Alita was abandoned: In fact, in the 200 years since Alita was awakened by Dr. Eide, human beings have successfully colonized the solar system under the guidance of computers. Of course, colonies are not always controlled by the earth, but gradually separated from the control of the earth, gradually forming independent political, cultural and economic systems of each colony, and different colonies are constantly competing for resources. Because a war broke out between Jupiter and Venus in the universe, which affected the stability of planets of the solar system as a whole and gradually evolved into a war of cosmic galaxies. Venus is constantly using technical means to transform the human body, and Jupiter is constantly urging Mars to send mecha to slaughter the planets.
Here, Alita, as a soldier excluded from Mars, was sent to perform a very serious task, that is, to destroy the quantum computer in Earth orbit. Of course, the task was completed quickly, but it also caused terrible consequences. A large number of colonies went bankrupt and 450,000 people died. Alita was captured by the agent "Blue Widow" when she was evacuated. Alita's brain and heart were hypnotized for more than 200 years because of injuries, so she was abandoned to the scrap iron city.
Of course, the capture of Alita made the mecha of Jupiter and Mars draw a clear line immediately, and because the mecha sent by Mars destroyed the quantum computer, people from other planets quickly joined forces to destroy the mecha, and the mecha technology stagnated from then on.