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Far beneath the ship / The world is mourning
They don't realize / He's alive
No one understands
But Major Tom sees / "Now the light commands
This is my home / I'm coming home."

Peter Schiling, Major Tom

I found myself waxing poetic after reading this question about the indicator light to tell when Apollo 8 entered the moon's sphere of influence.

When that light came on there was silence – it was a kind of dawning – we were witnessing the first time human beings were falling away from the Earth.

What goes up must come down. It's a law. This is simply how it works. Or worked. In the last century we developed enough technology to go up... and stay up. Someone who enters the moon's sphere of influence can simply choose not to initiate any burn, and wait for their final destination on the moon, never to return to earth again.

But the moon is destined to come home as well:

The Moon will be torn to pieces and every crater, mountain, valley, footprint and flag will be scattered to form a spectacular 23,000-mile-diameter (37,000-kilometer) Saturn-like ring of debris above Earth's equator. The new rings will be short-lived. Theory dictates they'll eventually rain down onto Earth's surface.

So even those who have had the opportunity to spend the rest of their days on the moon (should they have chosen as such) were destined to return, though on a much longer timescale than one might otherwise think.

Of the 533 humans who have been in orbit, have any of them been sent into space with enough propellant to actually escape Earth's grasp, should they have chosen to use the fuel in that manner? Has any human ever had the choice to never return to Earth? (or at least choice not to return with the blessings of ground control, in case there were any missions where the astronauts had the delta-V but not the authority required to use it)

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    $\begingroup$ Just a note: the Moon getting torn to pieces is not nearly as sure as it was believed not long ago. Moon is constantly accelerated by Earth's tidal forces into increasingly higher orbit, and opinions are on the fence whether it will a) enter mutual tidal lock with Earth, then gradually spin down and get torn to pieces, b) escape Earth's gravity, c) get swallowed by expanding Sun, along with Earth before either of two other options happen. $\endgroup$ – SF. Feb 26 at 8:58
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    $\begingroup$ Has any human ever been aboard a spaceship capable of leaving Earth's sphere of influence? ('leaving Earth permanently' has been a choice of everyone who's ever set foot on the moon) $\endgroup$ – Mazura Feb 27 at 0:58
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    $\begingroup$ @Mazura No. You didn't read the question. The point is that the moon (and hence everything on it) is due to fall back to earth eventually. (Although SF questions that premise). $\endgroup$ – Martin Bonner Feb 27 at 15:35
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    $\begingroup$ @MartinBonner True. There's more cut and dry phrasing of this to find humans who could have left the sphere of influence of earth and the moon. I chose this phrasing for three reasons. 1) It's more poetic. 2) It's closer to what I'm actually interested in, and 3) in phrasing this way I also opened the door up for frame challenges like SF's comment above. $\endgroup$ – Cort Ammon Feb 27 at 15:44
  • $\begingroup$ @SF - where are you getting this? We're loosing our moon at like 2.5 centimeters a year or something. How's that ever going to stop if it's outside the Roche radius? $\endgroup$ – Mazura Feb 28 at 0:23
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Of the 533 humans who have been in orbit, have any of them been sent into space with enough propellant to actually escape Earth's grasp, should they have chosen to use the fuel in that manner? Has any human ever had the choice to never return to Earth?

Apart from the Apollo missions, no crewed spacecraft has had anything like enough propellant to leave Earth orbit.

Apollo is a very different story. After translunar injection, the Apollo CSM/LM stack could produce an additional 3600 m/s of delta-V by expending first the lunar module stages and then burning all the service module fuel. This is enough to reach Venus, Mars, the asteroid belt, or even Jupiter. However, the ship would only have crew life support for a couple of weeks at most -- not enough to reach any interesting destination alive.

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    $\begingroup$ I think you'd get more delta-V by first firing the CSM, then descent, then ascent module. (might get even more if one could use the descent module without the ascent module but I think that would be impossible. Also, firing all these in LEO would result in massive Oberth benefits. Still, obviously there was not nearly enough life support capacity to get anywhere far. $\endgroup$ – SF. Feb 26 at 9:19
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    $\begingroup$ @Mehdi Hang on, they're in the notoriously unforgiving environment of space, sat on top of tonnes of explosives, supplied with breathable air by a sometimes-temperamental filter, kept at a survivable temperature by a sometimes-temperamental AC system - and you're looking to give them yet another way to die quickly? What's wrong with any one of the myriad of things which they need to actively stop from killing them? $\endgroup$ – Graham Feb 26 at 17:24
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    $\begingroup$ @Mehdi Jim Lovell is on record as saying that if the crew wanted to commit suicide, they'd simply vent the cabin to space. They'd lose consciousness with little discomfort in seconds and die shortly thereafter. See this QA for more on the topic. $\endgroup$ – Russell Borogove Feb 26 at 18:19
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    $\begingroup$ @Mehdi: No. The astronauts said later the way to commit suicide was to open the cabin re-pressurization valve (it's supposed to be used while floating in the ocean). $\endgroup$ – Joshua Feb 26 at 19:45
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    $\begingroup$ It's worth noticing that the delta v to reach the moon is almost the same as the delta v required to escape earth, and to actually get in an orbit around the moon you'd need more than for escaping earth. $\endgroup$ – paul23 Feb 26 at 21:54
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Soyuz 11

