Witness for Tomorrow

In the distant constellation Centauri, there is a gaseous and pleasant planet DR911. However, due to their over-exploitation of resources, their planet gradually died. It happened that they received information from the earth at that time, so they came to the earth through the wormhole and launched an invasion. However, because the earth at that time had been supported by alien technology, they also aimed at the past... In what direction will all this develop?