Sunrise refers to the appearance of the sun rising out of the horizon or the sun that was originally seen. Generally speaking, the time when the sun rises from the horizon of the east is indeed defined as the moment when the sun has just emerged from the horizon, rather than the entire day leaving the horizon. At sunrise, the sun's rays are Rayleigh scattering caused by the dust in the Earth's atmosphere, so the sky will be filled with Xiaqi. However, the sunrise is more elegant than the sunset, because the dust in the atmosphere at sunrise. Less than at sunset. Because the sun's rays are refracted by the Earth's atmosphere, when the sun has not yet risen to the horizon, people have seen the scenery of the sunrise, which is the illusion that occurs every sunrise. Ancient Chinese astronomers have recorded a rare astronomical phenomenon called "Tian Zaidan", meaning that there were two consecutive sunrises on the same day. Usually due to the astronomical spectacle caused by the total solar eclipse from 5 am to 7 pm, the first sunrise, the sky gradually darkened, and then greeted the second sunrise.