PHP has a function for calculating sunset and sunrise—for Earth


<?php
$sun = date_sun_info(time(), 51.50, -0.127);
var_dump( $sun );
?>
Output
array(9) { ["sunrise"]=> int(1772778758) ["sunset"]=> int(1772819449) ["transit"]=> int(1772799104) ["civil_twilight_begin"]=> int(1772776863) ["civil_twilight_end"]=> int(1772821344) ["nautical_twilight_begin"]=> int(1772774546) ["nautical_twilight_end"]=> int(1772823661) ["astronomical_twilight_begin"]=> int(1772772194) ["astronomical_twilight_end"]=> int(1772826013) }