Episode23: Telescopes before Galileo? Part 1

Hans Lipperhey's patent application in the Netherlands for a
telescope was formally denied on 2nd October 1608. Nonetheless, it
is that individual, that place and that date which history
associates with the invention of the telescope. Most of us are
aware of the fundamental astronomical discoveries Galileo went on
to make with it in the following year but could they have been made
earlier? Three thousand years ago, in what today is  Iraq ,
the  Nimrud lens now in the British Museum is clearly
recognised as a lens. It probably could not have been used as part
of an astronomical telescope but it is evidence that strongly
indicates that lenses were in use long before Lipperhey and
Galileo. The Pharos lighthouse in Alexandria is another
illlustration of the advance understanding of optics in ancient
times. Chris Lord is an accomplished amateur astronomer and member
of Blackpool & District Astronomical Society. He has recently
completed a major piece of research in telescopes and optics to
mark the International Year of Astronomy in 2009. In this Episode,
Chris talks about at the theory of vision, optics and the making
and use of lenses during the almost two centuries from Euclid to
Galileo.