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Earth's 'Bigger, Older Cousin' Maybe Doesn't Even Exist (npr.org)
Ever since astronomers started to detect planets beyond our solar system, they've been trying to find another world just like Earth. And few years ago, they announced that they'd found a planet that was the closest match yet -- Kepler-452b. Trouble is, some astronomers now say it's not possible to know for sure that this planet actually exists. From a report: "There's new information that we can now quantify which tells us something that we didn't know before," says Fergal Mullally, who used to be an astronomer on the science team for NASA's Kepler Space Telescope. In 2015, NASA declared that Kepler-452b was the first near-Earth-sized planet orbiting in the "habitable" zone around a star very similar to our sun. The space agency called it Earth's "bigger, older cousin," and scientists were so enthusiastic that one began quoting poetry at a news conference. The original science wasn't shoddy, Mullally says. It's just that, since then, researchers have learned more about the telescope's imperfections.
Well the universe is infinite or so they say but how the fuck do they know
Actually science indicates the universe is not infinite, but is finite in both time and direction.
How do we know? Look up at the sky during the night. See how it isn't blinding you with its brightness? That is how we know.
If the universe was infinite in space, every possible point you could look at in the sky would intersect a star shining light at us.
If the universe was infinite in time, the light from all of those stars would have had infinite time to reach us, and would have by now.
If the universe was infinite in time and space, the night sky couldn't possibly be dark, it would be blinding, and would be all of the time.
You wouldn't even be able to see the fact our Sun is there, as it would be equally bright as any other point in the sky.
This is observationally not true. Thus, the universe can't be infinite in time.
So why can't the universe be infinite in just space/direction and finite in time?
To be finite in time means the universe had a starting time and will have an ending time.
We observe other stars moving away from us in all directions as time moves forward.
This logically can only mean as you go back in time those stars were closer.
The only way the universe can both be infinite in size and also have a starting time, would be for the universe to have simply appeared existing as it is at that start time.
This means the universe wouldn't be changing, it wouldn't have objects in it moving all away from us (or all towards us either for that matter)
Light travels at a fixed speed, and requires time to do that traveling. The fact light from a source can reach us today where it wasn't reaching us before is more evidence the universe isn't infinite in time.
The fact we can also see light from very distant objects from us today that are moving away from us, and then "disappear" as the object moves to a point that the light coming from it hasn't (and likely never will) have time to reach us, is evidence the universe isn't infinite in space either.
It can't be infinite in both time and space, and it can't be infinite in time but finite in space, and it can't be finite in time and infinite in space.
Process of elimination leaves the one option left: It can only be both finite in time and finite in space.
So that's how they know. An infinite universe couldn't possibly in any way look anything resembling how our universe actually looks.