Venus is the second planet from the Sun in the Solar System. It orbits the Sun once in about 224.7 Earth days. After the Moon, it is the brightest natural object in the night sky. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset.
Venus is classified as a terrestrial planet and is sometimes called Earth's "sister planet" owing to their similar size, gravity, and bulk composition.
About 80% of the Venusian surface is covered by smooth, volcanic plains, consisting of 70% plains with wrinkle ridges and 10% smooth or lobate plains.
Venus has the densest atmosphere of the four terrestrial planets, which consists mainly of carbon dioxide and a small amount of nitrogen.