On 25 August 1609, Galileo Galilei demonstrated one of his early telescopes, with a magnification of about 8 or 9, to Venetian lawmakers. His telescopes were also a profitable sideline for Galileo selling them to merchants who found them useful both at sea and as items of trade. Read more
Galileo Galilei (15 February 1564 - 8 January 1642), was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. Read more
Galileo Galilei's drawings show that he first observed Neptune on December 28, 1612, and again on January 27, 1613. On both occasions, Galileo mistook Neptune for a fixed star when it appeared very close - in conjunction - to Jupiter in the night sky; hence, he is not credited with Neptune's discovery. Read more
Two fingers from Galileo's right hand and one of his teeth are now on display in a Florence museum after being deemed lost for more than a century. The fingers and tooth were removed - along with a third finger and a vertebra - from the astronomer's corpse on March 12, 1737, when his body was moved from the secret storage room where he had first been laid to the monumental tomb in the basilica of Florence's Santa Croce. Read more
Galileo was right. We know that now. But was he right to be right? There is a small, but respectable literature which argues that on the best scientific evidence available to him, he should have been a lot less confident of the truth of Copernican theory. This week's Nature carries an entertaining addition to the debate. A physicist in Kentucky, Christopher Graney, has worked out what Galileo could actually see through his telescope. He points out that the stars themselves were invisible: that Galileo could see were the diffraction patterns produced when light from a pinpoint source, such as a star is, seen from earth, enters a telescope. These are a lot larger than the stars themselves could be; this made the stars appear much closer to Galileo than in fact they are. All his reasoning is laid out in a paper here, by the way. It's not controversial. Read more
Galileo Galilei was right: Earth moves around the Sun, just as Nicolaus Copernicus said it did in 1543. But had Galileo followed the results of his observations to their logical conclusion, he should have backed another system - the Tychonic view that Earth didn't move, and that everything else circled around it and the Sun, as developed by Danish astronomer Tycho Brahe in the sixteenth century. This is the conclusion that Christopher Graney, a physicist at Jefferson Community and Technical College in Louisville, Kentucky, came to after reading manuscripts from another astronomer who was active in the late sixteenth and early seventeenth century, at the same time as Galileo. Read more
An art collector has found a tooth, thumb and finger of the renowned Italian scientist Galileo Galilei who died in the 17th century, Florence's History of Science museum announced on Friday. The body parts, along with another finger and a vertebrae, were cut from Galileo's corpse by scientists and historians during a burial ceremony held 95 years after his death in 1642.