Nasa Astronaut Data detail
Each line represented total flight hours represented in chunks by size of circle [250, 100, 50, 10, 1]. http://tiffanyfrance.com/data-is-beautiful/18-11/
Each line represented total flight hours represented in chunks by size of circle [250, 100, 50, 10, 1]. http://tiffanyfrance.com/data-is-beautiful/18-11/