Did you know, that galaxies are not really all those vibrant colours?
Galaxies are mostly invisible to the human eye... NASA just assigns colours to the different wavelengths emitted so they can visualise it's characteristics.
It depends on the individual telescope whether or not those are true color images, though it is true that they're not actually vibrant colors like seen in images because they use incredibly long exposure times to collect the images from light that's basically just trickling in. This is commonly referred to as the "light bucket" method. This way you can get very distinct and clear images of incredibly faint objects like nebulae and galaxies.
@BoobooSnafu Indeed, it is pretty damn fascinating stuff. It's the principle behind modern digital cameras, which we have the space program to thank for. CMOS light sensors were developed in response to figuring out how to get pictures of the stars and planets back from probes. Whether the light spectrum being captured is in the visible wavelength or not varies.
@SW-User it's time consuming, but creating a full visual image that they can interpret is really useful - it's like - 'a picture paints a thousand words.'
