I am writing a science-fiction book, and my alien visitors come from a star "seven light years away". Can anyone let me know how many stars are at that distance, and whether we know if any of those stars could have Earth-like planets around them? Thanks in advance!
It doesn't - there is a small wobble called libration.
But generally yes, we always see the same side, and this is due to tidal locking. Over time, as a satellite orbits a planet, the tides caused on each other by their gravity cause them to slow down in spin, like brake shoes on a wheel cause it to slow...
Most of them (14) are near Uranus' equator, within 4.3 degrees. The nine outermost of them have inclinations ranging from 51 degrees to 167 degrees ( = -13 degrees).
Assuming that actual aliens were involved, I doubt that anyone knows where they would have come from. I doubt that they were real, but, if they were, the politicians either don't know or aren't telling us.
Yes, anything that spins has equator and poles. And black holes do spin.
Yes, the Universe includes all of space and time, past, present and future. That is why it is called the space - time continuum
and seti doesn't detect their radio transmissions because they're too dumb to invent radio? are we the smartest civilization in the galaxy?
Is it reminisce of when planet theia hit new born earth??
Or do you think it will be multiple countries working together? Or maybe even a private company like SpaceX or Blue Origins?
I just hope it's in my lifetime. I really want to witness the start of the space age. I feel like I was born either 50 years too early or 50 years too late. Seems like we're at an...
Finite and mathematiclly "flat" and expanding.