Likewise, Saturn and the other planets reflect sunlight, and that's why we can see them in the night sky. If our sun did not shine, we would still see all the stars at night, but the planets would be invisible to us.

Like the other planets, Saturn is cool and radiates its own light at infrared wavelengths, as seen here on the left in an HST image.

People are solid bodies with a temperature of 98 °F, and we emit light, too, but just not at wavelengths that our eyes can see.