A while ago, I accidentally created a world where the mountains were so tall that you can’t add any more blocks. It was way above the cloud layer…
Try as you might, you can’t place any blocks on this plateau — it gives you an error message. But, in Creative Mode, you can still fly above this! So I gave it a try. I flew so high that I lost all sight of the ground. At this point even though it was night, the sun re-appeared (was I seeing around the planet???)
Using the F3 key, I displayed the X, Y and Z coordinates. Y is the altitude. It seemed to take forever, but I finally got above 1000 meters. I kept expecting something terrible to happen (would it crash my computer?) so I got scared and gave up.
So — how high up can you fly in Creative Mode? Using our handy-dandy Google, I found this video
The short answer is, you can go 1 quadrillion meters. One quadrillion and one, and you get an error message. I’m not positive but I think the error is so severe that you can never enter that world again! The guy in the video used the “teleport” command, which I don’t have, so I’m not going to try it.
One quadrillion can also be written in exponential notation as 10 to the 15th power.
Just for scale, one AU (astronomical unit) is a measly 1.5 times 10 to the 12th power. (One AU is approximately the distance from the Earth to the Sun.) So in Minecraft, you can fly about a thousand times the distance from the Earth to the Sun. This is waaaaaay past Pluto, which is an average of 40 AU away.
A lightyear is 9.5 times 10 to the 15th power. That means the Minecraft sky extends about A TENTH OF A LIGHTYEAR away from the world’s surface.
Won’t be able to reach any stars. According to this article, the closest star to our sun is Proxima Centauri, at 4.5 lightyears away.
Of course, in the Minecraft world, there could be stars much closer than that, who knows?