What is a skywriter? What does it do exactly?

The sky burial is a traditional way of burial for ethnic minorities such as the Mongols and Tibetans. After death, the body is taken to a designated place to be devoured by an eagle (or other birds or animals), which is believed to be taken to heaven. Like earth burial, water burial and cremation, it is a kind of belief, a way of expressing one's faith in the dead, and is essentially a social and cultural phenomenon, whose origin, form, content and implementation of the rituals are all influenced by the natural geographic environment and the way of life as well as by foreign cultures and other factors. Therefore, different sky burial ceremonies are formed in different historical periods, different countries and regions, different ethnic groups and even different social classes. There are records about sky burial in ancient Chinese books. For example, "Ancient burials were done in thick clothes with pay, buried in the middle of the field, without sealing or trees" - Zhouyi - The Biography of the Department of Rhetoric, "Gai Shang also tasted those who did not bury their relatives, whose relatives died by lifting up and entrusting them to the gully. When he passes by in the next day, foxes will eat them and flies and mosquitoes will sip them." --Mengzi ˙Teng Wengong Shang (孟子˙滕文公上). In some areas of modern society the ritual of sky burial still exists among the people. For example, in Tibet, the sky funerer turns the corpse's back toward the sky, breaks off the limbs, tears the skin in the center of the corpse and the shoulders to reveal the muscles, and then backs away as vultures come down from the sky to peck at it. When the skeleton is left on the funeral pyre, the undertaker will use a stone to knock the skeleton into bone paste and knead it into a ball, and the vultures will once again come down from the sky, and when they have eaten all the food and dispersed, the people around them will start kneeling down and bowing down in reverence. Another example is living in the eastern region of Africa, the Maasai people, they will be dead after the death of the whole body washed with water, carefully coated with a layer of cream, placed in the center of the house, the relatives of the silent kneeling around the body to do a day of prayers, and then the village elders to lead the way, the people carry the body to the wilderness, the remains will be placed there, let the beasts devour, birds gripping peck, which indicates that the Maasai people die also different from the land bond. Another example is the Parsi people in India, who still have a sky burial ceremony. Among the Parsis, "the great majority of the members still believe in Zoroastrianism and maintain their original living customs". In the surviving classic of Zoroastrianism, the Zend-Areta, it is written that the Zoroastrians "place their dead on the tops of mountains infested with birds and beasts and let them eat the beaks of the birds".