Venus is the brightest natural object in the night sky after the Moon. At its brightest, it reaches an apparent magnitude of about −4.9, making it far brighter than Jupiter, Mars, or Sirius.
Venus shines so strongly because it is close to Earth and covered by highly reflective clouds made mostly of sulfuric-acid droplets. It is an inner planet, orbiting closer to the Sun than Earth does, so it never appears opposite the Sun in our sky. Instead, it is seen near sunrise or sunset as the “morning star” or “evening star.”
Venus is not a star, despite those traditional nicknames. Its brilliance comes from reflected sunlight, not from nuclear fusion. Sirius is the brightest star seen at night, while Jupiter can sometimes rival Venus but normally appears less bright from Earth.
The planet’s brightness and predictable position made Venus important in ancient skywatching traditions. Its two appearances were once often treated as separate objects before astronomers recognized that the morning and evening stars were the same planet.