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Why does white phosphorus glow in the dark?

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Diagram showing the element phosphorus on the periodic table, with its atomic number 15, symbol P, atomic weight 30.973762, electron configuration, cubic crystal structure, solid state at room temperature, and weakly acidic oxides.
phosphorus

White phosphorus is a chemical element that is known for its ability to glow in the dark. It is important to clarify that this phenomenon is not a form of phosphorescence, but rather a result of its high chemical reactivity.1

White phosphorus is a metastable, highly reactive solid that oxidizes when exposed to air. The glow observed in the dark is caused by the slow oxidation of the phosphorus vapor in the presence of oxygen. This process is a form of chemiluminescence, where light is emitted as a direct result of a chemical reaction. Because white phosphorus is highly toxic and inflames in air at temperatures as low as 35 °C (95 °F), it must be handled with extreme care and stored under water or an inert liquid to prevent unintended combustion.2345