Reconstruct the History and Origin of Venus’s Atmosphere and Climate

Establish when and how Venus’s current atmosphere and climate developed; determine whether the atmosphere is a relict primordial atmosphere or whether Venus previously experienced clement, Earth-like conditions; and ascertain when and why Venus’s climate diverged from Earth’s.

Background

Understanding the origin and evolution of Venus’s dense CO2 atmosphere and extreme climate is pivotal for comparative planetology and assessments of planetary habitability. The report highlights uncertainty over whether Venus retained a primordial atmosphere or transitioned from a past clement state.

Resolving the timing and causes of Venus’s climatic divergence from Earth would elucidate key processes—such as volcanic outgassing, atmospheric escape, and surface–atmosphere interactions—and provide crucial constraints for interpreting Earth-sized exoplanets.

References

...we do not know when or how this atmosphere and current climate developed—is it a relict primordial atmosphere, or was Venus once far more clement and perhaps even Earth-like? If not, why not? If so, when and why did Venus’ climate diverge so drastically from that of Earth?

— A New Strategy for the Exploration of Venus  (2412.06830 - Workgroup, 2024) in Overview of Venus’s atmosphere (early section), two consecutive sentences following the description of trace gases

The reason for the occurrence of the trend at deeper altitudes remains unknown.

— Study on the Venusian Atmospheric Thermal Structure: A Comparative Analysis between VEX/Akatsuki and Venus-GRAM/VCD  (2608.26768 - Banerjee et al., 27 Aug 2026) in Section 4, Discussion and Concluding remarks