NASA
Like other scientific organizations, NASA conducts most of its measurements in the international system (metric system). This is partially due to federal law requiring that most US government programs be done in the international system. In the 1980s, NASA transitioned to the metric system, but was still using US customary \ imperial units into the 1990s. In September 1999, a mixup (or mistake) between imperial and metric units resulted in the loss of the Mars Climate Orbiter.