I know we get them through massive telescopes…. But how do they capture images so far away? How do they work?
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Some of what you see is long exposure photography, where the camera is attached to a telescope that moves with the rotation of the Earth. Some photography you see of distant galaxies, etc are not photographs, or are only infrared and the astronomers add false color later.
So you can search this sub for “how do cameras work” for more detail, but you need the TL;DR: that photography is literally “capturing light”. And the more massive your… light capture device, the more light you’re going to capture. So being a “massive telescope” _really_ helps.
You know how you see [long exposure](https://www.google.com/search?q=long+exposure) images? That’s a camera keeping the shutter open and absorbing more light as it streaks by.
These massive telescopes can keep the “shutter” open for ages, and can move around so they’re pointing at the same patch of sky. That way get sharp images rather than streaks.
There’s also no atmosphere in space to distort things.
Finally, a _lot_ of post-processing happens after images are taken.
**EDIT** to add that for planets in the solar system, we actually send spaceships over to take up-close pictures.
Don’t overestimate how detailed they are. They’re showing a lot of features, but those features are very, very large.
When you see swirls in the atmosphere of Jupiter, like on this page:
https://solarsystem.nasa.gov/planets/jupiter/in-depth/
Be sure to look at the size comparison: those details you’re looking at are the size of Earth. Something as small as, say, Alaska, you probably wouldn’t be able to see, because the pictures aren’t that detailed.
>I know we get them through massive telescopes…. But how do they capture images so far away? How do they work?
Actually, quite a lot of them are from very light telescopes – ones attached to interplanetary probes sent to explore the planets. Quite often these images are mosaics, stitched together from multiple pictures.
Most of the super-sharp super-detailed photos you see of planets were not taken from telescopes on Earth. They were taken by relatively normal cameras attached to interplanetary space probes that we launched from Earth and flew close to that planet.
Even the best planet photos from the biggest Earth-based telescopes (and even space telescopes that orbit near Earth) look terrible compared to the images sent back from space probes like Voyager, Cassini-Huygens, etc. The further the planet, the worse images we can get from Earth. Objects like Pluto show up as pixellated blobs on even the most advanced telescopes.
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