The exploration of the outer Solar System has revealed a plethora of amazing worlds, the likes of which were little known or even unheard of just a decade ago. Among the most remarkable and tantalizing discoveries are the “ocean moons” such as Europa and Enceladus, which have oceans or seas of liquid water beneath their icy surfaces. Other moons like Titan, Ganymede, and Callisto may also have them, and even some asteroids. Titan also has seas and lakes of liquid methane/ethane on its surface. With all that water, these small worlds have become a primary focus in the search for possible life elsewhere in the Solar System. Now, a new NASA budget proposal wants to take that a step further and fund new missions to these watery moons.
The search for life elsewhere has long focused on what we are most familiar with on Earth – in other words, “life as we know it,” or organisms which are carbon-based and require water to survive. However, a growing number of scientists are now thinking that alternative forms of life are possible, ones which have never been seen on Earth, but could flourish in other types of alien environments. A new study from Cornell University addresses this very question, demonstrating a form of microscopic life which would be possible on Saturn’s largest moon Titan.
Who wouldn’t want to go explore an alien sea? It seems that NASA would certainly like to, and the agency has unveiled a new submarine design to hopefully do just that one day. The submarine would be sent to Saturn’s largest moon, Titan, to dive into one of the large liquid methane seas on the moon’s frigid surface; such a mission idea may sound like science fiction, but it’s not, and would be the first ever to explore a sea on another world which is both Earth-like in some ways, yet utterly alien in others.
Saturn’s largest moon Titan is a fascinating world, uniquely alien yet eerily Earth-like in many ways, with its rain, rivers, lakes, seas, and massive sand dunes. But in this extremely cold environment, it is liquid methane and ethane which act as “water,” mimicking the hydrological cycle on Earth. Also, due to the perpetual and global hazy cloud cover, the only way to see these features from orbit is by using radar, which is what the Cassini spacecraft has done on a regular basis for quite a few years now. As good as they are, though, the radar images contain electronic noise, which reduces sharpness and clarity. But now a new technique is letting planetary scientists see Titan’s surface more clearly than ever before.
The Cassini spacecraft has taken thousands of images of Saturn and its moons, and this one is another beauty. Titan, Saturn’s largest moon, and the one with the methane rain, rivers and lakes, floats in space out beyond Saturn’s rings.
This is a beautiful montage showing sunlight reflecting off lakes on two different worlds. A water lake (of course) on Earth and a methane lake on Saturn’s moon Titan. While the composition is quite different, the hydrological and methanological processes are remarkably similar, with rain, rivers, lakes and seas. Familiar but alien at the same time… Thanks to Planetary Landscapes for use of this image!