########################################################################################################## /lib/scripts/jqplot/jquery.jqplot.js /lib/scripts/jqplot/jquery.jqplot.css # css /lib/scripts/jqplot/jquery.min.js #(not required since DokuWiki 2012-01-25 Angua uses jQuery) /lib/scripts/jqplot/jquery.jqplot.min.js # js # # jsxgraph # https://cdn.jsdelivr.net/npm/jsxgraph/distrib/jsxgraphcore.js https://cdn.jsdelivr.net/npm/jsxgraph/distrib/jsxgraph.css # # personal # /lib/scripts/src/header.js /lib/scripts/src/pointCharge.js ############################################################################################################ ===== Lichtkurve Randverdunkelung (engl. limb darkening) ===== // NAMESPACE l var lbrd; var lonoff; var lbText = true; var lbImpact = true; var lbPlanet = true; var lxmin = -7.5; var lxmax = 7.5; var lplanet = 0.1; var limpact = 0.0; function lonInit() { writeMainHeader(); /////////////// BOARD lbrd = JXG.JSXGraph.initBoard('ljbox', {boundingbox: [-10, 10, 10, -10], axis:false, grid:false, showNavigation:false, showCopyright:false, needsRegularUpdate:true, unitX: 25, unitY: 25, originX:250, originY:250 }); //////////// STAR lstarRadius = 75/2 lbrd.create('point',[0,5], {face:'o', strokeColor: '#000', size:75, fixed: true, layer:8, fillColor: 'yellow', fillOpacity:0.5, needsRegularUpdate:true, name:'' } ); function limpactPosition(){ return -3*(limpact)+5;} lbrd.create('line',[[lxmin, 5],[lxmax,5]] ,{ needsRegularUpdate:true, strokeWidth:1, straightFirst:false, straightLast:false, strokeColor:'#D3D3D3'}); lbrd.create('line',[[lxmin, function(){ return limpactPosition()}],[lxmax, function() { return limpactPosition()}]] ,{ needsRegularUpdate:true, strokeWidth:1, straightFirst:false, straightLast:false, strokeColor:'#D3D3D3'}); function lplanetSize(){ return 2*lstarRadius*lplanet } /////// Impact //////////////////////////////////////////////////////////////// function lshowImpact0(){ if (lbText && lbImpact && limpact <= 0.4) return true; return false; } function lshowImpact04(){ if (lbText && lbImpact && limpact > 0.4) return true; return false; } lbrd.create('text',[-5.5,5.5,"b"],{ visible: function() { return lshowImpact0();},needsRegularUpdate:true}); lbrd.create('arrow', [ [-6,5+0.8],[-6,5]] ,{visible: function() {return lshowImpact0();},strokeColor:'#000'}); lbrd.create('arrow', [ [-6, function(){ return limpactPosition()-0.8}],[-6,function(){ return limpactPosition()}]] ,{ visible: function() {return lshowImpact0();}, strokeColor:'#000', stokeWidth: 1}); lbrd.create('text',[-5.5, function() {return 5-(5-limpactPosition())/2;},"b"],{ visible: function() { return lshowImpact04();},needsRegularUpdate:true}); lbrd.create('arrow', [ [-6,function() {return 5-(5-limpactPosition())/2;}],[-6,5]] , {visible: function() {return lshowImpact04();},strokeColor:'#000'}); lbrd.create('arrow', [ [-6,function() {return 5-(5-limpactPosition())/2;} ], [-6,function(){ return limpactPosition()}]] ,{visible: function() {return lshowImpact04();}, strokeColor:'#000', stokeWidth: 1}); /////////// R_p/ R_Star function lshowPlanet(){ if (lbText && lbPlanet) return true; return false; } function lplanetText(){ return 'R_p/R_* ≈ ' + lplanet.toFixed(2) + ' ' ; } function lplanetText1(){ if (lplanet <= 0.01 ){ return 'R_p/R_* ≈ R_{ERDE} ' ; } if (lplanet > 0.01 && lplanet < 0.10 ){ return 'R_p/R_* > R_{ERDE} ' ; } if (lplanet == 0.10 ){ return 'R_p/R_* ≈ R_{JUPITER} ' ; } if (lplanet > 0.10 ){ return 'R_p/R_* > R_{JUPITER} ' ; } } lbrd.create('text',[5,-5.5, function(){ return lplanetText();} ],{ visible: function() { return lshowPlanet();},needsRegularUpdate:true}); lbrd.create('text',[5,-7, function(){ return lplanetText1();} ],{ visible: function() { return lshowPlanet();},needsRegularUpdate:true}); // // //////////// planet lbrd.create('point',[ 0, function(){ return limpactPosition()}], {face:'o', strokeColor: '#000', size: function(){ return lplanetSize(); }, layer:8, fillColor: 'black', fillOpacity:0.7, needsRegularUpdate:true, name:'' } ); ///////// Koordinatensystem lbrd.create('arrow', [ [-8.7,-9],[-8.7,-1]] ,{strokeColor:'#000'}); lbrd.create('arrow', [ [-8.7,-9],[9,-9]] , {strokeColor:'#000'}); lbrd.create('text',[-9.2,-5,"Helligkeit"], { display: 'internal', rotate:90 }); lbrd.create('text',[8.5,-8.3,"Zeit"]); ////////// function lareaOfIntersection(x0, y0, r0, x1, y1, r1) { var rr0 = r0 * r0; var rr1 = r1 * r1; var d = Math.sqrt((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0)); // Circles do not overlap if (d > r1 + r0) { return 0; } // Circle1 is completely inside circle0 else if (d <= Math.abs(r0 - r1) && r0 >= r1) { // Return area of circle1 return Math.PI * rr1; } // Circle0 is completely inside circle1 else if (d <= Math.abs(r0 - r1) && r0 < r1) { // Return area of circle0 return Math.PI * rr0; } // Circles partially overlap else { var phi = (Math.acos((rr0 + (d * d) - rr1) / (2 * r0 * d))) * 2; var theta = (Math.acos((rr1 + (d * d) - rr0) / (2 * r1 * d))) * 2; var area1 = 0.5 * theta * rr1 - 0.5 * rr1 * Math.sin(theta); var area2 = 0.5 * phi * rr0 - 0.5 * rr0 * Math.sin(phi); // Return area of intersection return area1 + area2; } } var luniformDip = lbrd.create('functiongraph', [function(x){ x0 =0; y0 = 0; r0 = 75/2; y1 = limpact*37; x1 = 12.5*x; r1 = r0*lplanet; scale =-0.04; shift = -2; res = scale*lareaOfIntersection(x0, y0, r0, x1, y1, r1)+shift; return res; }, lxmin, lxmax ] ,{strokeWidth:3}); ////////////////////////////////////////////////////// } // END OF BLOCK function lbeschriftungChanged(value) { if (value.checked ){ lbText = true; }else { lbText = false ;} lbrd.fullUpdate(); } function lonoffChanged(source) { checkboxes = document.getElementsByName('lfoo'); for(var i=0, n=checkboxes.length;i
Idealisierte Lichtkurve zur Demonstration der Transitphasen. Bei der primären Phase läuft der Exoplanet vor dem Zentralgestirn und dem Beobachter vorbei, bei der sekundären Phase wird der Exoplanet vom Zentralgestirn verdeckt. Obwohl beide Phasen einen Lichtabfall erzeugen, stellt bereits die primäre Phase die Grenze des derzeit machbaren in der Amateurastronomie dar.
Einstellungen

Planet (rel. Größe):     

Impaktparameter b:     
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Der Impaktparamter b, hat einen wesentlichen Einfluss auf die Form der Lichtkurve. Der Parameter ist hier auf den Sternenradius skaliert, so dass der Planet bei einen Wert von $b=1$ einen partiellen Transit vollzieht.

Die Größenverhältnisse ($R_p/R_*$) zwischen Exoplanet und Zentralgestirn (engl. Hoststar), verändern die Form der Lichtkurve ebenfalls. Die Amateurastronomie muss sich (mit derzeitigen Amateurequipment) auf die großen Planeten konzentrieren, d.h. auf das Sonnensystem bezogen gilt: $R_J/R_* ≈ 0.1 $, da Jupiter der größte Planet im Sonnensystem ist.
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