Problem description:

Do fluorescent things glow by themselves?

Analysis:

Some are, some are not. Fireflies emit light through the chemical reaction between jellyfish luminescent protein and oxygen, some radioactive substances emit light through nuclear fission (and other invisible rays), mercury emits white light under ultraviolet irradiation (the principle of fluorescent lamps), and some heavy metals and rare metals also emit light (such as luminous watches), which is the reason for absorbing sunlight during the day.