How can we see so far away with telescopes?


How can we see so far away with telescopes?

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It takes really faint light from a bunch of directions and bends the light through a curved lens into a single point that you look at

Telescopes collect light from a large area and then condense it into the small eye-piece. The way it gets light from a large area is usually by having a large lens or mirror. All the light that falls on it gets collected and sent to the eye-piece. This way we get far more light from a far-away object than would otherwise get through our rather small pupils, making that object visible.

In the other hand, the furthest object that can be seen with a naked eye is the Andromeda galaxy which is three million light years away, so we can see pretty far away without a telescope as well.

actually we dont. this light from stars far away we can see is travelling to earth anyway. but because of the fact that there are so many lightparticles, your eyes cannot differentiate enough to see them because there are so many other lightparticles from other sources. imagine you have 10 see trough pictures and one of them is only a dot. if you place those over each other, you will not see the single dot.

now telescopes are like magnifying glasses. but they dont only make things bigger, they also minimize the amount of lightparticles from other sources.

Because there’s nothing in the way.

The thing that stops us seeing really far away on Earth is that there’s stuff in the way. Even when there’s no objects in the way, the atmosphere scatters light enough that you can’t see things well if they’re far away.

But if you’re looking up, the atmosphere isn’t that thick, so there’s nothing preventing you from seeing things thousands of light years away. Light can travel infinitely far if there’s nothing in the way.

With space telescopes it’s even easier because you don’t even have to worry about the atmosphere.