Umrechnung von Horizontalkoordinaten (Höhe und Azimut) in
Aequatorialkoordinaten (Deklination und Stundenwinkel)

geogrBreite  :=  30.0;

dStdLin  :=  7.5;

phi :=  geogrBreite*Degree;

\(\(

\)\)

\(\(		
    x := \ Function[{hDeg, aDeg}, \ 
		
				a := aDeg\ \ Degree; 

        				h := hDeg\ Degree; 
				x0 := Cos[h]*Cos[a]; 
				
        y0 := Cos[h]*Sin[a]; 
				z0 := Sin[h]; 
				
        x1 := z0*Cos[phi] + x0*Sin[phi]; 
				y1 := \ y0; 
				
        z1 := \ z0*Sin[phi] - x0*Cos[phi]; 
				zd\  := \ ArcCos[z1]; 

        				d := ArcSin[z1]; 
				cosT\  := \ x1/Cos[d]; 
				
        sinT\  := \ y1/Cos[d]; 
		
		zd*sinT\ \ \ \ ]

\)\)

\(\(		
    y := \ Function[{hDeg, aDeg}, \ 
		
		a := aDeg\ \ Degree; 
		
        h := hDeg\ Degree; 
		x0 := Cos[h]*Cos[a]; 
		
        y0 := Cos[h]*Sin[a]; 
		z0 := Sin[h]; 
		
        x1 := z0*Cos[phi] + x0*Sin[phi]; 
		y1 := \ y0; 
		
        z1 := \ z0*Sin[phi] - x0*Cos[phi]; 
		zd\  := \ ArcCos[z1]; 
		
        d := ArcSin[z1]; 
		cosT\  := \ x1/Cos[d]; 
		
        sinT\  := \ y1/Cos[d]; 
		
		zd*cosT\ \ \ \ ]\)\)

\(\(					
	
\)\)

\(g0 = 
      ParametricPlot[{{x[0, t], \ y[0, t]}, \ 

          																			{x[10, t], \ y[10, t]}, 

          																			{x[20, t], \ y[20, t]}, 

          																			{x[30, t], \ y[30, t]}, 

          																			{x[40, t], \ y[40, t]}, 

          																			{x[50, t], \ y[50, t]}, 

          																			{x[60, t], \ y[60, t]}, 

          																			{x[70, t], \ y[70, t]}, 

          																			{x[80, t], \ y[80, t]}, 

          																			{x[t/4, 0], \ y[t/4, 0]}\ , 

          																			{x[t/\((360/70)\), 7.5], \ 
            y[t/\((360/70)\), 7.5]}\ , 

          																			{x[t/\((360/70)\), \(-7.5\)], 
            \ y[t/\((360/70)\), \(-7.5\)]}\ , 

          																			{x[t/\((360/80)\), 15], \ 
            y[t/\((360/80)\), 15]}\ , 

          																			{x[t/\((360/80)\), \(-15\)], 
            \ y[t/\((360/80)\), \(-15\)]}\ , 

          																			{x[t/\((360/70)\), 22.5], \ 
            y[t/\((360/70)\), 22.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-22.5\)], \ y[t/\((360/70)\), \(-22.5\)]}\ , 
          
																			{x[t/\((360/80)\), 30], \ 
            y[t/\((360/80)\), 30]}\ , 

          																			{x[t/\((360/80)\), \(-30\)], 
            \ y[t/\((360/80)\), \(-30\)]}\ , 

          																			{x[t/\((360/70)\), 37.5], \ 
            y[t/\((360/70)\), 37.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-37.5\)], \ y[t/\((360/70)\), \(-37.5\)]}\ , 
          
																			{x[t/\((360/80)\), 45], \ 
            y[t/\((360/80)\), 45]}\ , 

          																			{x[t/\((360/80)\), \(-45\)], 
            \ y[t/\((360/80)\), \(-45\)]}\ , 

          																			{x[t/\((360/70)\), 52.5], \ 
            y[t/\((360/70)\), 52.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-52.5\)], \ y[t/\((360/70)\), \(-52.5\)]}\ , 
          
																			{x[t/\((360/80)\), 60], \ 
            y[t/\((360/80)\), 60]}\ , 

          																			{x[t/\((360/80)\), \(-60\)], 
            \ y[t/\((360/80)\), \(-60\)]}\ , 

          																			{x[t/\((360/70)\), 67.5], \ 
            y[t/\((360/70)\), 67.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-67.5\)], \ y[t/\((360/70)\), \(-67.5\)]}\ , 
          
																			{x[t/\((360/80)\), 75], \ 
            y[t/\((360/80)\), 75]}\ , 

          																			{x[t/\((360/80)\), \(-75\)], 
            \ y[t/\((360/80)\), \(-75\)]}\ , 

          																			{x[t/\((360/70)\), 82.5], \ 
            y[t/\((360/70)\), 82.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-82.5\)], \ y[t/\((360/70)\), \(-82.5\)]}\ , 
          
																			{x[t/4, 90], \ y[t/4, 90]}, 
          
																			{x[t/4, \(-90\)], \ 
            y[t/4, \(-90\)]}, 

          																			{x[t/\((360/70)\), 97.5], \ 
            y[t/\((360/70)\), 97.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-97.5\)], \ y[t/\((360/70)\), \(-97.5\)]}\ , 
          
