121 moons discovered that may harbor alien life

UCR researchers have identified 121 giant planets that may have habitable moons

This is an artist’s illustration of a potentially habitable exomoon orbiting a giant planet in a distant solar system.
CREDIT NASA GSFC: Jay Friedlander and Britt Griswold

RIVERSIDE, Calif.– We’ve all heard about the search for life on other planets, but what about looking on other moons?

In a paper published Wednesday (June 13) in The Astrophysical Journal, researchers at the University of California, Riverside and the University of Southern Queensland have identified more than 100 giant planets that potentially host moons capable of supporting life. Their work will guide the design of future telescopes that can detect these potential moons and look for tell-tale signs of life, called biosignatures, in their atmospheres.

Since the 2009 launch of NASA’s Kepler telescope, scientists have identified thousands of planets outside our solar system, which are called exoplanets. A primary goal of the Kepler mission is to identify planets that are in the habitable zones of their stars, meaning it’s neither too hot nor too cold for liquid water — and potentially life — to exist.

Terrestrial (rocky) planets are prime targets in the quest to find life because some of them might be geologically and atmospherically similar to Earth. Another place to look is the many gas giants identified during the Kepler mission. While not a candidate for life themselves, Jupiter-like planets in the habitable zone may harbor rocky moons, called exomoons, that could sustain life.

“There are currently 175 known moons orbiting the eight planets in our solar system. While most of these moons orbit Saturn and Jupiter, which are outside the Sun’s habitable zone, that may not be the case in other solar systems,” said Stephen Kane, an associate professor of planetary astrophysics and a member of the UCR’s Alternative Earths Astrobiology Center. “Including rocky exomoons in our search for life in space will greatly expand the places we can look.”

The researchers identified 121 giant planets that have orbits within the habitable zones of their stars. At more than three times the radii of the Earth, these gaseous planets are less common than terrestrial planets, but each is expected to host several large moons.

Scientists have speculated that exomoons might provide a favorable environment for life, perhaps even better than Earth. That’s because they receive energy not only from their star, but also from radiation reflected from their planet. Until now, no exomoons have been confirmed.

“Now that we have created a database of the known giant planets in the habitable zone of their star, observations of the best candidates for hosting potential exomoons will be made to help refine the expected exomoon properties. Our follow-up studies will help inform future telescope design so that we can detect these moons, study their properties, and look for signs of life,” said Michelle Hill, an undergraduate student at the University of Southern Queensland who is working with Kane and will join UCR’s graduate program in the fall.


The title of the paper is “Exploring Kepler Giant Planets in the Habitable Zone.”

55 thoughts on “121 moons discovered that may harbor alien life

  1. So it is a project to develop a telescope to actually find such moons? Is the Webb telescope suitable, or would it require another generation of telescopes?

    • They still can’t see planets, and now they are talking about trying to see moons around those planets?

      The two techniques that I know of for detecting planets are watching for a wobble in the position of the star, and watching for the stars light level to dim as a planet crosses in front of it.

      I don’t see how either of those techniques can be used to detect a moon around a planet.

      • Just my sense, but I suspect the odds of a seeing a planet cross in front of its star (basically an eclipse with the Earth most likely out of the system’s ecliptic) would be a one-in-thousands event. We need an extremely long baseline telescope, first with laser/clock linked apertures at opposite geosynchronous orbits, then with apertures at the Trojan points of Earth’s orbit about the sun.

  2. It’s premature to discuss whether these hypothetical moons might be suitable places where life MIGHT exist, to say nothing about what sort of life it might be. Life there, if any, will be SO alien that we might not be able to recognize it as “life”.

    • Someone selling advertising space ‘content’, with rank sci-fi speculation, passed off as ‘findings’, for about the eleventy-seventh billionth time … for assured gullible clicks.

  3. Jupiter’s moons are a tough place for living things anywhere that is not well below ground on account of the radiation levels. Jupiter has a stronger magnetosphere than Earth and Jupiter’s large moons are exposed to the resulting bombardment of charged particles.

    Would Earth’s magnetic field be strong enough to fend off the radiation were Earth orbiting Jupiter?

    • Saturn has a more benign radiation environment than Jupiter.

      I guess the size of the giant planet matters. The bigger they are, the more harsh the environment around them.

    • Earth’s periodic magnetic reversals, with near zero, chaotic field lines at times, would be a major problem.

      • It appears that the earth magnetic field doesn’t go to zero during a reversal.
        Rather patches of reverse magnetic fields begin to show up and over time increase in number and size.

    • I would assume that if Jupiter were closer to the sun, the intensity of it’s radiation fields would be even higher.

