At the north pole of Saturn’s largest moon Titan lie the largest (and only known) bodies of surface liquid in the Solar System outside of Earth. But on Titan, where temperatures are regularly around negative 300ºF, the liquid isn’t water but rather methane and ethane: compounds which are found as gases here on Earth. Titan’s seas and lakes are exotic environments that scientists are only just starting to understand, and even with radar imaging by NASA’s Cassini spacecraft there’s a lot we just don’t know about them. But one thing some researchers have managed to figure out using simulated Titan environments in the lab is that these lakes may sometimes fizz with bubbles of nitrogen—potentially explaining some of the mysteries of Cassini’s observations.
“Thanks to this work on nitrogen’s solubility, we’re now confident that bubbles could indeed form in the seas, and in fact may be more abundant than we’d expected,” said Jason Hofgartner of JPL, who serves as a co-investigator on Cassini’s radar team and was a co-author of the study.
Read the news straight from NASA here: Experiments Show Titan Lakes May Fizz with Nitrogen
By now you probably know about the lakes of liquid hydrocarbons on Titan. Thanks to Cassini, we know that Saturn’s largest moon is the one other place in the solar system where liquid can be found in stable amounts on the surface, except that it’s not water like we have here on Earth, but rather liquid methane. (Thank you for not smoking!) Now, radar measurements by Cassini show that Titan’s lakes are nearly all found in one 600 x 1100-mile region around its north pole — a true “land o’lakes!”
The animation above, made up of colorized radar data acquired over the past 9 years that the spacecraft has been in orbit around Saturn, takes us on a flyover tour of Titan’s northern lakes region. Fasten your seat belts!
Saturn’s largest moon Titan has often been likened to a primordial Earth, with its thick atmosphere, changing weather patterns, and — most intriguing of all — vast amounts of liquid on its surface in the form of lakes, streams, and rivers. One big difference though: nearly ten times farther from the Sun than we are, temperatures on Titan are a chilly 290 degrees below zero (F) and so the liquid isn’t water, it’s methane… what’s called natural gas on Earth.
Still, methane does a good job replacing water in Titan’s own version of a hydrologic cycle. Methane rain falls to fill streams, carving gullies and canyons through the frozen landscape (where water is harder than rock) and eventually filling methane lakes and seas — some as large as our Great Lakes! Cassini has found evidence of Titan’s lakes in both repeated radar scans as well as visible-light images… but what hasn’t been found yet, strangely enough, are waves on the surfaces of these lakes. If they are indeed liquid methane, and Titan has weather capable of creating rain and sculpting dunes, then why are these enormous lakes so incredibly flat?
As seasons slowly change, Cassini will find out the answer.
New research on Jupiter’s ice-covered moon Europa indicates the presence of a subsurface lake buried beneath frozen mounds of huge jumbled chunks of ice. While it has long been believed that Europa’s ice lies atop a deep underground ocean, these new findings support the possibility of large pockets of liquid water being much closer to the moon’s surface — as well as energy from the Sun — and ultimately boosting the possibility that Europa could harbor life.
“Now we see evidence that it’s a thick ice shell that can mix vigorously, and new evidence for giant shallow lakes. That could make Europa and its ocean more habitable.”
– Britney Schmidt, Institute for Geophysics, University of Texas at Austin