dec 30, 1610 - Galileo uses/Invents "SpyGlass"
Description:
What galileo called a spyglass was actually his design of the Refracting telescope
<How A Refractor Works>
"Light enters a refracting telescope through a lens at the upper end, which focuses the light near the bottom of the telescope. An eyepiece then magnifies the image so that it can be viewed by the eye, or a detector like a photographic plate can be placed at the focus."
(Astronomy Text)
Added to timeline:
Technology timeline of astronomy
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