Why will these aliens not send any ships to the Milky Way Galaxy?
Alien astronomers in another galaxy observe the Milky Way. By its redshift, they calculate its distance as 7.94 billion light years. Someone proposes that intergalactic colony ships be sent to the Milky Way to seed it with their kind. But the experts refuse, saying that there's no point to it.
What is the expert aliens' reason?
- vorenhutzLv 73 years agoFavorite Answer
Possibly because the expansion of the universe means that not even light can travel that distance. Wild guess, I haven't done the calculation.
- 3 years ago
vorenhutz is right.
When you look at a distant galaxy, you see it where it was when the light you're seeing left it. During the time when the light was enroute to Earth, the galaxy moved.
For galaxies one billion light years away, the increase in distance is only about 7% more than the distance you observed. The one billion light year distance increased to 1.074 billion light years while the light was traveling.
For galaxies five billion light years away, the increase in distance is about 43% more than the distance you observed. The five billion light year distance increased to 7.15 billion light years while the light was traveling.
It turns out that galaxies observed to be 7.94 billion light years away have since traveled all the way to the cosmological horizon, 13.9 billion light years away, and are now moving away from us at the speed of light. So there's no chance to close the distance anymore.
- spot aLv 73 years ago
They are already in the Milky Way galaxy
- Anonymous3 years ago
We're watching you.
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- ioerrLv 73 years ago
because it would obviously be outrageously expensive, and just as obviously there is no way such a venture would ever return any profit whatsoever to those that financed it, not in a million years, literally.