A Johns Hopkins Applied Physics Laboratory-led mission to explore electric currents in Earth‘s atmosphere that link the aurora to our planet‘s magnetosphere has been selected by NASA to move forward to a scheduled launch in 2024.

The Electrojet Zeeman Imaging Explorer, EZIE, is a set of three small spacecraft that will study the auroral electrojet, which are electrical currents flowing about 60 to 90 miles above the poles that link the beautiful aurora to the Earth‘s magnetosphere, and which responds to solar activity and other drivers.

The interaction of the magnetosphere and the solar wind—one piece of Earth‘s complicated space weather system—compresses the Sun-facing side of the magnetosphere and drags out the nighttime side of the magnetosphere into what is called a "magnetotail." Auroral electrojets are generated by changes in the structure of the magnetotail. The same space weather phenomena that power the fascinating aurora can cause interference with radio and communication signals and utility grids on Earth‘s surface, and damage to spacecraft in orbit.

"Despite decades of research, we still don‘t understand the basic configuration of the electrical currents which are central to the interactions between Earth and the surrounding space," said Jeng-Hwa (Sam) Yee, chief scientist in Earth Science at APL and principal investigator for the mission. "This is a problem of universal importance since it applies to any magnetized body such as Mercury, Saturn and Jupiter — but it also has practical importance since these currents have a profound impact on our technologies in space and here on Earth."