Sooraj Shah ’24
Venus shares many similarities with Earth, including approximate size and mass. Venus’ surface temperature, however, is much hotter and contains a much thicker atmosphere consisting of carbon dioxide. For years, scientists have made estimates that Venus once was a thriving planet containing the resources for life like Earth. A research study led by astrophysicist Martin Turbet, in collaboration with the University of Geneva and the National Centre of Competence in Research, focused on developing models in order to simulate the formation of both Earth and Venus to uncover if Venus did indeed possess Earth-like conditions.
In order to make accurate predictions, the Laboratoire de Météorologie Dynamique (GCM), a device that functions as a research tool, forecasting planet conditions based on parameters set by researchers was used to create planetary models. The GCM utilizes features such as condensation, evaporation, sublimation, and precipitation to predict the conditions on the simulated planets. The simulations were run when the planets were still molten and at the beginning of formation. Both planets’ water content was completely vaporized due to the high temperatures. The simulations were then run from this point on, and the model was analyzed.
The results showed that the conditions of the atmosphere of Venus led to a different climate than that of Earth. The higher surface temperature of Venus prevented water vapor (present as steam in the beginning of Venus’ formation) from condensing into water and forming oceans as it did on Earth. In contrast, the lower temperatures on the dark sides of the planet form clouds, further preventing Venus from cooling and allowing no water to fall on the surface. This resulted in a global warming effect which has prevented Venus from hosting oceans.
The researchers also found that Earth may have been in the same situation if it had been in a different position relative to where it is now, and the main difference between the two planets was the inability for water to condense in the atmosphere and fall on the planet. This research is found to be crucial in understanding whether or not Venus truly is a twin planet of the Earth, and further research should be focused on modeling different scenarios in order to verify the results.
 M. Turbet, et al., Day–night cloud asymmetry prevents early oceans on Venus but not on Earth. Nature 598, 276–280 (2021). https://doi.org/10.1038/s41586-021-03873-w