When I was a child, there was a French animated series called “The Secret of the Selenites”. The story was captivating: in 1787, the astrologer Sirius, convinced of the existence of the Selenites, set off on an expedition to the Moon with his cousin, Baron Munchausen. The two men and their crew landed and discovered the Selenites, immortal beings who hold the Secret of Eternal Life.

The first part is dedicated to what I imagine to be the secret: a clepsydra that contains our heart and must be constantly turned to keep us alive.