De revolutionibus orbium coelestium have begun work on his new system by that time. Most historians believe that he wrote the "Commentariolus" after his return from Italy, possibly only after 1510. At this time, Copernicus anticipated that he could reconcile the motion of the Earth with the perceived motions of the planets easily, with fewer motions than were necessary in the "Alfonsine Tables", the version of the Ptolemaic system current at the time. In particular, the heliocentric Copernican model made use of the Urdi Lemma developed in the 13th century by Mu'ayyad al-Din al-'Urdi, the first of the Maragha astronomers to develop a non-Ptolemaic
The Fate of the Earth wonder, our wonder should make us humble, our humility should inspire us to reverence and caution, and our reverence and caution should lead us to act without delay to withdraw the threat we now pose to the earth and to ourselves." (p.95) The Fate of the Earth The Fate of the Earth is a 1982 book by Jonathan Schell. This "seminal" description of the consequences of nuclear war "forces even the most reluctant person to confront the unthinkable: the destruction of humanity and possibly most life on Earth". The book is regarded as a key document in the nuclear disarmament