I saw a post on reddit saying NASA has a telescope that is able to see the creation of planets and stars from 13 billion years ago. How can that work?
Link to post: https://www.reddit.com/r/interestingasfuck/comments/ke2p2r/nasa_is_about_to_launch_a_telescope_that_can/?utm_medium=android_app&utm_source=share
In: Physics
Imagine you have a camera in one room that’s recording someone dancing. The feed from that camera is being displayed live in another room on a TV that you’re watching. Logically, you’d assume that person must be in the room dancing right now because that’s what you see on the TV right now.
Now imagine that instead of the signal going from the camera to the TV over a relatively short cable that’s a few meters long, it instead has to go through a cable that’s billions of meters long. It’s going to take a little bit of time for the signal to make it from the camera to the TV. The result is what you’re seeing on the TV actually happened a few seconds ago but you’re only just now seeing it.
That’s what’s happening when you observe distant things in space. Light travels very fast, but not instantaneously. So with enough distance, you start to get a delay between when something happens and when you can see it happening.
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