re: The size of the observable universe is 93 billion light years in diameter

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Supposedly the universe is just Uber 14 billion years old. This, the furtherest object from us should be roughly 14 billion light years away. If we observing out to 93 billion years then either the universe is a lot older than we thought or something else is going on.

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Well for one you are referring to the radius and not the diameter.

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Supposedly the universe is just Uber 14 billion years old. This, the furtherest object from us should be roughly 14 billion light years away. If we observing out to 93 billion years then either the universe is a lot older than we thought or something else is going on.

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It’s explained by general relativity. Basically, the fabric of the universe itself can expand faster than the speed of light. But an individual photon can only traverse that fabric at the speed of light. It involves some wonky space-time shite but that’s why Albert Einstein was a genius, I guess.

Can't sing about it if you’ve never seen it.

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its not like these facts can be disproven. we don't even know what or who the frick is flying around in our own atmosphere.

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How does the age of the Earth compare to the age of the observable universe? It's funny to me that we think our planet has evolved slower than life on other planets.

It took 4 BILLION years for life on Earth to put something on their moon... How does that compare to other planets?

How are we the only ones emitting radio into the universe? Even if those planets are more advanced, we should have heard their primitive emissions into space by now

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How are we the only ones emitting radio into the universe?

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How do you know we are the only planet doing this?

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How does the age of the Earth compare to the age of the observable universe? It's funny to me that we think our planet has evolved slower than life on other planets.

It took 4 BILLION years for life on Earth to put something on their moon... How does that compare to other planets?

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Scientists think the universe is about 14 billion years old. The oldest known planets are thought to be about 13 billion years old, which makes sense - Earth is thought to have formed less than 100 million years after the Sun. So planets around the oldest stars probably would have formed within a billion years or so after the Big Bang.

In other words, there are likely other habitable planets 8-9 billion years older than Earth.

Also keep in mind that, while it did take 4.5 billion years for life on Earth to travel into space, the Cambrian explosion was less than 600 million years ago. The first time pre-humans are thought to have used fire is ~1 million years ago. The first use of agriculture was ~12k years ago.

The earliest planets would have existed for 2.5x as long as Earth by now, if their stars didn’t explode before then. If life formed on these planets at the same speed as on Earth, it would have existed for 9 billion years (2.25x as long as Earth) by now. If civilizations rose at the same speed as on Earth, they would have existed for roughly 900,000x as long as all of written human history by now.

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How are we the only ones emitting radio into the universe? Even if those planets are more advanced, we should have heard their primitive emissions into space by now

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This is not necessarily true. Imagine if we put all of our resources into broadcasting radio transmissions outward, then compare that output level to the energy output of a star. Then imagine how many stars are likely between you and the nearest listener.

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How is that possible? Isn’t the universe < 14 billion years old? Wouldn’t observable universe only be able to expand < 14 billion light years in any one direction?

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Nothing can travel faster than the speed of light, but space can expand faster than the speed of light. So eventually every galaxy will be moving away from us faster than the speed of light and the sky will be only stars in our own galaxy.

And therefore, there is a line outside of which we could never reach in any way even if we traveled light speed for eternity.

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I love that we think we know this when we've been observing only a few hundred light years of distance at most.

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This is not true. We can see the first galaxies to ever exist, as they were forming, 13 billion years ago.

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Milky Way is like 80,000 light years across (I think) and we have been broadcasting radio waves for about 100 years so really hasn't reached that many starts as of yet.

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About 100,000 light years across. Within 15 light years of us there are only about 50 stars (400 hundred billion in our galaxy alone). We've been transmitting for about 60 years. So think about the fraction of stars we've hit. And then any response would take just as long to come back.

Also crazy that there are hundreds of billions of galaxies and the next closest one to us is 2.4 MILLION light years away.

(And oh btw it's gonna devour the milky way in the future)