The growing problem of space junk poses a risk to future space missions, but the solution isn't going to be easy.
Who's going to fix the space junk problem? : Read more
Who's going to fix the space junk problem? : Read more
If nobody cares, the answer is very simple. Accidents with manned or unmanned vessels will occur. These may result in deaths. There will come a point where sane 'astronauts' will change their occupations. Space exploration will either cease or continue to get more difficult/dangerous. This situation will continue until either space exploration is discontinued, or some effort is made to clear the mess.
Of course, there may well be influences meanwhile from another mass - suicidal overpopulation. Even now we are destroying rain forests which contain the plants operating photosynthesis which produces the oxygen we breathe. Less plant life, less oxygen - and more organisms to breathe what there is. And this is only one facet.
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