"OG" wrote in message
...

Thierry wrote in message ...
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...

Looks like the dates may be in error
Wikipedia
"Based only on sketchy descriptions of the telescope, invented in the
Netherlands in 1608, Galileo made one with about 8x magnification, and
then made improved models up to about 20x. On August 25, 1609, he
demonstrated his first telescope to Venetian lawmakers."

Right. My mistake. I reread , my notes (I always wonder of the number of
information i found on my own site and that I have forgotten, of almost).
Hopefully there is a search engine....
Galileo seems have demonstrated his scope already on August 21. Its
magnification was 3x.
Remain to confirm the first observation of venus and with what scope

Thierry