High Altitude Venus Operational Concept

The High Altitude Venus Operational Concept (HAVOC) is a mission concept studied by NASA for the long-term exploration of Venus. It proposes using crewed airships to explore the planet's atmosphere at an altitude of approximately 50 km (31 miles). At this altitude, the atmospheric pressure and temperature are similar to those found on Earth, making it a more hospitable environment for human exploration than the planet's surface.1

Venus possesses the most massive atmosphere of the terrestrial planets, composed primarily of carbon dioxide with a significant amount of nitrogen. The atmospheric pressure at the surface is about 95 times that of Earth's. The planet is enshrouded in thick clouds made of sulfuric acid droplets, extending from about 48 km to 68 km above the surface. These clouds reflect about 85% of the sunlight, contributing to a powerful greenhouse effect that raises the surface temperature to about 737 K (867 °F), hotter than the melting point of lead.2