\documentclass[12pt]{article}
\usepackage{pstricks}
\usepackage{pst-grad}
\usepackage{pst-vue3d}

\newpsstyle{GradGrayWhite}{fillstyle=gradient,%
    gradbegin=blue,gradend=white,linewidth=0.1mm}%

\begin{document}

\begin{pspicture}(-3.75,-3.25)(5,5.5)
	\AxesThreeD(45,40,50)
	\psset{PortionSphereTHETA=60,PortionSpherePHI=45,linewidth=0.1pt}
	\SphereThreeD[fillstyle=solid,fillcolor=cyan,linewidth=0.1pt](0,0,0){30}
	\PortionSphereThreeD[fillstyle=solid,fillcolor=red](0,0,0){30}
	\LineThreeD[SphericalCoor,linestyle=dashed](0,0,0)(30,70,35)
	\LineThreeD[SphericalCoor,linestyle=dashed](0,0,0)(30,50,35)
	\LineThreeD[SphericalCoor,linestyle=dashed](0,0,0)(30,70,55)
	\LineThreeD[SphericalCoor,linestyle=dashed](0,0,0)(30,50,55)
	\LineThreeD[SphericalCoor](30,70,35)(50,70,35)
	\LineThreeD[SphericalCoor](30,50,35)(50,50,35)
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	\LineThreeD[SphericalCoor](30,50,55)(50,50,55)
	\PortionSphereThreeD[fillstyle=solid,fillcolor=red](0,0,0){50}
	\psset{linestyle=dashed,linecolor=red,linewidth=\pslinewidth}
	\LineThreeD(0,0,0)(30,0,0)
	\LineThreeD(0,0,0)(0,30,0)
	\LineThreeD(0,0,0)(0,0,30)
\end{pspicture}

\begin{pspicture}(-3,-3.5)(3,5)%
  \psset{THETA=30,PHI=30,Dobs=100,Decran=10}%
  \SphereThreeD[fillstyle=solid,fillcolor=cyan,linewidth=0.1pt](0,0,0){20}
  \AxesThreeD(25)
  \PortionSphereThreeD[fillstyle=solid,fillcolor=gray](0,0,0){20}%
  \pNodeThreeD(20;10;10){C1}%
  \pNodeThreeD(40;10;10){D1}%
  \psline(C1)(D1)%
  \pNodeThreeD(20;10;-10){C2}%
  \pNodeThreeD(40;10;-10){D2}%
  \psline(C2)(D2)%
  \pNodeThreeD(20;-10;-10){C3}%
  \pNodeThreeD(40;-10;-10){D3}%
  \psline(C3)(D3)%
  \pNodeThreeD(20;-10;10){C4}%
  \pNodeThreeD(40;-10;10){D4}%
  \psline(C4)(D4)%
%
  \PortionSphereThreeD[style=GradGrayWhite](0,0,0){40}%
  \psset{linecolor=white,PhiCercle=45}%
  \SphereCercleThreeD(0,0,0){20}%
  \SphereMeridienThreeD[ThetaMeridien=45](0,0,0){20}%
  \SphereCercleThreeD[PhiCercle=0](0,0,0){20}%
  \SphereMeridienThreeD[THETA=30,PHI=30,ThetaMeridien=0](0,0,0){20}%
\end{pspicture}

\end{document}
