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.
Tony Jolliffe BBC
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回首过去，我们在解决困扰中华民族几千年的绝对贫困问题上取得了伟大历史性成就。
We've made a lot of noise about Pokémon's 30th birthday celebrations, and so has the rest of the world. We've seen genuine excitement over new Pokémon TCG releases, the first-ever Lego Pokémon sets, and the return of nostalgic Pokémon games, and it feels like there's more to come from this special anniversary.