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This intense radiation ionizes the expelled gas, producing vibrant colors: red hues from ionized hydrogen and greenish patches from ionized oxygen. The central white dwarf is remarkably hot, radiating primarily in ultraviolet, making it invisible in the visible spectrum.
Remarkably, internal winds from this core accelerate at speeds exceeding 1,000 km/sec, creating waves and expanding the nebula's structure. Observing these phenomena provides insights into stellar evolution stages that lead to planetary nebula formation.