Titan, Saturn’s most metal moon, has become even more fascinating. The moon experiences a unique phenomenon where clouds of methane produce a cold, oily rain, a stark contrast to the water-based rain seen on Earth. For the first time, scientists have gathered evidence of cloud convection in Titan’s northern hemisphere, observing the moon’s methane clouds shifting over time above its eerie lakes.

By combining data from the Webb space telescope and the Keck Observatory in Hawaii, a team of scientists observed Titan’s clouds rising to higher altitudes over time. This groundbreaking discovery marks the first time cloud convection has been observed in the moon’s northern hemisphere, where most of Titan’s lakes and seas of liquid methane are located. The findings are detailed in a study published in the journal Nature this week.

According to Conor Nixon, research scientist with NASA Goddard Space Flight Center and lead author of the study, “This discovery allows us to better understand Titan’s climate cycle, including how methane clouds may generate rain and replenish methane evaporated from the lakes.” Nixon made this statement in a statement.

Titan, the only moon in the solar system with a substantial atmosphere, is shrouded in a layer of yellowish smog. To probe different depths in Titan’s atmosphere, the scientists utilized various infrared filters on Webb and Keck to estimate the altitudes of the clouds. The team behind the study observed Titan in November 2022 and July 2023, capturing clouds in the moon’s mid and high northern latitudes. By using space and ground-based observations, the scientists observed the clouds as they appeared to move to higher altitudes over a period of days, although they were unable to directly observe any precipitation occurring.

Titan is the only other place in our solar system known to have an Earth-like cycle of liquids, where rain pours from clouds, flows across its surface, fills lakes and seas, and evaporates back into the sky, according to NASA. However, instead of water, Titan has liquid methane and ethane.

The moon is of great interest to astronomers due to its complex organic chemistry, despite its extremely cold temperatures and gaseous bodies of water. Organic molecules, which are the building blocks of life on Earth, can provide valuable insights into how different lifeforms could evolve under drastically different planetary conditions. Studying Titan helps scientists better understand this process.

These recent findings also shed light on how different worlds evolve over time. As Nixon explained, “On Titan, methane is a consumable. It’s possible that it is being constantly resupplied and fizzing out of the crust and interior over billions of years. If not, eventually it will all be gone, and Titan will become a mostly airless world of dust and dunes.”