Kepler's Laws Ellipse

KeplerEllipse2.svg

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<svg viewBox="0 0 300 200" xmlns="http://www.w3.org/2000/svg">
<defs>
<marker id="ar" refX="8" refY="4" orient="auto"
markerWidth="10" markerHeight="10" markerUnits="strokeWidth">        
<path d="M 1 1 L 8 4 L 1 7" 
style="fill:none; stroke:#000; stroke-linejoin:bevel"/>    
</marker>
</defs>   
<rect width="100%" height="100%" fill="#fff"/>
<g transform="translate(150,100)">
<path d="M 60.0000 0 L 90.0944 34.7149 A 100 80 0 0 0 90.0944 -34.7149 Z" fill="cyan"/>
<path d="M 100 0 A 100 80 0 0 0 90.0944 -34.7149" style="fill:none; marker-mid:url(#ar)"/>
<path d="M 60.0000 0 L -99.3056 -9.4111 A 100 80 0 0 0 -99.3056 9.4111 Z" fill="cyan"/>
<path d="M -100 0 A 100 80 0 0 0 -99.3056 9.4111" style="fill:none; marker-mid:url(#ar)"/>
<circle cx="60.0000" r="8" fill="#fd0" stroke="#ca0"/>
<ellipse rx="100" ry="80" style="fill:none; stroke:#000"/>
<g style="font-family:serif; font-size:12;">
<text x="108" y="5">Faster</text>
<text x="-108" y="5" style="text-anchor:end">Slower</text>
<text x="0" y="-35" style="text-anchor:middle">Blue areas equal</text>
</g>
</g>
</svg>

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