Okay, galaxies near the edge of visible space can approach the speed of light. Right? Now lets take a galaxy which is located at, let's say 12 billion light years distance and red shift is calculating the galaxy is moving away from us at 250,000km/s. That's okay, we still can see it, but it's quiet red in color.
But now comes the interesting part. Whoever is ON that galaxy and is watching OUR galaxy, they come to conclusion that, if the distance is the same, and the distance IS the same, OUR galaxy is also receding at 250,000km/s. Sounds reasonable right? Everything in the universe is moving away from each other.
Now if that galaxy and our galaxy both move at 250,000km/s they move away from each other with 500,000km/s in relation to each other. That's faster than the speed of light.
HOW CAN IT BE THAT WE STILL CAN SEE THAT GALAXY?
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