Area of a circle segment on sphere (Earth) given central coordinates (lat / long), radius (meters) and central angle (degrees) : <h2>Situation</h2>

<p>I have a circle segment and some information about the circle it belongs to.</p>

<p>Given Information:</p>

<ul>
<li><strong>coordinates of the center</strong> of the circle (latitude / longitude)</li>
<li><strong>radius</strong> of the circle in meters</li>
<li><strong>central angle</strong> in degrees</li>
</ul>

<p>I need to calculate the <strong><code>area</code></strong> of the circle segment in JavaScript. But it should also depend on the radius of the Earth <em>(like <a href="https://en.wikipedia.org/wiki/Great-circle_distance" rel="nofollow noreferrer">great-circle distance</a>)</em>.</p>

<h2>Problem</h2>

<p>I have no idea how to do that and couldn't found any algorithms.</p>

<p>Thanks for help</p>
