Late Friday night, two sounding rockets launched from a small spaceport in northern Norway. The two skinny rockets soared to an altitude of 320km, and along the way each released a visible gas intended to disperse through and illuminate conditions inside the aurora borealis. Some of the resulting images were stunning.

This NASA-funded AZURE mission, which stands for Auroral Zone Upwelling Rocket Experiment, is one of a series of sounding rocket missions launching over the next two years as part of an international collaboration known as "The Grand Challenge Initiative – Cusp." The goal of these flights is to study the region where Earth's magnetic field lines bend down into the atmosphere, and particles from space mix with those from the planet.

Friday night's mission involved two Black Brant XI-A rockets, a three-stage sounding booster with a long heritage dating back to Canadian military research in the 1950s. The Black Brant rockets launched within two minutes of one another from the picturesque Andøya Space Center in Norway, beginning at 22:14 UTC Friday.

Time-lapse of @nasa AZURE mission launching 2 sounding rockets from @AndoyaSpace about 4 hours ago. They created glowing clouds (background is real aurora) to study and track the flow of particles in the ionosphere @NASA_Wallops @TamithaSkov @StormHour @chunder10 @B_Ubiquitous pic.twitter.com/sFiCCP9LdY — Adrien Mauduit (@ADphotography24) April 6, 2019

After their launch, the two rockets ascended into space while onboard instrumentation measured the atmospheric density and temperature in order to determine the ideal time to release visible tracers—trimethyl aluminum and a barium/strontium mixture. These gas tracers were released at altitudes varying from 115 to 250km.

The gases ionized as they fell through the atmosphere, which produced colorful clouds that allowed researchers to better understand the flow of particles in the ionosphere (the upper part of Earth's atmosphere that forms the boundary between the planet and outer space). For observers below, the tracers also put on quite a visible show.

By studying the movement of particles within the aurora borealis, scientists hope to better understand how the energy of these phenomena affect atmospheric behavior.

Listing image by Andoya Space Center