|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
galileo galilei - dates to confirm
Hello,
A question about historical truth. It is said that Galileo discovered the phases of Venus phases in 1610. OK. It is also said that he invented his scope only in 1610 Two dates to be confirmed, and if possible in the month close... If I simulate the sky at that time, of Firenze, arcetri, we discover that in Jan-April 1610 Venus was in the East, 10° over the horizon with 80%+ illuminated, thus very small, and at the end in the rays of sun. hard to imagine that he observed it at that time. It nevertheless could have did it. On the other hand, at the autumn 1609 venus shows a fine crescent, and was higher in the sky of the morning Idem from October 1610 but, this time in the eve. However it would have published his Siderius Nuncius in March 1610 (also to re-confirm). Impossible thus that he observed the beautiful crescent of venus before publishing his book. It was thus to have written his explanation and signed the "go for printing", say at least 1 month before, in February If one assumes that it was very smart, it obviously could have interpreted the phases right between the invention of his scope and February 1610. But that leaves him just a few weeks, and in counting on clear sky every days, to discover the phases and its explanations, under bad seeing, without speaking about his optics.... The book having been published in March, he would thus have observed Venus at the worst moment of its phase Or he had to develop his scope in 1609... But here also, the first drafts of Giovanni Battista della Porta were published in August 1609... (to confirm as well). But that of Galileo would not have been invented yet at that time. That would tend to confirm that Galileo would have discovered the Venus phases at a time it had a small diameter ( 15-12" if I remember well) under very difficult conditions (both hardware and astronomical). The discovery would all the more be deserving. But is this well at that time that all that was held ? Who could find me the exact dates (invention of Galileo's scope, 1st obs., obser. of Venus phases, publication of Messenger, etc) Thanks in avdance Thierry http://www.astrosurf.org/lombry |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
28 December 2005 : New step for the Galileo System | POLE STAR | Policy | 2 | December 30th 05 11:24 AM |
First Galileo satellite on orbit to demonstrate key technologies(Forwarded) | Andrew Yee | News | 0 | December 30th 05 01:15 AM |
Galileo End of Mission Status | Ron Baalke | History | 65 | October 30th 03 02:31 PM |
Galileo End of Mission Status | Ron Baalke | Astronomy Misc | 15 | October 10th 03 04:19 AM |
The Final Day on Galileo | Ron Baalke | Science | 0 | September 19th 03 07:32 PM |