Re: Sphere

*To*: mathgroup at smc.vnet.net*Subject*: [mg65548] Re: Sphere*From*: dh <dh at metrohm.ch>*Date*: Fri, 7 Apr 2006 06:14:24 -0400 (EDT)*References*: <e12s6o$j7i$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Hi Matija, If you are happy with longitude and lattitude, we may simply map the rectangular parameter space: phi=0..2Pi and theta=-P/2...Pi/2 onto the sphere. Here is an example. Define some curve, here a loxodrome: phi[x_]:=6 x; theta[x_]:= Mod[x,Pi]-Pi/2; here is the map: mymap[phi_,theta_]:={Cos[theta] Cos[phi],Cos[theta] Sin[phi], Sin[theta]} here is the drawing: << Graphics`Shapes` Show[Graphics3D[{ Sphere[1, 20, 20], Thickness[0.01], Line[ Table[mymap[phi[x], theta[x]], {x, 0, 2Pi, 0.01}] ] }], AmbientLight -> GrayLevel[0.9], LightSources -> {}] here is the same curve in parameterspace (phi axes extended): ParametricPlot[{phi[x], theta[x]}, {x, 0, Pi}] Daniel Matija Herceg wrote: > Hi, > > My professor ask me if I could make program which would draw celestial > sphere with (celestial) measurements on it to show celestial coordinates > of some (celestial) body. > > My idea was that I could draw sphere in mathematica, and with celestial > coordinates given by user input the program would draw celestial curves > (declination, ascension...). > > Can I draw curves on sphere in Mathematica? > > Is this possible in new version of Mathematica (5.1 and higher)? > Because GeometricalGeodesy (a new Mathematica application package) is > now available, and I don't know if some of this problems can be solved > without this new package. > > Thanks, > > Matija >