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The Junkers are mentioned on one page in the bonus content that was added to WWR Complete. This story gives us the most direct insight on the Martian situation in published form. "Junkers" is the title given to the people who were left behind when the Martians migrated and left Earth. The Junkers are described as following the same idea-sets as Martians, but being "limited in number" and "abandoned (by the Martians)." Junkers forces rebuild outdated scraps from other Nations (i.e.: Soviet, China, Australia) in order to build their own vessels to some day join their people on Mars.
On the same page of WWR Complete, there is a second narrative that appears to be from the opposing perspective; that suggests that Junkers intentionally choose flight paths above highly populated Terran regions so that in the case that the launch fails there are Terran casualties. The failure rate in Junkers pilgrimage attempts is currently 97% chance of failure. The Terrans may also be suggesting this in attempt to manipulate the will and beliefs of the people of Earth.
The new term Neo Martians is also featured in this story.