The Northern Lights are more than just something pretty to look at on your next Canadian camping trip. They indicate changes in our planet’s magnetic field and potential threats from solar flares. Scientists think Northern Lights can tell us even more, but to find out, they’ll need to do something that until now has been impossible: create one.
The Earth’s atmosphere is filled with layers. The bottom layer—where those of us who don’t live in cloud cities spend most of our time—is called the troposphere. Above that is the stratosphere, the domain of aircraft and high-altitude balloons. Above that is the ionosphere, which is the highest layer of our atmosphere, and which sits at the border between our planet and space. The ionosphere is where high-energy cosmic rays collide with our atmosphere and the Northern Lights appear.
Above the ionosphere is the Earth’s magnetosphere, an area that marks the border of Earth’s magnetic field. In this region between the Earth’s atmosphere and space exist extremely complicated interactions between the magnetosphere, the ionosphere, and particles from the Sun.
When the Sun emits solar material—for instance, during a solar flare or as part of the solar wind—those particles fly through space and hit the Earth’s magnetosphere. The pressure exerted by these materials distorts the magnetosphere, bringing it in contact with the ionosphere. When that happens, the entire atmosphere lights up, and you get Northern (or Southern, for our Southern Hemisphere friends) Lights.
Scientists understand this part of the process, but how the magnetosphere creates auroras is mostly a mystery. When a particle from the Sun hits the magnetosphere, it lights up a corresponding part of the ionosphere with an aurora, but there’s no way to tell which part of the magnetosphere is connected to which part of the ionosphere.
That’s exactly what an upcoming satellite experiment is designed to figure out. The CONNection EXplorer—or CONNEX for short—consists mainly of a satellite that will fire electron particles at the planet. Those particles will be captured by the magnetosphere and make it to the ionosphere as artificial aurora. Because we know exactly where those particles are hitting the magnetosphere, CONNEX lets us map different parts of the ionosphere to different parts of the magnetosphere.
“We maybe see very interesting dynamics [in the magnetosphere] and we see very interesting dynamics [in the ionosphere],” says CONNEX team member Gian Luca Delzanno, of Los Alamos National Laboratory. “But we cannot really say whether one is the cause of the other simply because we do not know where those phenomena [in the magnetosphere] map to in the ionosphere.”
The information collected through CONNEX should allow scientists to develop a better understanding of what happens in the magnetosphere. That’s important because the magnetosphere can seriously affect the operation of spacecraft and satellites.
“If that was possible then we could say, ‘Maybe something else is happening away from the Earth and some spacecraft could be in danger, so let’s shut them off,’” says Delzanno.
The project is still in the very early stages of development. So early, in fact, that the team of scientists working on it—from half a dozen universities, a handful of national labs, and a few private institutions—are currently putting together a NASA proposal. If CONNEX receives funding, it will join other recent NASA-funded missions such as WISE and TESS.
CONNEX is only the first step, but if it works, scientists could unlock a whole new way to study the space around the Earth.
Originally posted on Popular Mechanics