show the "tail-end of the solar cycle" with instrumentation before the telescope was more widely available in the early 17th century. "The group's findings … offer a key to resolving the ...

While there are several stories behind how the telescope came to be, the most settled upon one involves Dutch glassmaker Hans Lippershey in the 17th century (via Space.com). Glassmakers had been ...

The first telescopes, known as refracting telescopes, were built in the early 17th century by Dutch eyeglass makers. They employed a pair of lenses—one convex fitted at the end of the scope ...

When Italian astronomer Galileo Galilei heard rumors of the first practical telescope at the beginning of the 17th century, he was quick to craft his own version and turn it toward the heavens.

"The group's findings … offer a key to resolving the controversy on the duration of solar cycles at the beginning of the 17th century ... Since Kepler lacked the telescope, he instead examined ...