I don’t know about you, but without my glasses, I literally cannot see anything, even if it’s right in front me. Whether I’m sitting in the classroom trying to take notes from the professor’s lecture or trying to watch my favorite Netflix show, my ability to actually see anything with my naked eye is severely impaired. Now, when I’m able to actually use my glasses, I can actually see things. It doesn’t matter whether it’s the board in class or the TV screen — using the lenses to bend the light around my eyes, my glasses are able to change the light rays entering my eye in such a way that allows me better sight than I would have without them.What’s crazy is how the concepts used to create glasses can be applied on a much larger scale to allow us to view objects much further away than a TV screen or a whiteboard.
Telescopes, or optical devices that magnify distant objects through the use of particularly-arranged curved lenses and mirrors, allow astronomers to peer through Space and observe all that it has to offer. More specifically, telescopes can be typified by their two most fundamental characteristics — light-collecting area (how much light the telescope can collect at a given time) and angular resolution (the smallest angle we can differentiate two distinct dots. Additionally, the different types of lenses and mirrors used in specifically different arrangements allow experts to create fundamentally different types of telescopes. From the textbook, we know about both refracting telescopes (glass lens collects and focuses light) and reflecting telescopes (precisely curved mirror gathering light, secondary mirror reflects the collected light). A graphic demonstrating how they actually work in shown below.
And, it gets even more interesting when we throw the telescopes into space (Earth’s orbit) — this allows the telescope to avoid electromagnetic radiation, it reduces other atmospheric influences / side effects, and it mitigates light pollution from around Earth. Even though they’re more expensive and difficult to maintain, space telescopes allow astronomers to see beyond our Solar System into the Observable Universe.
It would be remiss not to mention the most known and relevant telescope to this article post — the Hubble Space Telescope. The first major optical telescope put into space, Hubble represents one of the biggest pieces of innovatory machinery in modern astronomy. Not only has it made more than 1.3 million observations since it was deployed to Earth’s orbit — it generates roughly 10 terabytes of Science-related data per year, it is the length of a full school bus, and it is stupidly powerful and accurate (according to NASA, it can see in a way akin to “seeing a pair of fireflies in Tokyo that are less than 10 feet apart from Washington, DC”). And, as a reflecting telescope, it uses mirrors larger and heavier than any human being that ever existed.
A picture of the Hubble Space Telescope can be seen above. At the end of the day, it really is just mirrors, solar panels, communications hardware, and lots of very finely tuned pieces of metal!