Part 1 – Time travel
When people imagine time travel, they often don’t realize that they are also talking about space travel as well.
How Fast Is the Earth Rotating on Its Axis?
The Earth rotates on its axis once each day. Because the circumference of the Earth at the equator is 24,901.55 miles, a spot on the equator rotates at approximately 1,037.5646 miles per hour (1,037.5646 times 24 equals 24,901.55), or 1,669.8 km/h.
At the North Pole (90 degrees north) and South Pole (90 degrees south), the speed is effectively zero because that spot rotates once in 24 hours, at a very, very slow speed. (Source)
In addition to this rotation, the earth is hurling around the sun at 30km (19 miles) per second! And, our sun isn’t stationary in the galaxy, it travels 792,000 km (483,000 miles) per hour (and still takes 230 million years to complete a rotation).
These numbers are mind boggling. Now, going back to the idea of a time machine, if I was able to go back in time to only 5 years ago, the earth that existed back then was millions of kilometres away from where the earth is now. I’d have to travel through time and space.
Part 2 – The light of the stars
When we look at the stars, we only see their history. The closest star, our sun, is not where we see it, it is where the sun was 8 minutes ago, because that’s how long it took the light to reach us. For stars that are light years away, they could already have gone super nova, and wiped out their solar system, and generations later our ancestors will still see that star, not knowing it no longer exists. We are literally looking back in time when we look out into space.
Part 3 – the edge of the universe
A concept I can’t wrap my head around is what’s beyond the edge of the universe? And if you have an answer for me, what’s beyond that? This to me is the definition of infinite… the idea that no matter how far away something is, there has to be something still farther away.
If you had a string that was infinitely long and you cut it in half, you’d have two strings that are infinitely long. Think about that for a while… then try to forget it. 😜
Why should we believe that our universe is the only universe? Could there be multiple universes in the empty void beyond our own? Could our entire universe be an atom in a massive other universe? What secrets do the edge of our universe hold? We will never know because it takes too much time for the light way out there to reach us.
—
These are 3 ideas about space and time that peak my curiosity and make me marvel at life, the universe, and everything… while we hurl through space on an insignificant rock around an insignificant sun, in an insignificant galaxy… thinking thoughts that significantly challenge my intellectual understanding.
