New Organic Compounds Found in Enceladus Ice Grains



In this image captured by NASA’s Cassini spacecraft in 2007, the plumes of Enceladus are clearly visible. The moon is nearly in front of the Sun from Cassini’s viewpoint.

Credits: NASA/JPL-Caltech

Full image and caption

New kinds of organic compounds, the ingredients of amino acids, have been detected in the plumes bursting from Saturn’s moon Enceladus. The findings are the result of the ongoing deep dive into data from NASA’s Cassini mission. 

Powerful hydrothermal vents eject material from Enceladus’ core, which mixes with water from the moon’s massive subsurface ocean before it is released into space as water vapor and ice grains. The newly discovered molecules, condensed onto the ice grains, were determined to be nitrogen- and oxygen-bearing compounds.

On Earth, similar compounds are part of chemical reactions that produce amino acids, the building blocks of life. Hydrothermal vents on the ocean floor provide the energy that fuels the reactions. Scientists believe Enceladus’ hydrothermal vents may operate in the same way, supplying energy that leads to the production of amino acids.


This illustration shows the process of organic compounds making their way onto ice grains emitted in plumes from Saturn’s moon Enceladus, where they were detected by NASA’s Cassini spacecraft.

Credits: NASA/JPL-Caltech

Full image and caption

“If the conditions are right, these molecules coming from the deep ocean of Enceladus could be on the same reaction pathway as we see here on Earth. We don’t yet know if amino acids are needed for life beyond Earth, but finding the molecules that form amino acids is an important piece of the puzzle,” said Nozair Khawaja, who led the research team of the Free University of Berlin. His findings were published Oct. 2 in the Monthly Notices of the Royal Astronomical Society.

Although the Cassini mission ended in September 2017, the data it provided will be mined for decades. Khawaja’s team used data from the spacecraft’s Cosmic Dust Analyzer, or CDA, which detected ice grains emitted from Enceladus into Saturn’s E ring.

The scientists used the CDA’s mass spectrometer measurements to determine the composition of organic material in the grains.

The identified organics first dissolved in the ocean of Enceladus, then evaporated from the water surface before condensing and freezing onto ice grains inside the fractures in the moon’s crust, scientists found. Blown into space with the rising plume emitted through those fractures, the ice grains were then analyzed by Cassini’s CDA.

The new findings complement the team’s discovery last year of large, insoluble complex organic molecules believed to float on the surface of Enceladus’ ocean. The team went deeper with this recent work to find the ingredients, dissolved in the ocean, that are needed for the hydrothermal processes that would spur amino acid formation.

“Here we are finding smaller and soluble organic building blocks — potential precursors for amino acids and other ingredients required for life on Earth,” said co-author Jon Hillier.

“This work shows that Enceladus’ ocean has reactive building blocks in abundance, and it’s another green light in the investigation of the habitability of Enceladus,” added co-author Frank Postberg.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency (ESA) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the U.S. and several European countries.

More information about Cassini can be found here:

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October 3, 2019 2:51 am

Interesting stuff. And to think that before the Voyager missions to Jupiter, Saturn, Neptune and Uranus in the 1980’s most of us thought that their moons would be like our own Moon…just dead (and maybe dead boring to some)!

Ron Long
October 3, 2019 3:17 am

Looks like we have about 3 billion years, or so, before the evolution of amino acid to pond scum to invertebrate to vertebrate to people leads to UFOs traveling to our earth. Wait a minute, I watched Nancy Pelosi say one of Trump’s crimes was to not deal with climate change! They’re already here! Please add a permanent sarc tag, thank you.

Reply to  Ron Long
October 3, 2019 12:49 pm

Does that mean that Extra Terrestrials observing that Earth is currently creating similar compounds from geothermal vents should also conclude that 3 billion more years need to pass before advanced intelligent life forms occupy it surface?

Enceladus and Europa may already have advanced life forms, just not space fairing yet.

October 3, 2019 3:21 am

May be Gold is right with the idea of the deep hot biosphere.

Reply to  Krishna Gans
October 3, 2019 4:44 am

Gold was right about “the deep, hot biosphere”…

The deep, hot biosphere: Twenty-five years of retrospection

He was just wrong about mantle-sourced hydrocarbons.

Reply to  David Middleton
October 3, 2019 5:39 am

Many thanks for the very interesting link !!

October 3, 2019 3:31 am

Very interesting, and I am glad that NASA is again involved in Space matters rather than assisting the Greens in their quest to destroy the civilisation which has developed on Planet Earth.


Reply to  Michael
October 3, 2019 6:15 am

Hopefully, they’re using the data in pristine form and are not adjusting it first.

Patrick MJD
October 3, 2019 3:33 am

What? You mean the “science” isn’t settled?

