A few days ago, two Black Brant XI-A probe rockets were launched from a small cosmodrome in Northern Norway at intervals of two minutes. After reaching an altitude of 320 km, they released a tracer - a special scattering gas whose task was to illuminate the northern lights. This gave an incredible and stunning color effect.
The launch was carried out as part of the NASA-funded AZURE mission, designed for two years. Its full name is "Auroral Zone Upwelling Rocket Experiment". It is part of a series of grandiose missile missions as part of a larger international project, The Grand Challenge Initiative - Cusp. The purpose of the flights is to study the region of the atmosphere where the lines of the planet's magnetic field are bent, and cosmic particles come into contact with earthly ones.
After reaching the specified altitude in the range from 115 to 250 km, the probe instruments measured the density and temperature in order to determine the optimal time for the emission of tracers - trimethylaluminum and a mixture of barium with strontium - into the atmosphere.
Once in the atmosphere, the gases ionized and turned into colorful clouds, allowing researchers to better understand the direction of particle flows in the ionosphere. By studying the movement of particles within the northern lights, scientists hope to better understand how the energy of these phenomena affects the state of the Earth's atmosphere.