How Newton’s Telescope Changed the World

Sir Isaac Newton is often considered as the greatestreflector telescope but it isn’t true. Credit for
Astronomer and Mathematician to ever live. There is amaking the first reflector goes to and Italian Monk,
lot of validity to this claim. This article looks at hisPhysicist, and Astronomer named Niccolo Zucchi. He
famous reflector telescope and describes some of hispublished a book on Optics in the 1650’s and it is
discoveries.this book that inspired Sir Isaac Newton to build his
A reflector telescope is one that uses a mirror ratherown telescope. Zucchi created his first reflector
than lenses to bend light and magnify images.around 1616 while Newton completed his first (and
Reflector telescopes, because they are easier tofamous) telescope in 1670.  But while Zucchi did make
make and can be made in sizes much larger thansome new discoveries with his telescope it didn’t
refractors, are an invention that changed astronomywork well and was difficult to make and to use.  It
and our understanding of the universe.  The largestwas Newton’s telescope that worked really well
refractor telescope in the world is forty inches inand that brought the art and science of reflectors into
diameter and reflector telescopes dwarf this inthe world of science.
comparison. There are currently several reflector typeThe real genius of Newton’s Telescope
scopes that are over four hundred inches in diameter.All of that stuff is remarkable but there is something
Why a reflector is better than a refractormuch more important in Newton’s Astronomy and
If you are familiar with a prism or a rainbow you canin his telescope.  He didn’t after all, discover
understand why reflectors are superior to refractors.moons around Jupiter like Galileo did, or plot the return
When light passes through glass the different bandsof a comet like Halley did. But what he did do was tie
(or colors) pass through at different angles and thisin Mathematics, Astronomy, and our understanding of
causes aberrations or problems in the images. This isthe universe using his telescope and his theory of
called chromatic aberration and it gives us distorteduniversal gravitation.  He proved mathematically that
views of what we see through a lens.  In the time ofgravitation was a two way operation and that while
Newton glass making and lens making was verythe earth pulled on a falling apple so the apple too
primitive and the problems of chromatic aberrationpulled on the earth.  This was clearly seen, calculated,
were not yet overcome. Today we can make lensesand confirmed in the motions of heavenly bodies which
that have almost no chromatic aberration but wewas refined and made possible by the new science of
can’t make them very large. When a lens gets toreflector telescopes which we can credit to Newton.
be really large it gets very heavy and its own weight Sir Isaac and his telescope carried on with the work
will distort the lens and ruin the image.of Copernicus and Galileo by furthering our
Newton’s telescope solved these problems. Aunderstanding of the universe we live in and helping us
mirror doesn’t pass light through it. It simply bouncesto realize there are laws that govern the whole of the
all the light off the surface. There is no chromaticuniverse.  And this rule holds true for falling apples and
aberration at all. And because you only need tofor planets revolving around stars.
bounce light off the surface you can place the wholeThe actual telescope that Newton built still survives
mirror on a supporting structure or base which takes atoday and is in the care of the Royal Society of
lot of the weight off the mirror. This way you can buildLondon. They keep it on display in London and
much larger mirrors without any distortion.sometimes it travels the world as part of an exhibit.
It is commonly thought that Newton invented the first