Galileo didn't invent the telescope. Actually, he was far from the first person to own one - records show that even the Pope probably had one before he did! What was different was the high magnification of his instrument.
All of this started because of a 1608 patent application by Hans Lipperhey for a spyglass "with which one can see all things very far away as if they were nearby". Through the combination of two lenses, he achieved magnifications between 3X to 4X. Lipperhey wrote to the noblemen in The Hague, and was invited to demonstrate his instrument, capable of "seeing all things very far away as if they were nearby". Two weeks later, at least two more people came forward claiming they had also invented the telescope. Immediately, people all over the continent understood the wartime advantage of owning one, for example: counting the number of archers stationed at a wall before your siege begins. So there were a wealth of pre-Galilean telescopes - Galileo's contribution was his improvement to high powered optics (21X magnification), and his consistent, detailed observations of the sky, which he conducted in the years 1609 and 1610.
Today we are visiting Sterrenwacht Middelburg, situated around the corner from the home where Lipperhey invented his spyglass. Middelburg is known worldwide as the birthplace of this invention. The observatory houses some powerful instruments as well as some important ones. Rijk-Jan, one of the astronomers, invited us for some coffee and to share a conversation about sidewalk astronomy. The Dutch people are overall very familiar with astronomy. The University at Leiden exports astronomers all over the world. SterrenWacht Middelburg does a number of events outside town hall: with Dobsonians, with solar telescopes: the best time to show someone the Universe is when they are simply walking by.
A small room houses a 16" Meade Schmidt-Cassegrain, staring out the window toward the southern sky. Unfortunately due to its location, the window overlooks some lights and windows which must ruin the astronomy. That's when Rijk-Jan shows me something I've never seen before. He flips a circuit breaker on an electrical box next to the telescope, and every street lamp in view of the telescope simply turns off! Astronomers who are reading, imagine the trust and opportunity to work so closely with town officials for that!
The Philly Moon Men advocate about light pollution, and actually, due to its dense population, the Netherlands has some of the worst light pollution in all of Europe. Its cities are comparable to New York or Philadelphia. Still, in the smaller town of Middelburg, the constellations are visible.
Rijk-Jan takes us to display cases with mannequins of Galileo and Hans Lepperhey. He opens up the display with his key, and robs the mannequin of his prop. The prop is actually a French refractor built in the year 1690. He allows us to hold it, and shows us some features of its design. The telescope has a third lens inside, called a field lens, that provides an upright image to the user. With a field lens inside a telescope, if you look at mountains, the mountains are not upside-down. The field lens is removeable as well, so that the telescope can be used at night-time in low light conditions.
We return to the coffee shop, and Rijk-Jan gives us a book that will turn me into a quick expert on telescopes. A thick text "The Origins of the Telescope", filled with all the evidence and debate of just how this important device came into existence. Thank you to all the astronomers at SterrenWacht Middelburg for helping us with our education!
Next we walk outside to the old foundations of Lipperhey's home. From this site, we use the old French refractor to look at the wind vane on top of the Abbey, just as, according to legend, Hans Lipperhey did over 400 years ago. The refractor in Rijk-Jan's hand represents already 80 years of innovation over Lipperhey's invention. The field of view is quite small, but the clarity of the image is surprising, with a bit of chromatic aberration but nothing that gets in the way of making an observation.
Feeling inspired, Rijk-Jan decides to take the ancient telescope home for an evening, and make a sketch of the telescope.
The next time you visit a science museum and see a telescope hanging in a display case, remember that it probably still works!