Kinematics - Galileo

• It started with Galileo disagreeing with the Jesuit monk
Orazzio Grassi, about the nature and the orbit of the comet
of 1619. Grassi insisted that the comet was closer than the
Moon (according to Aristotelian views), Galileo calculated
that it was further away.
• There was an “escalation” in exchanging arguments from
both sides (books and pamphlets published under a “nom
de plume” or written by “followers” of each side).
• The debate reached a climax with the publication of the
book Il Saggiatore (assayer=tester, a kind of stone used to
measure content in gold of an alloy ), written in Italian and
not in Latin, where Galileo brings forth all arguments for
the heliocentric theory and ridicules openly Grassi and his
other opponents.
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