"All truths are easy to understand once they are discovered; the point is to discover them."
— Galileo Galilei 
Some amateur astronomers regard telescopes with small apertures with disdain, complaining that they cannot gather enough light to find anything in the night sky but maybe the moon, planets, and a few bright stars. But telescopes with relatively modest apertures made and used by Galileo Galilei shook the very foundation of science and religion.
Although Galileo did not invent the telescope, his small telescopes ushered in modern astronomy. His designs were improved to give more magnification producing up to about 30 power. And although he may not have been the first to use a telescope to observe celestial objects, he faithfully recorded what he observed, and he had many correct insights into the nature of the universe as we know it today.
Galileo made many telescopes, but only one of his telescope lenses survives today — a biconvex objective lens with an effective diameter of only 38mm. It was used in his telescope for many observations from 1609 to 1610. And it was in 1610 he observed, recorded, and published the amazing discovery of Jupiter's moons as they orbited the giant planet in his book "Sidereus Nuncius".
Galileo donated the lens of the telescope with which he made the discovery of Jupiter's moons to Grand Duke Ferdinand II. Unfortunately, it was accidentally broken only a few years later. After Galileo died in 1642 the lens was kept by Leopold de' Medici, who died in 1675. Thereafter it was jealously guarded at the Uffizi Gallery until 1793, when it was transferred to the Museo di Fisica e Storia Naturale (http://www.msn.unifi.it/). In the mid-nineteenth century, the lens was displayed in the Tribuna di Galileo with other Galilean memorabilia. In 1677, the Medici commissioned Vittorio Crosten to build the ebony frame in which the lens has since been preserved as you see it here. The lens now resides at the Museo Galileo (http://www.museogalileo.it/en/index.html) in Florence, Italy. Galileo's small telescopes were difficult to use because they produced a very narrow field of view, and the optical quality was certainly inferior to so-called "toy" telescopes made today. His tube designs were constructed from two wooden half-circle pieces that were held together with copper wire and then wrapped with paper. There were two housings on either side of the tube: one held the eyepiece, and the other held the objective. There was no finderscope, and viewing was in the straight-through style, which would have caused considerable fatigue during long observations. His mountings must have been of good quality though, because of the excellent quality of his observations of stars, planets, the moon, and the sun.
 As I reflect on Galileo's telescope, it reminds me of my own 1970-era Kmart 'Focal' brand 40mm diameter telescope with a straight-through zoom eyepiece that my mother purchased for me when I was 9 or 10 years old. That telescope planted the seeds that would inspire me to eventually start my own telescope company and to meet many amazing astronomers, astronauts, and scientists along the way. I took my Kmart telescope to the Texas Star Party this year and revisited the views through its small 40mm objective under dark skies to observe M13 and a few other deep sky objects. For a moment, I felt the same rush of excitement and wonder that I experienced so many years ago, and I had a profound moment of gratitude to my caring parents who recognized my passion for exploring the stars. I then took one of our new 70mm refractors and turned it to M51 — the Whirlpool Galaxy — and I was shocked. This galaxy is 25 million light years away! Light travels roughly 6 trillion miles or nearly 10 trillion kilometers in just one year, so you can do the math to calculate how far away the Whirlpool Galaxy is. I could not only see the main galaxy but I could see the interacting galaxy, NGC 5195. I have to say I was really impressed, and I wondered how many of my friends with their large telescopes would have also been shocked at how well this galaxy looked in this 70mm telescope. I am sure that Galileo himself would have been totally amazed.
If you are someone who loves the stars and want to experience the adventure that Galileo started more than 400 years ago, then it's time to get a small telescope and learn the night sky. To help, we have selected two models from the Explore One line and reduced the price way below their already affordable regular price:
'Theseus' 60mm AZ Telescope with Case - Reg. $79.99 - Now $49.99
'Gemini' 70mm AZ Telescope with Premium Eyepieces - Reg. $99.99 - Now $59.99
I'm sure that many of you who are experienced astronomers also got your start with a small telescope, and, in doing so, you became part of a community that continues to explore the universe with optics to gain a greater understanding of our origins. And for those of you who have never owned a telescope, there is always room for more and there has never been a better time to start what could be an exciting life of exploration. | 
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