While clouds are made of water on Earth, their composition is quite different on other distant planets. Scientists have noted that some of these planets have sandy clouds of silicate, but have not been able to pinpoint the conditions under which they form. Now, a new study has uncovered a common trait that favors sand cloud development. Led by researchers at Western University, the study used observations of brown dwarfs made by NASA’s retired Spitzer Space Telescope. Brown dwarfs are celestial bodies whose size is larger than a planet but smaller than a star.
“Understanding the environments of brown dwarfs and planets where silicate clouds can form can also help us understand what we would see in an atmosphere. The planet It is close in size and temperature EarthProfessor Stanimir Metchev said exoplanet study at Western University in London, Ontario, and co-author of study,
Any type of cloud is formed where the main component heats up to form vapor. Once the component — which can be anything from water, salt, sulfur, or ammonia — becomes trapped and cools, clouds form.
The same principle is involved in the formation of silica clouds but since high temperatures are required to vaporize the rock, such clouds are found only on hot celestial bodies such as brown dwarfs. The researchers included brown dwarfs in their study because many of them have atmospheres similar to gas-dominated planets such as Jupiter,
Spitzer Telescopes had already seen traces of silica clouds in the atmospheres of some brown dwarfs. However, the evidence was not solid enough. In the new study, the researchers used more than 100 detections and grouped them according to the temperature of the brown dwarfs. This helped them to determine a certain characteristic and temperature range in which silica clouds form.
“We had to dig through the Spitzer data to find these brown dwarfs where there were some signs of silicate clouds, and we didn’t really know what we would find,” said lead author Gennaro Suárez.