What is creating all that energy beneath the ice on Saturn's moon Enceladus?

Illustration for article titled What is creating all that energy beneath the ice on Saturn's moon Enceladus?

Enceladus is home to one of the solar system's most incredible hotspots, churning out 15.8 gigawatts of power. It's even more proof that there's a liquid ocean hiding beneath the ice...but scientists have no clue what's creating all that heat.


The heat created in Enceladus's southern polar region is 2.6 times that created by all the hot springs and geysers at Yellowstone National Park. Even more amazingly, it's a whopping ten times the amount of power scientists predicted what be observed when the Cassini probe took a look at the moon. Saturn's sixth largest satellite, Enceladus certainly seems to have an active interior near its south pole, centered on four huge, parallel fissures known as "the tiger stripes."

These stripes are all about eighty miles long and 1.2 miles wide. They're responsible for ejecting plumes of water vapor and various other particles into space. When these ice geysers were first discovered back in 2005, scientists estimated they could create about 1.1 gigawatts, plus another 0.3 gigawatts thanks to the moon's natural radioactivity.

So what's creating all this power in the first place? We do at least understand the basic mechanism - Enceladus interacts gravitationally with another of Saturn's moons, Dione. These tidal forces churns up the interior and is responsible for creating the intense heat, which in turn accounts for all the power.

That isn't necessarily a constant relationship, and it's possible that Enceladus's gravitational relationship with Dione and Saturn becomes more and less extreme over time. When first observed in 2005, it was going through a more moderate or even a quiet spell, whereas now the tidal forces are particularly fierce.

Either way, all this heat makes the presence of a liquid water ocean beneath the icy crust that much more likely. Since life has been able to take hold in pretty much every place water exists on Earth, astrobiologists have looked to any potentially watery environment as a great place to look for life as we know it. Even better, the plumes coming out of Enceladus's ice geysers do appear to include organic chemicals, which are the most basic building blocks of what can eventually become life.

So no, it's definitely not proof of life on Enceladus - or even proof of a liquid ocean there, if it comes to that - but these findings manage to be both genuinely baffling and hugely encouraging, which is pretty much the best one-two punch science can provide.


Via Space.com. Image via Daily Galaxy.


Simon DelMonte

15.8 gigawatts? 15.8 gigawatts?