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astro/basic/coordinate.go

142 lines
4.0 KiB
Go

5 years ago
package basic
import (
"math"
. "b612.me/astro/tools"
)
/*
*
*/
func LoToRa(lo, bo, jde float64) float64 {
ra := math.Atan2(Sin(lo)*Cos(Sita(jde)-Tan(bo)*Sin(Sita(jde))), Cos(lo))
ra = ra * 180 / math.Pi
if ra < 0 {
ra += 360
}
return ra
}
func BoToDec(lo, bo, jde float64) float64 {
dec := ArcSin(Sin(bo)*Cos(Sita(jde)) + Cos(bo)*Sin(Sita(jde))*Sin(lo))
return dec
}
/*
* st end JDE
*/
func ZuoBiaoSuiCha(ra, dec, st, end float64) (float64, float64) {
t := (end - st) / 36525.0
l := (2306.2181*t + 0.30188*t*t + 0.017998*t*t*t) / 3600
z := (2306.2181*t + 1.09468*t*t + 0.018203*t*t*t) / 3600
o := (2004.3109*t - 0.42665*t*t + 0.041833*t*t*t) / 3600
A := Cos(dec) * Sin(ra+l)
B := Cos(o)*Cos(dec)*Cos(ra+l) - Sin(o)*Sin(dec)
C := Sin(o)*Cos(dec)*Cos(ra+l) + Cos(o)*Sin(dec)
ras := math.Atan2(A, B)
ras = ras * 180 / math.Pi
if ras < 0 {
ras += 360
}
ra = ras + z
dec = ArcSin(C)
return ra, dec
}
/*
* jdeau
*/
func pcosi(lat, h float64) float64 {
b := 6356.755
a := 6378.14
u := ArcTan(b / a * Tan(lat))
//psin=b/a*Sin(u)+h/6378140*Sin(lat);
pcos := Cos(u) + h/6378140.0*Cos(lat)
return pcos
}
func psini(lat, h float64) float64 {
b := 6356.755
a := 6378.14
u := ArcTan(b / a * Tan(lat))
psin := b/a*Sin(u) + h/6378140*Sin(lat)
//pcos=Cos(u)+h/6378140*Cos(lat);
return psin
}
func ZhanXinRaDec(ra, dec, lat, lon, jd, au, h float64) (float64, float64) {
sinpi := Sin(0.0024427777777) / au
pcosi := pcosi(lat, h)
psini := psini(lat, h)
tH := Limit360(TD2UT(SeeStarTime(jd), false)*15 + lon - ra)
nra := math.Atan2(-pcosi*sinpi*Sin(tH), (Cos(dec)-pcosi*sinpi*Cos(tH))) * 180 / math.Pi
ndec := math.Atan2((Sin(dec)-psini*sinpi)*Cos(nra), (Cos(dec)-pcosi*sinpi*Cos(tH))) * 180 / math.Pi
return ra + nra, ndec
}
func ZhanXinRa(ra, dec, lat, lon, jd, au, h float64) float64 { //jd为格林尼治标准时
sinpi := Sin(0.0024427777777) / au
pcosi := pcosi(lat, h)
tH := Limit360(TD2UT(SeeStarTime(jd), false)*15 + lon - ra)
nra := math.Atan2(-pcosi*sinpi*Sin(tH), (Cos(dec)-pcosi*sinpi*Cos(tH))) * 180 / math.Pi
return ra + nra
}
func ZhanXinDec(ra, dec, lat, lon, jd, au, h float64) float64 { //jd为格林尼治标准时
sinpi := Sin(0.0024427777777) / au
pcosi := pcosi(lat, h)
psini := psini(lat, h)
tH := Limit360(TD2UT(SeeStarTime(jd), false)*15 + lon - ra)
nra := math.Atan2(-pcosi*sinpi*Sin(tH), (Cos(dec)-pcosi*sinpi*Cos(tH))) * 180 / math.Pi
ndec := math.Atan2((Sin(dec)-psini*sinpi)*Cos(nra), (Cos(dec)-pcosi*sinpi*Cos(tH))) * 180 / math.Pi
return ndec
}
func ZhanXinLo(lo, bo, lat, lon, jd, au, h float64) float64 { //jd为格林尼治标准时
C := pcosi(lat, h)
S := psini(lat, h)
sinpi := Sin(0.0024427777777) / au
ra := LoToRa(lo, bo, jd)
tH := Limit360(TD2UT(SeeStarTime(jd), false)*15 + lon - ra)
N := Cos(lo)*Cos(bo) - C*sinpi*Cos(tH)
nlo := math.Atan2(Sin(lo)*Cos(bo)-sinpi*(S*Sin(Sita(jd))+C*Cos(Sita(jd))*Sin(tH)), N) * 180 / math.Pi
return nlo
}
func ZhanXinBo(lo, bo, lat, lon, jd, au, h float64) float64 { //jd为格林尼治标准时
C := pcosi(lat, h)
S := psini(lat, h)
sinpi := Sin(0.0024427777777) / au
ra := LoToRa(lo, bo, jd)
tH := Limit360(TD2UT(SeeStarTime(jd), false)*15 + lon - ra)
N := Cos(lo)*Cos(bo) - C*sinpi*Cos(tH)
nlo := math.Atan2(Sin(lo)*Cos(bo)-sinpi*(S*Sin(Sita(jd))+C*Cos(Sita(jd))*Sin(tH)), N) * 180 / math.Pi
nbo := math.Atan2(Cos(nlo)*(Sin(bo)-sinpi*(S*Cos(Sita(jd))-C*Sin(Sita(jd))*Sin(tH))), N) * 180 / math.Pi
return nbo
}
/*
func GXCLo(lo,bo,jd float64) float64{ //光行差修正
k:=20.49552;
sunlo:=SunTrueLo(jd);
e:=Earthe(jd);
epi=earth->EarthPI(jd);
tmp=(-k*this->CosR(sunlo-lo)+e*k*this->CosR(epi-lo))/this->CosR(bo);
return tmp;
}
public function GXCBo(lo,bo,jd)
{
earth=new Earth();
k=20.49552;
sunlo=earth->SunTrueLo(jd);
e=earth->Earthe(jd);
epi=earth->EarthPI(jd);
tmp=-k*this->SinR(bo)*(this->SinR(sunlo-lo)-e*this->SinR(epi-lo));
return tmp;
}
*/