The crew did not return to Earth in their lifetimes. This interpretation is obviously not what you are talking about though. Instead what is of interest is human's remains that do not return to Earth ever. In this case there is also a definitive answer.

Clyde Tombaugh

Tombaugh died on January 17, 1997, when he was in Las Cruces, New Mexico, at the age of 90. He was cremated. A small portion of his ashes was placed aboard the New Horizons spacecraft.

You may consider this cheating since it was only a small portion of his remains, but more than just a hypothetical, it actually happened, and not only did this portion of his remains escape the grasp of Earth, but also the grasp of the sun.

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    $\begingroup$ Neither of those are the kind of thing I'm looking at, but I applaud the clever reinterpretations, especially Clyde Tombaugh! I had not even considered the case where the decision to leave the Earth's grasp was made on the ground, rather than mid-flight (and posthumously, no less!). That's definitely in the spirit of what I was after, even if there's some definite technicalities involved! $\endgroup$ – Cort Ammon Feb 26 at 3:09
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    $\begingroup$ @CortAmmon see also Gene Roddenberry $\endgroup$ – mcalex Feb 26 at 3:31
  • $\begingroup$ For Soyuz 11, they died at 168 kilometres altitude, so they did not escape Earth's grasp and their bodies fell back to Earth. $\endgroup$ – Cœur Feb 27 at 3:49
  • $\begingroup$ @Cœur hence why I said they did not return to Earth "in their lifetimes." I mainly brought it up to highlight the point that the question really pertains to human remains and not living humans, before giving the answer as it pertains to human remains. $\endgroup$ – Lex Feb 27 at 4:53
  • $\begingroup$ Dead people don't have choices, if you're going to start the pedantry. $\endgroup$ – jpmc26 Feb 27 at 16:31
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No and yes.

Rockets are costly things and no human ever left Low Earth Orbit, except the Apollo astronauts. Others had not enough fuel to do that.

The Apollo astronauts had theoretically the option to contradict their mission requirements and choose death

  • on the Moon
  • on Moon orbit
  • or somewhere between the Moon and Earth

by commiting a suicidal sabotage. They didn't do it on obvious reasons.

One of the worst known violation of their rules was as John Young astronaut has taken a sandwitch with him into the space.

The escape speed from the Earth from Lunar orbit is already very small, it is possible, that the few fuel of the Apollo - reserved for orbital correction - could have been enough to visit the interplanetary space - without any way to ever return.

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  • $\begingroup$ "without any way to ever return" - you'd still be on an Earth-intersecting orbit. You could just sit and wait. Might get home, might smash into the Moon, might get swept by a lone asteroid. It will take a lone time and the probability is low, but you might still get back to Earth by accident eventually. $\endgroup$ – John Dvorak Feb 25 at 17:46
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    $\begingroup$ @JohnDvorak Yes, it would be intersecting and probably not very far from the orbit of the Earth, however a next hit of the Earth - after a year - would be still very improbable. The probable result would be a near-Earth travel after $\approx$ a year, and then a Tesla Roadster-like chaotical orbit. It is nearly sure, that the ship would not enough fuel to hit Earth, even if it would be still working (probably it wouldn't, the whole Apollo travel was planned for a week, not for a year). $\endgroup$ – user259412 Feb 25 at 17:50
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    $\begingroup$ "not in orbit" Around what? $\endgroup$ – Organic Marble Feb 25 at 19:01
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    $\begingroup$ @NuclearWang Apollo may have had enough fuel to leave Earth's orbit, but you need way more fuel to leave the solar system. I've checked. $\endgroup$ – John Dvorak Feb 25 at 19:23
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    $\begingroup$ @JohnDvorak Escape velocity from the Solar System is around 42km/s from the orbit of the Earth. The Earth is already moving with 29.8 km/s, so around 12.2km/s delta V would be enough to an escape from the Solar System. Now the problem is that typical satellites, probes have around some hundreds m/s delta V reserve after they've left the gravitational well of the Earth. $\endgroup$ – user259412 Feb 25 at 19:50

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