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var canvas=document.getElementById("canvas");var cxt=canvas.getContext("2d");

function drawTrack(){for(var i=0;i<8;i++){

cxt.beginPath();

cxt.arc(500,500,50*(i+1),0,360,false);

cxt.closePath();

cxt.strokeStyle="#fff";

cxt.stroke();

}

}

drawTrack();

function Star(x,y,r,cycle,bColor,eColor){this.x=x;this.y=y;this.r=r;this.cycle=cycle;this.time=0;this.bColor=bColor;this.eColor=eColor;this.draw=function(){

cxt.save();

cxt.translate(500,500);

cxt.rotate(this.time*(360/this.cycle)*Math.PI/180);

cxt.beginPath();

cxt.arc(this.x,this.y,this.r,0,360,false);

cxt.closePath();var color=cxt.createRadialGradient(this.x,this.y,0,this.x,this.y,this.r);

color.addColorStop(0,this.bColor);

color.addColorStop(1,this.eColor);

cxt.fillStyle=color;

cxt.fill();

cxt.restore();this.time+=1;

}

}

function Sun(){

Star.call(this,0,0,20,0,"#FFFF00","#FF9900");

}

function Mercury(){

Star.call(this,0,-50,10,87.70,"#A69697","#5C3E40");

}

function Venus(){

Star.call(this,0,-100,10,224.701,"#C4BBAC","#1F1315");

}

function Earth(){

Star.call(this,0,-150,10,365.2422,"#78B1E8","#050C12");

}

function Mars(){

Star.call(this,0,-200,10,686.98,"#CEC9B6","#76422D");

}

function Jupiter(){

Star.call(this,0,-250,10,4332.589,"#C0A48E","#322222");

}

function Saturn(){

Star.call(this,0,-300,10,10759.5,"#F7F9E3","#5C4533");

}

function Uranus(){

Star.call(this,0,-350,10,30799.095,"#A7E1E5","#19243A");

}

function Neptune(){

Star.call(this,0,-400,10,60152,"#0661B2","#1E3B73");

}var sun=newSun();var mercury=newMercury();var venus=newVenus();var earth=newEarth();var mars=newMars();var jupiter=newJupiter();var saturn=newSaturn();var uranus=newUranus();var neptune=newNeptune();

function move(){

cxt.clearRect(0,0,1000,1000);

drawTrack();

sun.draw();

mercury.draw();

venus.draw();

earth.draw();

mars.draw();

jupiter.draw();

saturn.draw();

uranus.draw();

neptune.draw();

}

setInterval(move,10);