<https://www.johanneskepler.info/keplers-facebook-page/>
<http://schema.org/description>
"Become a fan of the Kepler facebook page to keep up-to-date with Keplerian news or chat with Kepler fans from around the world including a number of Johan's living descendants and over 2000 followers."
<https://www.johanneskepler.info/keplers-facebook-page/>