The second component of the corona is the F corona, a cloud made of tiny grains of dust and presented in this Chapter. It extends from above the surface of the Sun to far away from it, since it reaches the Earth orbit or even beyond. At such distances, if is also named the zodiacal cloud, as it corresponds to the zodiacal light observed on Earth after sunset or before sunrise when circumstances are favourable. These grains of dust are mixed with the gaseous component (K), but the density of the corona is so small that these grains remain at temperatures less than about 1000°C, while the surrounding gas is at 1 million degrees. The main origin of these grains can be attributed to the evaporation of comet nuclei, made of a mixture of ices and dust grains, when they come close to the Sun and warm up. Observations and understanding of comets have made great progress with the advent of telescopes in space. Therefore, the size and nature of the grains released in interplanetary space is today better understood.