This scatter plot displays the number of space missions per year, with each country (USA, Russia, China, Kazakhstan) represented by a distinct color. An interactive color legend allows hovering over a country name to highlight its corresponding circles while fading others. The visualization uses D3 scales (`scaleTime`, `scaleLinear`, `scaleOrdinal`) and React components for rendering SVG circles grouped by year. Data comes from a Kaggle CSV file processed with D3’s `csv` and `nest` functions, with axes and legend developed as custom React components.