<sect2 id="calc-dayduration">
<title
>Day Duration module</title>
<indexterm
><primary
>Tools</primary>
<secondary
>Astrocalculator</secondary>
<tertiary
>Day Duration module</tertiary>
</indexterm>

<screenshot>
<screeninfo
>The Day Duration calculator module </screeninfo>
<mediaobject>
  <imageobject>
    <imagedata fileref="calc-daylength.png" format="PNG"/>
  </imageobject>
  <textobject>
    <phrase
>Day Duration</phrase>
  </textobject>
</mediaobject>
</screenshot>

<para
>This module computes the length of day as well as sunrise, sun-transit (noon), and sunset times for any calendar date, for any location on Earth. First fill in the desired geographic coordinates and date, then press the <guibutton
>Compute</guibutton
> button. </para>
</sect2>