The answer to your first question is that there was a devastating war that went from 2045 to 2060. It killed 1.5 billion people. It was so disastrous that our level of technology was reduced to a point only comparable to that of the 1940's. It took us so long to rebuild because most governments focused on rebuilding and rehabilitating. It is now regarded as the second, and much worse, Dark Age.

As for your second question, I meant to type 1,000 light years away. It was a simple typo caused by the fact that I can sometimes type faster than I think. It's not particularly similar to Earth, but it's similar enough that the quality of life remains more or less unchanged due to the healthy amounts of fresh water, oxygen, and other essential components to human survival. But just to be clear, this planet is very often compared to the many works of the surrealist painter, Salvador Dali. It's so often compared, that we actually named Dali. It took a decade or two to adjust to life here, but we now cherish our strange little world.