Learn about the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission to Mars in this video from NASA's Goddard Space Flight Center. Mars does not have a global magnetic field like Earth but does have patches of magnetic fields. Scientists use magnetometers to study the planet's magnetic anomalies. The MAVEN spacecraft carries two magnetometers to investigate Mars's magnetic field in order to understand how the Martian atmosphere and climate has evolved over time. Because the magnetometers are extremely sensitive, engineers and scientists must take many precautions when developing the instruments and building the spacecraft.