Benjamin W
October 3, 2019 3:55 am

“This work shows that Enceladus’ ocean has reactive building blocks in abundance, and it’s another green light in the investigation of the habitability of Enceladus,” added co-author Frank Postberg

This is like finding Taconite and saying that you found the building blocks for the Empire State Building. Technically correct, but omitting just what it takes to get Taconite into the Empire State Building.

I sometimes think these people are thinking with a 19th century understanding of life. (Or just overstating what they’ve found.) Life is a LOT more than tossing chemicals in a jar and shaking it. It needs programing, information. The DNA programing for the simplest life we know of still takes up just over half a megabyte of space. Change a few base pairs and it stops working.

People have done the math. There’s not enough monkeys or time in the visible universe to bang out the DNA computer code at random.

Might we find iife there? Sure. We also might find a replica of the Titanic. What you MIGHT find doesn’t interest me. Talk is cheap. Show me what you DID find.

Reply to  Benjamin W
October 3, 2019 4:51 am

A sloppy reading would indicate that they found amino acids. They did not. AFAICT they found the precursors to amino acids, nitrogen and oxygen-bearing compounds to be specific. That, by itself, is interesting but does not indicate the presence of life as we know it.

M Courtney
Reply to  Benjamin W
October 3, 2019 4:56 am

People have done the math. There’s not enough monkeys or time in the visible universe to bang out the DNA computer code at random.

True. But it’s not random.
Non-working arrangements are weeded out by a process called death.

Reply to  M Courtney
October 3, 2019 10:47 am

And yet…we still have those pesky “non-working arrangements” (a.k.a. Climate Models) still managing to out live their usefulness.


michael hart
Reply to  M Courtney
October 3, 2019 6:53 pm

Correct, M Courtney. None of the chemical reactions involved in the synthesis of nucleotides and their oligomerization to RNA and DNA molecules are particularly surprising in the “chemical soup” model. The beauty arises when these molecules can then catalyze the auto-synthesis of a duplicate molecule by the self recognition process of the hydrogen bonding between the nucleobases: This leads to self-replication and thus exponential growth when the conditions of the soup are favorable. A key mark of life, yet still nothing astoundingly improbable.

Selective evolution then works its magic. Arnold, Smith, and Winter were awarded the Nobel Prize only in 2018 for their work on directed evolution in the test-tube. To synthetic experimentalists and modelers alike, the biochemical power of this technique has been shown to be staggering. I turn green with envy when I read or think about it. I often wish I was starting my PhD studies again so I could make use of it.

John Tillman
Reply to  michael hart
October 4, 2019 1:07 pm

Yup. Short chains, ie oligomers, of RNA self-assemble under a variety of conditions. The trick is getting them to keep growing longer, ie polymerize, aided by abiotic enzymes.

RNA serves both as an enzyme and as a library of genetic info. Surprisingly short chains of RNA show catalytic function, but they need to be long enough to bend into useful shapes.

In the RNA-DNA-protein world, of course, DNA has taken over most of the info storage function and proteins the enzymatic roles.

The ribose sugar in DNA has one less oxygen atom than the sugar in RNA, which lack allows it to form a double helix, making it a more stable repository of genetic information.

Starting from one gene (protein-coding sequence) in the first protocell to ~3700 genes in a modern cyanobacterium would take fewer than 12 whole genome duplications in 500 million years or less of bacterial evolution. Call it one duplication per 40 million years. Probably was a lot more frequent than that early on.

Humans are presently estimated to have 19,000 genes, but could still be fewer.

The last unicellular ancestor of animals was a choanoflagellate, or collared cell. The genome of a modern choanoflagellate species, Monosiga brevicollis, contains approximately 9200 intron-rich genes, including a number that encode cell adhesion and signalling protein domains that are otherwise restricted to metazoans (animals).

So it’s theoretically only one doubling from unicells to multicellular animals, over hundreds of millions of years. In reality, there have been more than that, to include at least two in the vertebrate lineage.

John Tillman
Reply to  michael hart
October 4, 2019 1:20 pm

Amoebas are fairly closely related to choanoflagellates, but the number of genes doesn’t scale directly with genome size as measured by base pair number.

Thus, at least in the animal kingdom, the relationship between genome size and evolutionary complexity is not linear. One of the largest genomes belongs to a very small creature, Amoeba dubia. This protozoan’s DNA contains 670 billion base pairs. The genome of a relative, Amoeba proteus, has a mere 290 billion base pairs, which is still 100 times larger than the human genome.

Reply to  Benjamin W
October 3, 2019 12:55 pm

“I sometimes think these people are thinking with a 19th century understanding of life.”
Don’t forget a little introspection on that.

