If you ever listen to the radio and experience a phenomenon in which the broadcast sounds garbled or as if another radio station is attempting to play over yours, then you’ve likely experienced something called a Sporadic-E Layer. In a nutshell, this is a concentration of plasma residing in Earth’s ionosphere that behaves much like a mirror for radio transmissions that occur between them and the ground.
Studying Sporadic-E Layers on Earth is a challenge because they transpire at altitudes where the air is much too thin to fly an aircraft, and conversely, much too thick to orbit a spacecraft. That said, the rather troublesome circumstances have compelled NASA to study the phenomenon on another planet where the ionosphere isn’t as thick, and this makes Mars a great target for such observations.
With the help of an instrument called Static on NASA’s MAVEN Martian orbiter, the American space agency is able to study Sporadic-E Layer activity in the red planet’s ionosphere. Static has been specially designed to measure plasma escaping from Mars’ ionosphere, and because the air there is so much thinner, MAVEN is able to orbit without the risk of deorbiting as a similar spacecraft would here on Earth.
While studying these atmospheric plasma occurrences on Mars, scientists took notice that they were somewhat predictable, if not permanent. This behavior contrasts greatly to that of Earth, where plasma occurrences are sporadic and seemingly unpredictable.
Given just how little we know about ionospheric plasma, MAVEN promises to unlock secrets that we only could have imagined studying here on Earth. Isn’t science grand?