<?xml version="1.0" encoding='utf-8'?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="card1" title="Libration - Page 16 - Wikipedia">
<p>
<a accesskey="1" href="page.php?w=Libration&amp;p=15">1.Previous</a><br />
<a accesskey="3" href="page.php?w=Libration&amp;p=17">3.Next</a>
</p>

<p>The placement of three retroreflectors on the Moon by the <a href="page.php?w=Lunar_Laser_Ranging_experiment">Lunar Laser Ranging experiment</a> and two retroreflectors by <a href="page.php?w=Lunokhod_programme">Lunokhod</a> rovers allowed accurate measurement of the physical librations by laser ranging to the Moon.</p>

<p><big> Free physical libration </big></p>
<p>A free physical libration is similar to the solution of the reduced equation for linear differential equations. The periods of the free librations can be calculated, but their amplitudes</p><p>
<a accesskey="1" href="page.php?w=Libration&amp;p=15">1.Previous</a><br />
<a accesskey="3" href="page.php?w=Libration&amp;p=17">3.Next</a>
</p>

<do type="prev" label="Search">
        <go href="search.wml"/>
</do>

</card>
</wml>