Your time calculations are based upon your preconditioned thinking on how fast it takes to write code, and our current methods of constructing it.
If anybody did it, it certainly wasn’t humans.

John Tillman
Reply to  Rocketscientist
October 4, 2019 2:45 pm

Creationists lie with bogus statistics, totally divorced from how biology actually works, to mislead audiences not able to detect their blatant falsehoods. Much as gullible, impressionable, sophomoric, austistic St. Greta of Stockholm has been used.

John Tillman
Reply to  Benjamin W
October 3, 2019 3:58 pm

The first protocells didn’t have 19,000 genes, ie protein-coding sequences, as do humans. They probably had just one.

The supposed math is worse than worthless and meaningless, because that’s not how biology works. You don’t start from an assemblage of atoms and molecules, then try to make RNA or DNA, as with monkeys and typewriters.

You start with the complex chemical compound monomer precursors of RNA, which self-assemble naturally, via organic and physical chemistry. The most important nucleobase, adenine, is produced simply by warming HCN, a compound ubiquitous in the universe, in a solution of ammonia, another simple compound, similarly abundant.

Amino acids, sugars, fatty acids, nucleobases and phosphate groups, the building blocks of the polymers of life, all arrive on Earth on meteorites. They come equally in left- and right-handed forms, but life prefers left-handed, at least on this planet.

The trick to move from chemical evolution to the development of life is polymerization. The needed monomers abounded on early Earth. Concentrating them and linking them in longer chains gave rise to the first organism.

Simple experiments have already shown how cell membranes evolved. Harder chemistry has now also shown how all the nucleobases can be made abiotically, although we already knew that happens, thanks to the meteorites.

Whether moons of the gas giants harbor life or not, who can say. But the ingredients appear to be there, and liquid water, plus tidal energy sources, so it’s at least possible.

Geoff Sherrington
October 3, 2019 4:54 am

In years to come it will be fascinating to follow the enantiomer story, to see if Nature made all dextro or all laevo or (?equal) numbers of each dominating as each host planet/moon yields its organic carbon chemicals.
Geoff S

Reply to  Geoff Sherrington
October 3, 2019 1:47 pm

Geoff Sherrington
October 3, 2019 at 4:54 am

Yes, interesting point. I wonder if any of the space probes to comets (eg Rosetta) had instruments that could detect handiness of those organics. I suspect not but it would be a nice thing to do for future missions…especially if we can catch up to some of the visitors from other solar systems that we are now seeing.

Thomas Homer
October 3, 2019 6:25 am

Pretty slick to discuss: “New kinds of organic compounds”; without mentioning Carbon.

[ Organic compound, any of a large class of chemical compounds in which one or more atoms of carbon are covalently linked to atoms of other elements, most commonly hydrogen, oxygen, or nitrogen. ]

Reply to  Thomas Homer
October 3, 2019 9:06 am
Thomas Homer
Reply to  David Middleton
October 3, 2019 11:49 am

Thank you

Pop Piasa
Reply to  David Middleton
October 3, 2019 5:51 pm

David, are these VOCs they’re talking about condensing and freezing? AOC sez VOCs are not PC.

October 3, 2019 9:07 am

Has anyone postulated whether the spontaneous creation of life is the result of an endo- or exothermic reaction? I would assume endothermic, so any search for life would require looking in areas warmer than the surfaces of outer moons. Warmth may easily exist at deeper levels, but if so, life would be more difficult to find.

John Tillman
Reply to  jtom
October 3, 2019 4:01 pm

The hypothesis isn’t on the surface of moons, but in their subglacial oceans or under a thick atmosphere, in Titan’s case, but also a probable water sea there too, under the hard ice crust.

Life might be inevitable under the right conditions, where it solves certain physical energetic problems.

Steve Z
October 3, 2019 2:31 pm

Even if Enceladus has a sub-surface ocean of water with amino acids, it would be unlikely that Earth-like life forms could survive there. Marine life on Earth is based on phytoplankton, which use energy from sunlight to make food. A sub-surface ocean would not receive sunlight, and the surface of Enceladus is much too cold to have liquid water (and receives too little sunlight).

John Tillman
Reply to  Steve Z
October 3, 2019 3:47 pm

Earth had life for perhaps 500 million years before the evolution of photosynthesis using CO2 and water. The first cyanobacteria evolved from chemosynthetic ancestors.

Reply to  Steve Z
October 3, 2019 4:36 pm

There are lots of archaebacteria on Earth that are not dependent on sunlight, including chemotrophs and lithotrophs, and some of these live in the ocean–generally very deep ocean, far from sunlight. Not your typical marine life, I guess, but marine nonetheless.

John Tillman
Reply to  mcswell
October 3, 2019 4:53 pm

The probable ancestor of us eukaryotes was such an archaean, of the Asgard group:–66264

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