In 2004, over 70,000 Dutch children participated in the Seeds in Space experiment. They sowed rocket/arugula seeds in a rocket-shaped kit here on Earth, while ESA astronaut André Kuipers sowed his on board the International Space Station. The kits had light and dark chambers, to compare the growth of the seeds in the presence or absence of light. The seeds in the dark chamber grew taller, but were yellow. In the light chamber, the seedlings were shorter, with wider stems and a healthier green colour. The experiment was organised by Space Research Organization Netherlands (SRON).