Galileo Galilei's Anagram  In the 1610 there were two contradictory models for the universe. The incumbent model was the earth-centered universe of Claudius Ptolomias that had been accepted and had run like a complicated clock (with one tune up) for over 1400 years. The challenger was the sun-centered universe that Nicholas Copernicus proposed in 1543 . One of the details of the machinery of the Ptolemaic system was the motion of Venus around a circle (epicycle) with the center of this epicycle always lying between the earth and the sun. In the Copernican model, of course, Venus orbited the sun. In 1610 one of Galileo's former students (Benedetto Castelli) pointed out to him that: in the Ptolemaic model, Venus was always lighted from the side or behind; and therefore it should always appear crescent-shaped, as seen from the earth. In the Copernican model, on the other hand, Venus had a crescent shaped appearance when it was on the near side of the sun and a exhibited a nearly full (gibbous) phase when it was on the far side of the sun. For this reason when Venus came out in the morning sky in Oct. of 1610 Galileo was waiting with his telescope. When Galileo saw the gibbous phase for Venus he instantly knew he had in his hands the instrument for the destruction of the Ptolemaic universe. But Galileo also knew that anyone else with a telescope and the idea to look at Venus (e.g. Castelli) could scoop him. By Dec. of 1610, Venus had waned to a half lit phase and he could wait no longer. To gain some extra observing time Galileo published his results (in a letter to Kepler I believe) in a Latin anagram that he promised to unscramble later. Galileo's anagram was as follows. "Haec immatura a me iam frustra leguntur o.y." or "These are at present too young to be read by me" By New Years Day of 1611 Venus had moved around to the near side of the sun, it's crescent phase had begun to emerge, and Galileo unscrambled the anagram. "Cynthiae figuras aemulatur mater amorum" or "The mother of love imitates the shape of Cynthia" In plain words Venus (the mother of love) manifests all the phases that the Moon (Cynthia) goes through (and hence Venus must pass on both sides of the sun!!!). Galileo's observation absolutely proved the Ptolemaic system wrong. In subsequent years he published a full-blown refutation of the Ptolemaic system on many fronts. The church was not at all happy with this, since it had long adopted the Ptolemaic universe as part of it's dogma. Moreover, Galileo published in Italian, the language of the people, rather than Latin, the language of the scholars, thereby presenting an even more dangerous threat. The inquisition charged Galileo with "a vehement suspicion of heresy". After being shown the instruments of torture Galileo was forced to recant his work. He spent the last 9 years of his life under house arrest in his Villa near Florence, during which time he continued scientific work and received many important visitors. Galileo died in 1642 and was buried at church of Santa Croce (Florence) next to Michaelangelo & Machiavelli. The epitaph he had placed on his tombstone was "eppur Si muove" or "But the Earth does move!" Galileo had the last word after all ! In 1983 the Church cleared Galileo's name and in 1992 the Church apologizes & said it was wrong. Footnotes:  For more details see the "Galileo Affair" by O. Gingerich in Sci. Amer. (about 1981)  Actually the Greek astronomer Aristarchus proposed the sun-centered solar system about 280 B.C.. This allowed him to propose the explanation of the peculiar retrograde (backward) motion that the planets appear to execute in the night sky due to the fact that we are on a planet (earth), which is also in orbit about the sun. He also made estimates of the relative sizes of and distances between the earth, sun and moon. Copernicus did a very good job of putting the sun centered solar system together on a firmer quantative basis, however one must wonder where we might have been if mankind had not taken a 2000 year earth-centered detour.