First results from 2021 rocket launch shed light on aurora’s birth

The Kinetic Scale Energy and Momentum Transfer Experiment – KiNET-X – lifted off from NASA’s Wallops Flight Facility in Virginia on May 16, 2021, at the end of the final night of the nine-day launch window few minutes.

UAF Professor Peter Delamere’s analysis of the experimental results was published on November 19 plasma physics.

“Bright lights are incredibly complex,” Delamere said. “A lot is going on there, and a lot is going on in Earth’s space environment, to cause what we observe.

“It’s extremely difficult to understand cause and effect in the system because we don’t know what exactly is happening in space to cause the light we observe in auroras,” he said. “KiNET-X is a very successful experiment that will reveal more of the aurora’s secrets.”

One of NASA’s largest sounding rockets flew across the Atlantic Ocean and entered the ionosphere, releasing two canisters of barium thermite. The canisters were then detonated, one at an altitude of approximately 249 miles and the other 90 seconds later on a descent trajectory approximately 186 miles near Bermuda. The resulting cloud was monitored by a NASA research aircraft on the ground in Bermuda.

The aim of the experiment was to replicate on a tiny scale an environment in which the low energy of the solar wind changes to high energy, creating fast-moving and flickering curtains called discrete auroras. Through KiNET-X, Delamere and his colleagues in the experiment are closer to understanding how electrons are accelerated.

“We created charged electrons,” Delamere said. “We just didn’t generate enough electrons to create the aurora, but there are fundamental physics related to electron excitation in the experiment.”

The aim of the experiment was to create Alfvén waves, a type of wave that exists in magnetized plasma such as those found in the Sun’s outer atmosphere, Earth’s magnetosphere and elsewhere in the solar system. Plasma – a form of matter composed primarily of electrically charged particles – can also be produced in laboratories and experiments such as KiNET-X.

Alfvén waves are produced when disturbances in the plasma affect the magnetic field. Plasma disturbances can be caused in a variety of ways, such as through a sudden injection of particles from a solar flare or the interaction of two plasmas of different densities.

KiNET-X creates Alfvén waves by injecting barium into the far upper atmosphere to disturb the surrounding plasma.

Sunlight converts the barium into ionized plasma. The interaction of two plasma clouds creates Alfvén waves.

Alfvén waves immediately produce electric field lines parallel to the Earth’s magnetic field lines. And, as the theory goes, the electric field significantly accelerates the electrons on the magnetic field lines.

“It shows that the barium plasma cloud briefly combines with the ambient plasma and transfers energy and momentum to the ambient plasma,” Delamere said.

This transfer manifests itself as a small beam of accelerated barium electrons shot toward Earth along magnetic field lines. This beam is only visible in the experiment’s magnetic field line data.

“It’s similar to an auroral electron beam,” Delamere said.

He called it the “golden data point” of the experiment.

Analysis of the different hues of the beam, visible only in green, blue and yellow pixels in the Delamere image, can help scientists understand what happens to the particles that create the dancing northern lights.

The results so far show a successful project that can even glean more information from its previous experiments.

“It’s a matter of trying to piece together the whole picture using all the data products and numerical simulations,” Delamere said.

Three UAF students conducting doctoral research in the UAF Institute of Geophysics also attended. Matthew Blandin provides optical operations support at Wallops Flight Facility, and Kylee Branning works on NASA’s Gulfstream III, also at Langley Research Center in Virginia. Nathan Barnes operated the camera from the aircraft and assisted with computer modeling in Fairbanks.

The experiment also includes researchers and equipment from Dartmouth College, the University of New Hampshire, and Clemson University.