http://www.newsweek.com/next-naked-eye-comet-earth-long-wait-1775120

Comet C/2022 E3 (ZTF) is garnering increasing interest as it approaches Earth, with the object on the cusp of being visible to the naked eye under ideal conditions. But when might the next naked-eye comet appear following this event—and are astronomers even able to predict such phenomena?

Comets are astronomical objects made up of frozen gasses, dust and rock that orbit the sun. Sometimes referred to as "cosmic snowballs," these objects are blasted with increasing amounts of radiation as they approach our star, releasing gases and debris.