Today, a paper published in Science documents for the first time the global wind circulation patterns in the upper atmosphere of a planet, 120 to 300 kilometers above the surface. The findings are based on local observations, rather than indirect measurements, unlike many prior measurements taken on Earth’s upper atmosphere. But it didn’t happen on Earth: it happened on Mars. On top of that, all the data came from an instrument and a spacecraft that weren’t originally designed to collect wind measurements.

In 2016, Mehdi Benna and his colleagues proposed to the Mars Atmosphere and Volatile EvolutioN (MAVEN) project team that they remotely reprogram the MAVEN spacecraft and its Natural Gas and Ion Mass Spectrometer (NGIMS) instrument to do a unique experiment. They wanted to see if parts of the instrument that were normally stationary could “swing back and forth like a windshield wiper fast enough,” to enable the tool to gather a new kind of data.

Initially, the MAVEN project team was reluctant to implement the modifications Benna and his colleagues requested. After all, MAVEN and NGIMS had been orbiting Mars since 2013, and they were working quite well collecting information about the composition of the Mars atmosphere. Why put all that at risk? Benna and his colleagues argued that this project would collect new kinds of data that could shape our understanding of the upper atmosphere on Mars, inform similar studies on Earth, and help us better understand planetary climate.