There was 2020, people have found life on Mars and have sent 4 scientists for further studying there. It were: Kim, Côme, Felix and Foliks.
The civilization living on Mars was reasonable. There were huge cities. Marsipntsa have accepted inhabitants of Earth with the world, a lot of things they were told.
The most interesting and important there was a story about how marsianets fought against garbage. They told that the garbage was real threat for Mars. And the fact that they haven't coped with her up to the end many living beings have died because of garbage. Many stations making energy were located near the cities, and because of toxic agents these cities have been completely destroyed.
And only after that marsianets have thought of the real relay of garbage. 
Also marsianets have told how they travel in space and that they were afraid of contact with inhabitants of Earth, but everything wasn't so bad, and it is even good. Kim and Felix at that time being with marsinayets, rasszat that they have problems with garbage on Earth too and they are afraid with it. After that scientists have departed back on the earth and have told about what happened to them.
After this garbage became much less and chances of longer existence has increased.