beneath the ice-covered surface of Saturn's moon, Enceladus hides a vast ocean that can harbor extraterrestrial life. An ocean about 1 billion years old, the perfect age to harbor life, according to NASA researcher Marc Neveu.
Neveu and his colleagues used simulations to calculate the age of Enceladus using data collected by the Cassini spacecraft, which orbited Saturn for 13 years. The scientist and his team published their findings last April in the journal Nature Astronomy.
One of the main discoveries of Cassini was that Enceladus had an ocean full of hydrothermal vents. "It's very surprising to see an ocean today," Neveu told Live Science. "It's a very small moon, and in general, you expect little things not to be very active[mas sim] like a dead block of rock and ice."
The tiny moon does not have just one ocean, "…[outra] there is size of habitability … time," Neveu said.
If the ocean is very new – for example, only a few million years ago – there would probably not be enough time to mix these ingredients to create life, he said. Besides, there is not enough time for little sparks of life to spread enough that Earthlings can detect them.
On the other hand, if the ocean is very old, it is as if the "battery" of the planet is ending; the chemical reactions needed to sustain life can stop, Neveu said.
In this world, the elements that needed to dissolve would have dissolved, all the minerals needed to form would have formed, he said. The moon would then have reached a balance, meaning that the reactions to sustain life would not happen.
This means that the ocean of Enceladus may be the perfect age to harbor life.
Neveau and his team estimated the age of the ocean with a little kick. They did about 50 simulations, connecting various parameters based on the measurements Cassini took, such as the details of Saturn's moons orbit, the radioactivity of the rocks in Enceladus, and their own assumptions about the age of the moon and how it formed .
The simulation that best reproduced the current conditions of the icy moon estimated that the ocean was 1 billion years old. However, Neveu cautions that this age estimate was based on a single simulation. And although it corresponds to many of the conditions seen in Enceladus, it does not correspond to all of them.
"For example, if you took advantage of today, the ocean would be refrozen in that simulation, which is not what we're seeing." So the age of the ocean should be taken with a grain of salt, Neveu said.
Neveu and his team are working to make their simulation run faster. The hope is that with faster runtime and slightly improved models, they can more accurately date Enceladus' oceans. "We want to know this before we go back to looking for life," he said.
