Is it possible to make a man-made world?

Answer 1

AnswerMan has already made an artificial satellite. With enough effort and expenditure, we could make one large enough to support a range of lifeforms, including vegetation, so as to make it self-sustaining. If such a project qualifies as a man-made world, then the answer is 'yes'. But such a world would always be artificial, unlike the planets and moons that are the real worlds. We could not really create a man-made world like Earth or Mars. So if a man-made world has to be like the planet Earth, then the answer is 'no'.