this post was submitted on 08 Jul 2024
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Or on an airplane
Maybe we can amend the definition of "on Earth" to "inside the atmosphere" for purpose of that tweet
No! We most dive deeper into Achually Land!
How far does "the atmosphere" go? Because technically the ISS is in the thermosphere, which is part of Earth's atmosphene.
Already, let's go with the karman line like everyone usually does.
I'd go with the mesosphere, because that's where meteors burn up. That's a little below the karman line and is defined by actual qualities, instead of an arbitrary number. Regardless, both exclude the ISS. :)
Are you an astrophysicist?
No, just your garden variety nerd.
I would go with what the professionals use.
But "the professionals" don't agree. Most notably, the US Air Force says you're an astronaut if you go above 80km (approx the start of the thermosphere), and NASA switched to that standard too. At 80-90km, you can sustain an elliptic orbit, and around 150km, you can sustain a circular orbit.
The 100km Karman line doesn't signify anything, it's just a nice multiple of 10 that's pretty close to more important points. It's not based on science, the original science by Karman was the highest theoretical height for an airplane, which was just over 80km, it's just a nice number close to actual science.
So no, I'm not just going to accept 100km "because science."
Ok
No human has ever been not gravitationally bound to the earth. So really this type of showerthought seems to be too early. If we send astronauts to Mars, it will be easier to say they have been separated from Earth.
I like this.
It's really the only non arbitrary answer.
Yeah, that's probably a better metric.
Would you count a permanent base on the moon? I think it should, since you'd be more impacted by the moon's gravity than Earth's, despite still being in Earth's orbit.
The moon and everything on it is gravitationally bound to the earth. So I would not count a moon base as having escaped the Earth.
So, is the next set of goalposts that we need to except the solar system?
Planes are supported by the gas that is part of Earth, it's not a lot different to boats that are supported by Earth's water