The technological changes were small at first. In 2007 a telescope was developed that could search for planets in the Milky Way within 100 light years of Earth. The next version of the telescope in 2008 did not have to block out the light of the new star to see the planets. It could directly see the reflected light of the planets closest to every star. That made it possible to do spectroscopic analysis of reflected light and search for blue planets like Earth. Within a decade, 100 Earth-like planets had been identified within 100 light years. In the next two centuries that number increased to 50,000 blue planets.
Within the next two centuries the seemingly impossible technical problems of space travel began to be solved. Problems of foil sails were solved. Designs emerged for ships that could get up to 85% of the speed of light within 2 years, using acceleration from starts and from harnessing the creative energy of empty space itself. The Moon, Europa and Mars were colonized. Terra-forming technologies developed. Many designs emerged for the spinning complete 2-mile Earth-habitat ship that produced a 1-g environment. Thousands of people wanted to make the trips.
Laboratory Earth colonies were formed for simulating conditions for the galactic trips. Based on these experiments, social scientists soon recognized that the major unsolved problem of galactic colonization was the social psychological problem, How could humans live together for up to 52 years, raising children who would become the explorers of the blue planets? Much had been learned, of course, from the social psychological studies early in the 21st and 22nd Centuries for obtaining planet-wide cooperation in solving global warming and sustainable energy production, and in curing world-wide hunger and disease. But that work was primitive and rudimentary for the challenges of galactic colonization.
The subsequent classic social psychological studies were all funded privately by one man. Thousands of scientists participated. Studies of all kinds were initially devised, and the results were carefully replicated. The entire series of social psychological experiments took a century to perform. It rapidly became clear that a military or any hierarchical social structure could not last without the threats of continual external danger. The work of Peggy Sanday had demonstrated that fact without question. The problem was to foster creative collaboration and minimize self-interest. Eventually, it was deemed necessary for each ship to spend 5 years prior to the trip selecting a problem that all the members would creatively and cooperatively face. The work had to easily consume the crew of a ship for 60 years. In addition, each ship represented a microcosm of all Earth's activities, including all the occupations and professions, adventure, play, and sports.
In the year 2,500 more than 20,000 ships set out, 2 headed for each planet. It was inevitable that many ships would successfully make the journey. No one knew what they would find. There was no plan for communication between the stars. The colonization of the Milky Way had begun.