(jd float64) float64 { lo, bo := VenusApparentLoBo(jd) eps := TrueObliquity(jd) dec := ArcSin(Sin(bo)*Cos(eps) + Cos(bo)*Sin(eps)*Sin(lo)) return dec } func VenusApparentRaDec(jd float64) (float64, float64) { lo, bo := VenusApparentLoBo(jd) eps := TrueObliquity(jd) ra := math.Atan2((Sin(lo)*Cos(eps) - Tan(bo)*Sin(eps)), Cos(lo)) ra = ra * 180 / math.Pi dec := ArcSin(Sin(bo)*Cos(eps) + Cos(bo)*Sin(eps)*Sin(lo)) return Limit360(ra), dec } func EarthVenusAway(jd float64) float64 { x, y, z := AVenusXYZ(jd) to := math.Sqrt(x*x + y*y + z*z) return to } func VenusApparentLo(jd float64) float64 { x, y, z := AVenusXYZ(jd) to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z) x, y, z = AVenusXYZ(jd - to) lo := math.Atan2(y, x) bo := math.Atan2(z, math.Sqrt(x*x+y*y)) lo = lo * 180 / math.Pi bo = bo * 180 / math.Pi lo = Limit360(lo) //lo-=GXCLo(lo,bo,jd)/3600; //bo+=GXCBo(lo,bo,jd); lo += Nutation2000Bi(jd) return lo } func VenusApparentBo(jd float64) float64 { x, y, z := AVenusXYZ(jd) to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z) x, y, z = AVenusXYZ(jd - to) //lo := math.Atan2(y, x) bo := math.Atan2(z, math.Sqrt(x*x+y*y)) //lo = lo * 180 / math.Pi bo = bo * 180 / math.Pi //lo+=GXCLo(lo,bo,jd); //bo+=GXCBo(lo,bo,jd)/3600; //lo+=Nutation2000Bi(jd); return bo } func VenusApparentLoBo(jd float64) (float64, float64) { x, y, z := AVenusXYZ(jd) to := 0.0057755183 * math.Sqrt(x*x+y*y+z*z) x, y, z = AVenusXYZ(jd - to) lo := math.Atan2(y, x) bo := math.Atan2(z, math.Sqrt(x*x+y*y)) lo = lo * 180 / math.Pi bo = bo * 180 / math.Pi lo = Limit360(lo) //lo-=GXCLo(lo,bo,jd)/3600; //bo+=GXCBo(lo,bo,jd); lo += Nutation2000Bi(jd) return lo, bo } func VenusMag(jd float64) float64 { sunDistance := VenusR(jd) earthDistance := EarthVenusAway(jd) earthSunDistance := planet.WherePlanet(-1, 2, jd) i := (sunDistance*sunDistance + earthDistance*earthDistance - earthSunDistance*earthSunDistance) / (2 * sunDistance * earthDistance) i = ArcCos(i) mag := -4.40 + 5*math.Log10(sunDistance*earthDistance) + 0.0009*i + 0.000239*i*i - 0.00000065*i*i*i return FloatRound(mag, 2) } func VenusHeight(jde, lon, lat, timezone float64) float64 { // 转换为世界时 utcJde := jde - timezone/24.0 // 计算视恒星时 ra, dec := VenusApparentRaDec(TD2UT(utcJde, true)) st := Limit360(ApparentSiderealTime(utcJde)*15 + lon) // 计算时角 hourAngle := Limit360(st - ra) // 高度角、时角与天球座标三角转换公式 // sin(h)=sin(lat)*sin(dec)+cos(dec)*cos(lat)*cos(hourAngle) sinHeight := Sin(lat)*Sin(dec) + Cos(dec)*Cos(lat)*Cos(hourAngle) return ArcSin(sinHeight) } func VenusAzimuth(jde, lon, lat, timezone float64) float64 { // 转换为世界时 utcJde := jde - timezone/24.0 // 计算视恒星时 ra, dec := VenusApparentRaDec(TD2UT(utcJde, true)) st := Limit360(ApparentSiderealTime(utcJde)*15 + lon) // 计算时角 hourAngle := Limit360(st - ra) // 三角转换公式 tanAzimuth := Sin(hourAngle) / (Cos(hourAngle)*Sin(lat) - Tan(dec)*Cos(lat)) azimuth := ArcTan(tanAzimuth) if azimuth < 0 { if hourAngle/15 < 12 { return azimuth + 360 } return azimuth + 180 } if hourAngle/15 < 12 { return azimuth + 180 } return azimuth } func VenusHourAngle(jd, lon, tz float64) float64 { startime := Limit360(ApparentSiderealTime(jd-tz/24)*15 + lon) timeangle := startime - VenusApparentRa(TD2UT(jd-tz/24.0, true)) if timeangle < 0 { timeangle += 360 } return timeangle } func VenusCulminationTime(jde, lon, timezone float64) float64 { //jde 世界时,非力学时,当地时区 0时,无需转换力学时 //ra,dec 瞬时天球座标,非J2000等时间天球坐标 jde = math.Floor(jde) + 0.5 estimateJD := jde + Limit360(360-VenusHourAngle(jde, lon, timezone))/15.0/24.0*0.99726851851851851851 limitHA := func(jde, lon, timezone float64) float64 { ha := VenusHourAngle(jde, lon, timezone) if ha < 180 { ha += 360 } return ha } for { prevJD := estimateJD stDegree := limitHA(prevJD, lon, timezone) - 360 stDegreep := (limitHA(prevJD+0.000005, lon, timezone) - limitHA(prevJD-0.000005, lon, timezone)) / 0.00001 estimateJD = prevJD - stDegree/stDegreep if math.Abs(estimateJD-prevJD) <= 0.00001 { break } } return estimateJD } func VenusRiseTime(jd, lon, lat, tz, aeroCorrection, observerHeight float64) (float64, error) { return venusRiseDown(jd, lon, lat, tz, aeroCorrection, observerHeight, true) } func VenusSetTime(jd, lon, lat, tz, aeroCorrection, observerHeight float64) (float64, error) { return venusRiseDown(jd, lon, lat, tz, aeroCorrection, observerHeight, false) } func venusRiseDown(jd, lon, lat, tz, aeroCorrection, observerHeight float64, isRise bool) (float64, error) { return planetRiseDown(jd, lon, lat, tz, aeroCorrection, observerHeight, isRise, VenusCulminationTime, VenusHeight, VenusApparentDec) }