The Zooniverse, a platform for online people-powered research, has reached 1 billion classifications contributed by volunteers worldwide. Volunteers have contributed to various research projects by completing tasks such as marking light curves and confirming moving objects. This milestone celebrates the efforts of volunteers who have helped advance scientific research through their contributions.

Source: https://science.nasa.gov/get-involved/citizen-science/nasa-volunteers-help-zooniverse-reach-1-billion-classifications/