Part of Nebulae · 4 / 4
Shells
Nebulae #4. After the Cat's Eye Nebula. A dying star throws off a shell once every period. Each shell is a soft ripple in domain-warped gas that travels out from a precessing centre, swells unevenly and thins as it ages, so the rings are a record of the rhythm. One loop is one period: a shell is born at the centre as the oldest dissolves at the edge. Inside, two bipolar lobes.