Use the supplied original dark image as the first frame, with one mint glowing point near the lower left and four muted non-emitting background markers. Keep the camera and all four background markers fixed. Move the same single solid light center along one short smooth curve toward the upper right, then stop. A soft temporary trail forms only behind positions the source has already passed. Older parts of that trail gradually become weaker than newer parts nearer the moving source. Keep exactly one solid emitter; do not leave a row of copied solid light balls, create a branching path, draw a permanent line or place the trail ahead of the motion. After the emitter stops, the old trail continues fading until only the one endpoint light remains. Do not cut or replace the background to hide the fading. This is an untested visual-effects request, not a physical particle simulation, exact lifetime or frame-by-frame opacity guarantee.