When NASA’s Cassini probe visited Saturn’s sixth moon Enceladus in 2005, its observations led to a surprising discovery.
The 310-mile-diameter icy moon is not just another cold rock. Active – a real chemistry laboratory in space. A salty ocean churning under its cold crust. Holes in the ice condensing along the moon’s south pole are pumping powerful chemical fumes hundreds of kilometers into space.
All this active chemistry has elevated Enceladus to the top of the list of planets and moons that may have the right conditions for simple life forms in the solar system. But some key ingredients for microbial evolution seemed to be missing. The most important of these was hydrogen cyanide, sometimes called prussic acid, which is highly flammable, highly toxic but also super useful as an ingredient in many industrial chemicals and pharmaceuticals here on Earth.
More than 15 years after Cassini reached Enceladus, a team of researchers from Caltech and Harvard took a closer look at the tons of data the probe had collected during its 10-year mission and concluded that the initial readings were wrong. Enceladus make Astrobiologists Jonah Peter and Kevin Hand and planetary scientists Tom Nordheim claimed to have hydrogen cyanide. And that bodes well for hopes that the icy moon is home to alien life.
Is This Icy Moon Our Best Chance to Find Alien Life?
“Our results indicate the existence of a rich, chemically diverse environment that could support complex organic synthesis and possibly even the origin of life,” wrote Peter, Hand and Nordheim in a new study published online. January 12. All three scientists are affiliated with Caltech and NASA’s Jet Propulsion Laboratory. Peter also works for Harvard.
The team’s findings may force scientists to prioritize Enceladus more as they intensify their search for alien life. It may even become a higher priority than Jupiter’s moon Europa, which has much in common with Mars, Venus, and even Enceladus and is a favorite target of alien hunters.
This does not mean that first contact is imminent. Right now, what scientists hope to confirm about Enceladus is clear. conditions for life, somewhere under the cold crust of the moon. Checking all these chemical and environmental boxes could justify new missions to the moon in the coming years.
And it is these probes that can find very simple life forms: bacteria or other microbes. “I find the possibility of microbial subterranean life high on Enceladus or Europa,” Avi Loeb, a Harvard physicist who was not involved in Cassini’s reanalysis, told The Daily Beast.
Loeb warned: “I doubt there are dead fish lying on the icy surface.”
Biologists generally agree that simple organisms as we understand them need certain combinations of certain components to thrive: carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus, for starters. And there must be sufficient volatility in the surrounding environment, mainly the elements that move and agitate, to provide energy for chemical reactions that mix, match and re-mix these elements until they produce something that can eat, metabolize, discharge, breathe, move. growth, reproduction, and response to external stimuli. This life.
There are important middle steps in this evolutionary process. And hydrogen cyanide (a compound of hydrogen, carbon, and ammonia with the chemical formula HCN) makes one of these steps possible. “With HCN, you can create biochemically important molecules like amino acids,” Dirk Schulze-Makuch, an astronomer at the Technical University of Berlin, told The Daily Beast. Amino acids, in turn, can form the proteins that living cells need to function and reproduce.
By examining data from Cassini’s first pass through Enceladus’ southern clouds, scientists quickly found signs of carbon, hydrogen, nitrogen, oxygen, and sulfur. Feathers showed variability; therefore, among the essential components of life, the Moon was only missing a few things for evolution. Hydrogen cyanide or something like that was one of them.