																			{x[t/\((360/80)\), 105], \ 
            y[t/\((360/80)\), 105]}\ , 

          																			{x[t/\((360/80)\), \(-105\)], 
            \ y[t/\((360/80)\), \(-105\)]}\ , 

          																			{x[t/\((360/70)\), 112.5], \ 
            y[t/\((360/70)\), 112.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-112.5\)], \ y[t/\((360/70)\), \(-112.5\)]}
            \ , 
																			{
            x[t/\((360/80)\), 120], \ y[t/\((360/80)\), 120]}\ , 

          																			{x[t/\((360/80)\), \(-120\)], 
            \ y[t/\((360/80)\), \(-120\)]}\ , 

          																			{x[t/\((360/70)\), 127.5], \ 
            y[t/\((360/70)\), 127.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-127.5\)], \ y[t/\((360/70)\), \(-127.5\)]}
            \ , 
																			{
            x[t/\((360/80)\), 135], \ y[t/\((360/80)\), 135]}\ , 

          																			{x[t/\((360/80)\), \(-135\)], 
            \ y[t/\((360/80)\), \(-135\)]}\ , 

          																			{x[t/\((360/70)\), 142.5], \ 
            y[t/\((360/70)\), 142.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-142.5\)], \ y[t/\((360/70)\), \(-142.5\)]}
            \ , 
																			{
            x[t/\((360/80)\), 150], \ y[t/\((360/80)\), 150]}\ , 

          																			{x[t/\((360/80)\), \(-150\)], 
            \ y[t/\((360/80)\), \(-150\)]}\ , 

          																			{x[t/\((360/70)\), 157.5], \ 
            y[t/\((360/70)\), 157.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-157.5\)], \ y[t/\((360/70)\), \(-157.5\)]}
            \ , 
																			{
            x[t/\((360/80)\), 165], \ y[t/\((360/80)\), 165]}\ , 

          																			{x[t/\((360/80)\), \(-165\)], 
            \ y[t/\((360/80)\), \(-165\)]}\ , 

          																			{x[t/\((360/70)\), 172.5], \ 
            y[t/\((360/70)\), 172.5]}\ , 

          																			{
            x[t/\((360/70)\), \(-172.5\)], \ y[t/\((360/70)\), \(-172.5\)]}
            \ , 
																			{x[t/4, 180], \ 
            y[t/4, 180]}\ }, 
															{t, 0, 360}, 

        							AspectRatio -> 1, 
							
        PlotPoints\  -> \ 180, 
							Axes\  -> \ True, 

        							Ticks\  -> \ None, 
							
        GridLines\  -> \ None, 
							
        PlotRange\  -> \ {{\(-2.5\), 2.5}, {\(-2.5\), 2.5}}, 
							
        PlotStyle -> {AbsoluteThickness[0.5], RGBColor[0, 0, 0]}


        			\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ]
        \)

\(g1 = 
      ParametricPlot[{2.4\ Sin[t], 2.4\ Cos[t]}, {t, 0, 2\ Pi}, 
		
        PlotPoints\  -> \ 180]\)

\(g2 = 
      ParametricPlot[
        \ {{x[\(-6\), t], y[\(-6\), t]}, {x[\(-6\), \(-t\)], \ 
            y[\(-6\), \(-t\)]}}, 
		{t, 55, 138}, 
		
        PlotPoints\  -> \ 180]\)

\(g3 = 
      ParametricPlot[
        \ {{x[\(-12\), t], y[\(-12\), t]}, {x[\(-12\), \(-t\)], \ 
            y[\(-12\), \(-t\)]}}, {t, 60, 150}, 
		PlotPoints\  -> \ 180]
        \)

\(g4 = 
      ParametricPlot[
        \ {{x[\(-18\), t], y[\(-18\), t]}, {x[\(-18\), \(-t\)], \ 
            y[\(-18\), \(-t\)]}}, {t, 68, 175}, 
		PlotPoints\  -> \ 180]
        \)

Show[g0, g1, g2, g3, g4]

\(g0 = 
      ParametricPlot[{
			\ \ \ \ \ \ \ \ \ {x[0, t], \ y[0, t]}, 

          						\ \ {x[t/4, 0], \ y[t/4, 0]}\ , 

          						\ \ {x[t/4, 90], \ y[t/4, 90]}, 

          						\ \ {x[t/4, 270], \ y[t/4, 270]}, 

          						\ \ {x[t/4, 180], \ y[t/4, 180]}\ \ \ \ \ \ \ \ \ \ }, 
        
		
						\ \ {t, 0, 360}, 
							
        AspectRatio -> 1, 
							PlotPoints\  -> \ 180, 

        							Axes\  -> \ False, 
							Ticks\  -> \ None, 

        							GridLines\  -> \ None, 
							
        PlotRange\  -> \ {{\(-2.5\), 2.5}, {\(-2.5\), 2.5}}, 
							
        PlotStyle -> {AbsoluteThickness[1.0]}


        			\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ]
        \)