The planet with active volcanoes is Venus. Although Earth's volcanoes are well-studied, Venus exhibits significant volcanic activity; geological evidence suggests that its surface has undergone numerous eruptions over time. The planet's thick atmosphere, composed mostly of carbon dioxide, contributes to high surface temperatures and pressures that may facilitate the melting of subsurface rock. The presence of large volcanic structures, such as coronas and volcanic plains, indicates that lava flows and possibly explosive eruptions have occurred on Venus, but the planet's hostile conditions make direct study challenging.