The Evolution Of The Telescope

Telescopes are incredibly useful devices that allow us to see things that are far away from us.

Humans have been using telescopes for hundreds of years, for many purposes.

Over the centuries, telescopes have evolved dramatically, both in terms of their designs and their purpose.

The Evolution Of The Telescope

Since their invention, telescopes have changed from simple handheld devices that allow you to see into the distance, to massive technological marvels that can photograph objects billions of light-years away.

But how exactly have telescopes evolved since their invention?

And how have these tools been modified and improved to let us see the far reaches of space?

Don’t worry, because this article has the answers to all of these questions (and more)!

Here we’ll take a look back at the evolution of the telescope, from its invention to more modern uses, and even how massive astronomical telescopes are being used to photograph stellar bodies that have never been observed before.

Ready? Then let’s get started!

What Is A Telescope?

First things first – we need to cover the basics.

If you aren’t familiar with telescopes or never really wondered how they work, it can be tricky to understand the ins and outs of telescopes.

Traditionally, telescopes were cylindrical hand-held devices that could be used to view objects a large distance away.

They did this through the use of mirrors; the inside of a telescope contains several small, curved mirrors that reflect and magnify an image.

Early telescopes didn’t use mirrors, and instead used curved pieces of glass called lenses to focus on a distant image.

While telescopes that use mirrors are the most common, there are still telescopes that use glass lenses instead – these are known as reflecting telescopes and refractive telescopes, respectively.

Most modern telescopes still use mirrors, but these can now be perfectly engineered and treated to make them extra-reflective and have a better focus.

This allows them to zoom farther while maintaining a high-quality image, free from blurring or distortion.

Early Telescopes

Early Telescopes

The first telescope ever recorded was made in 1608CE, by the Dutch spectacle-maker Hans Lipperhey.

This telescope was fairly primitive, consisting of a tube with several concave and convex glass lenses inside, that could magnify an image by 3-4 times its size.

Despite being relatively unimpressive by today’s standards, early telescopes were sensational due to the possible functions they could offer.

Many people mistakenly believe that the Italian astronomer Galileo Galilei was the inventor of the telescope; while he may not have been the first person to make a telescope, Galileo was the first person to point it towards the stars.

After learning about Lipperhey’s device “for seeing things far away as if they were nearby” (as Lipperhey described it in his patent), Galileo created his own improved version of the telescope that he used to observe the planets and stars in the solar system.

How Telescopes Have Changed Over Time

Since their invention in the early 17th century, telescopes have changed in a variety of ways, from their design and functions to their purposes.

Over the next century, various astronomers and physicists improved and refined Lipperhey’s and Galileo’s designs to create a far better instrument without the limits of its earlier iterations.

Isaac Newton developed the first reflecting telescope in 1668.

By including a small, flat mirror in the telescope, Newton was able to reflect the light coming into the telescope.

This reduced the amount of refraction caused by glass lenses, which cleared up the image and helped reduce color distortion created by refraction.

Newton’s telescope (also known as the Herschel Reflecting Telescope) allowed users to get a much clearer, color-corrected image with a further zoom.

Later that century, in 1672, Laurent Cassegrain added a second, convex mirror to his telescope design.

This further enhanced the image in the telescope, improving its quality and distance.

Color was one of the biggest challenges with telescopes, as the refracted and reflected images observed through the telescope suffered from distorted altered colors.

This issue persisted into the 18th century, until Chester Moore Hall developed an achromatic lens for his telescope.

When light travels through a regular ‘chromatic’ lens, it is fractured into its constituent colors – this is what caused the color distortion in other telescopes at the time.

By using an achromatic lens (which doesn’t separate the colors in light), Hall’s telescope was able to avoid these issues and produce a color-corrected image.

Later, more modern telescopes also started to feature other alterations to their lenses and mirrors to help produce a clearer, more accurate image.

In the 19th century, Leon Foucault silvered the mirrors within his telescopes.

This is a process that involves coating glass and mirrors with a silvery coating that massively increases their reflective properties.

With this method, Foucault further improved the distance seen with a telescope, and was able to produce far clearer images.

Foucault’s ‘silvering’ method was further improved upon in the 1930s with the introduction of ‘aluminized’ lenses, which (in addition to their highly-reflective properties) maintain their coating for much longer.

These massive strides in the technologies used for telescopes have led to some incredible discoveries by astronomical researchers.

Using these telescopes, astronomers have managed to observe and record many astral bodies, from the planets in our solar system to distant galaxies far beyond our own.

Telescopes Today

Telescopes Today

In modern times, telescopes have been pushed far beyond the limits of what they could achieve in the early 1600s.

Modern telescopes have a much farther range of sight than they once did, and even simple astronomical telescopes that can be used at home are capable of seeing far into the night sky.

Despite their increased functionality and improved quality, most modern telescopes aren’t too dissimilar from the original design.

The glass lenses have been swapped out for specially-engineered mirrors, and many modern astronomical telescopes have switched from their hand-held origins to a more stable mounted design, that stays steady and secure while supporting the telescope’s weight to give you a clearer picture.

Additionally, these types of telescope typically have an eyepiece on their side with a mirror reflecting incoming light towards it; this reduces glare and offers a more focused image.

Even personal terrestrial telescopes are capable of capturing clear images of space, including planets, galaxies, and constellations.

Some telescopes take the simple tool to the extreme, and have been used to capture images of the far reaches of space.

One of the most notable of these large astronomical telescopes is the Hubble Space Telescope.

This is a massive telescope used by NASA to photograph distant celestial bodies and observe the furthest parts of our solar system.

The Hubble Space Telescope is huge – it’s around the size of a school bus, and weighs almost 25,000 pounds.

Its massive size and incredible technologies allow it to observe incredibly far away objects, and because it orbits outside the Earth’s atmosphere, it doesn’t have to deal with the distortion and debris that plagues most telescopes.

Massive astronomical telescopes (like the Hubble Space Telescope) have been key in examining the depths of our solar system, and have allowed us to observe parts of space that have never been seen before.

These include the Hubble Space Telescope discovering previously-unknown moons orbiting Pluto, and the Event Horizon Telescope capturing the first-ever image of a black hole.

Final Thoughts

The telescope has changed dramatically since Hans Lipperhey first created his telescope in 1608.

Since then, the design and functions of telescopes have been improved countless times, evolving from a simple tool that magnified an image by 3-4 times, into a technological marvel that can capture clear images of planets billions of miles away from Earth.

Telescopes have had a massive impact on astronomy, and have helped to shape our understanding of the universe and the vast space that exists beyond our atmosphere.

They’ve also played a major role in helping humanity explore space, and understand the mysteries of the cosmos.

It’s unclear where telescopes will take us in the future, and what fascinating discoveries will be made using these incredible devices.

Until then, all we can do is wait and see!

Gordon Watts