A team of researchers studying exoplanets has discovered that clouds on lava planets can significantly affect their surface temperatures. According to the research, published on the preprint server arxiv.org, daytime temperatures on these planets are high enough to support the existence of a magmatic ocean and silicate atmosphere, making them ideal objects for studying the atmospheres of rocky planets.

Lava planets are characterized by extremely high temperatures on their surfaces, which can reach several thousand degrees Celsius. This is due to their close proximity to their star and the resulting strong heating. Unlike Earth, where its surface continues to receive heat from the atmosphere and oceans at night, lava planets have no heat sources at night. On lava planets, the entire atmosphere collapses near the day-night boundary, resulting in a sharp temperature difference between the day and night sides of the planet. As a result, the temperature on the night side of the planet can be much lower than on the day side, leading to the formation of clouds and other atmospheric phenomena.

However, the influence of clouds on the observed radiation, dynamics and transfer of values ​​in a non-spherical atmospheric regime remains uninvestigated.

The researchers modeled the formation of clouds and determined which lava planets were most susceptible to the effects of clouds. They found that despite cloud scattering of visible light, heat conduction offsets the cooling effect of clouds in the atmosphere. However, surface temperatures can suffer significantly, dropping by 100–200 K under cloudy skies.

Of the targets studied, planets HD213885 b and HD20329 b were found to be the most prone to cloud formation. There is a noticeable difference between the presence and absence of clouds, but the precision required to draw such a conclusion is beyond the capabilities of current instruments.

This discovery is important for understanding the atmospheres of rocky planets and could help develop more accurate models for studying them. Additionally, the results of the study could also impact the search for potentially habitable planets, as clouds can significantly affect the climate and conditions on the planet’s surface.