Beyond the cloud's unusual shape, scientists see the nebula as a freeze-frame in the life of a star facing its final act. Elderly stars shed their outer layers in bursts, creating shells of gas and dust that expand. By observing the nebula at different wavelengths, researchers can sort out what material was molted first, how fast the star is losing mass, and which phase of decline Webb has caught.
recognition. This format remains in use today, to the extent that checks remain
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if (n <= 1) return;