Chinese astrology or Korean astrology only uses the first five planets

In Korean, the names of the planets up to Saturn follow a naming convention based on the Five Elements (wood, fire, earth, metal, water) from Chinese philosophy, which is deeply integrated into East Asian cultures. This system aligns with ancient Chinese astronomy and has been adopted in various forms across East Asia, including Korea. The names for Mercury (수성, Su-seong, "Water Star"), Venus (금성, Geum-seong, "Metal Star"), Mars (화성, Hwa-seong, "Fire Star"), Jupiter (목성, Mok-seong, "Wood Star"), and Saturn (토성, To-seong, "Earth Star") reflect this elemental association.

However, the names for Uranus (천왕성, Cheonwang-seong, "Heavenly King Star") and Neptune (해왕성, Haewang-seong, "Sea King Star") do not follow this convention. This divergence is because Uranus and Neptune were discovered much later than the first five visible planets (Mercury, Venus, Mars, Jupiter, Saturn) and therefore were not integrated into the ancient naming system based on the Five Elements. Instead, their names were chosen to reflect more contemporary or Western astronomical traditions at the time of their discovery and subsequent introduction into East Asian cultures. The names for Uranus and Neptune in Korean, like in many other cultures, were inspired by the Roman gods Uranus (the god of the sky) and Neptune (the god of the sea), which were then translated or adapted to fit Korean language and cultural context.