SpaceX, NASA to launch 1st mission to study aurora ‘electrojets’ in Earth’s atmosphere

Every second, phenomena known as “auroral electrojets” that stem from solar activity push about a million amps of electrical charge around Earth’s poles — and that electrical charge can create big problems.

Electrojets are intense electric currents that flow above the Earth. Magnetic disturbances from auroral electrojets can lead to power outages on our planet, for instance, impact astronauts’ safety, and interfere with satellites.

Now, NASA has a plan to study these powerfully disruptive currents, with hopes of managing their potential effects. In March, the EZIE (Electrojet Zeeman Imaging Explorer) mission will launch three suitcase-sized satellites, called cubesats, aimed at tracking the troubling phenomena.

An illustration of three satellites above Earth looking down at bright green auroras. — An artist’s representation of the EZIE troop of satellites. (Image credit: NASA/Johns Hopkins APL)

“EZIE is the first mission dedicated exclusively to studying the electrojets,” Larry Kepko, an EZIE mission scientist at NASA’s Goddard Space Flight Center in Maryland, said in a statement. “It does so with a completely new measurement technique.”

In particular, the mission relies on the Zeeman technique. Here’s how it works

Tracking spaceborne currents

Molecules of the element oxygen usually emit microwave radiation at a frequency of 118 gigahertz, and the important thing here is that oxygen molecules exist around our planet. Meanwhile, electrojets create a magnetic field around our planet — and this field can split the 118 gigahertz emission line associated with those oxygen molecules. The process is called Zeeman splitting. When the magnetic field is stronger, this emission line is split further apart.

Using an onboard instrument called a microwave electrojet magnetogram, the three EZIE cubesats will observe the Zeeman splitting effect while orbiting the Earth.

NASA will then study the strength and direction of the observed magnetic fields created by the electrojets. Their scientists hope this will reveal the structure and evolution of the electrojet system.

“The utilization of the Zeeman technique to remotely map current-induced magnetic fields is really a game-changing approach to get these measurements at an altitude that is notoriously difficult to measure,” Sam Yee, EZIE’s principal investigator at the Johns Hopkins Applied Physics Laboratory (APL), said in the same statement.

Notably, the EZIE mission will tap into the power of citizen scientists to enhance its research. By distributing dozens of EZIE-Mag magnetometer kits to U.S. students, as well as volunteers worldwide, NASA will be able to compare lots of data gathered on Earth with EZIE’s observations.

“EZIE scientists will be collecting magnetic field data from above, and the students will be collecting magnetic field data from the ground,” Nelli Mosavi-Hoyer, EZIE project manager at APL, said in the statement.

A SpaceX Falcon 9 is scheduled to launch the three EZIE CubeSats from Vandenberg Space Force Base in California with the Transporter-13 rideshare mission. The launch will happen during solar maximum, when activity from the sun is stronger and more frequent. “It’s better to launch during solar max,” Kepko said. “The electrojets respond directly to solar activity.”

Other NASA heliophysics missions, like PUNCH (Polarimeter to Unify the Corona and Heliosphere), will work alongside the EZIE mission. PUNCH, which is scheduled to launch this week, will study how material in the sun’s outer atmosphere turns into the solar wind.

“We’re leveraging the new capability of cubesats,” Kepko said. “This is a mission that couldn’t have flown a decade ago. It’s pushing the envelope of what is possible, all on a small satellite. It’s exciting to think about what we will discover.”