Auroras form when charged particles from the solar wind are funneled by Earth's magnetic field into the upper atmosphere, where they collide with oxygen and nitrogen atoms and excite them to emit green, teal, purple and blue light along field-aligned "curtains." Here each curtain is a single PlaneGeometry strip driven by a custom ShaderMaterial: the vertex shader offsets vertices with sine/cosine waves for organic ribbon motion, while the fragment shader layers 2D value-noise to fake shimmering plasma and fades it with vertical/horizontal smoothstep masks. A separate point-based ShaderMaterial twinkles the background starfield by animating per-star sine brightness.