    • “Jupiter’s moons are a tough place for living things anywhere that is not well below ground on account of the radiation levels. ”

      You are basing that assumption on our knowledge of life as we know it. We actually only have very little knowledge of life (other than how we know it – how else could it be?). The only thing we do know is that life is very, very tough and adaptable to boot. So the probability is that it does exist but that, as others have said, we may not recognize it as such.

  4. It is like Crevo debates never happen. Creationists often argue the mathematical impossibility of proteins forming even under ideal conditions; even in the highly controlled atmosphere of the laboratory. Furthermore the Warmunists, who are not Creationists keep reminding us that a 1C degree change over a century of time will End Life As We Know It because adaptation apparently doesn’t really happen.

    So the Warmunists demand a comprehensive and extremely tight set of environmental conditions, a set of conditions that can be permanently erased on Earth unless global Statists dictate our lifestyles and nano-manage our choices (like food choices and thermostat settings).

    But with a telescope and a computer model they can boast that better-than-Earth conditions exist all over the universe and the mathematical impossibilities are magically mathematical certainties.

    We know next to nothing about our own climate, oceans and anything deeper than what a drill bit can achieve but are ecstatic over a computer model’s programmed result.

    Yet another fine example of Gell-Mann Amnesia.


    • The exoplanets don’t have humans so of course they are possibly better than Earth. If only humans would have the moral decency to off themselves, Earth could heal. /sarc

    • I also smiled when I read the better-than-earth comment. Lots of these people studying hypothetical life in hypothetical places seem to have given up studying real life, possibly because it’s a bit too hard for them.

      …And energy itself is not really the prerequisite for life, but energy gradients. Life makes use of energy gradients to do (chemical) work, just as a heat engine makes use of energy gradients. The heat engine cannot work if it only has a hot ‘source’. It must also have a cold ‘sink’. Work is extracted as energy moves down the gradient from hot to cold. Thermodynamically, life works in exactly the same way.

  5. I guess we are lucky that they are wasting their time and our money on this instead of becoming, God forbid, “climate scientists”.

  6. The existence of life forms that are totally alien to us, in hydrothermal vents on the ocean floor, has only been known to us for 41 years. On our own planet!

    Hydrothermal vents may even be the places where life actually started on earth. If there are planets and moons with oceans and volcanoes, these are the likeliest places to look for life, but it might be hard to detect from a distance.

    An unmanned mission to Europa, the best candidate in the solar system for hydrothermal vents, is well within our capabilities now. Instead of a rover, it would need a submersible.

    • Hydrothermal vent life isn’t alien to us. It’s still based upon the same genetic and metabolic biochemistry as all life on Earth.

      • The laws of physics are the same on distant moons, or planets. The basic building blocks and patterns of what we call life in the physical world are therefore not likely to be radically unrecognizable to us there, any more than here. Different and diverse and strange? Sure.
        Extant life within the framework of physical law of which we are as yet unaware? Why not?

        Individual units of performing consciousness which exist beyond our defined concepts of life, in a non- physical world?

        • Physics is the same but the chemical environment is different. Chemistry is very dependent upon temperature and pressure. When water isn’t liquid, then some other compound will need to provide the solvent. If hydro-carbon compounds can’t properly maintain long chains then some other chain forming elements may be the basis.

          Also, a lot of how life on Earth is composed depends on the initial formation of the building blocks and their use. There may be other reproduction mechanisms than the DNA-protein mechanism.

    • We’re a long way from even routinely (and affordably) visiting and surveying our own 60,000 km of MOR for life, but we suppose we can do it on another globe, which is frozen, somewhere out there, and mount a protracted systematic survey to find and identify life, and then get that survey data relayed back to humans?

      Don’t hold your breath waiting for that.

      • We will eventually study the moons in our own solar system enough to find life, if it is there. What we find here will apply to the moons of other solar systems.

        We do need a FTL (Faster Than Light) drive. Wouldn’t you love to be able to just zip over to a new solar system and check it out. Maybe someday. 🙂

    • When you figure out how to send a probe 628 million kilometers into space that can drill through 100 km of hard ice, and lower a probe… let me know. Otherwise hydrothermal vents on an Europa ocean floor is just speculation.
      There may well be water sprays into space above Europa from cracks in the ice layers. And future missions to Europa are worthy endeavors, with fast flybys, but Europa has a heavy radiation environment on its near surface, even for robotic spacecraft it is hazardous.

      And Europa does have a very thin Oxygen atmosphere, due to solar UV dissociation of water into H and O, where the H rapidly escapes to space. Nothing to do with life.

      • I guess we could drop a blob of plutonium to create a China syndrome drill, chase it with CO2 and then place a super high pressure probe which we chase with liquid methane. The blob drops through the ice and the radiation kills the Europans but the probe can take samples and see what they used to be like.

  7. And they may far more likely are just high-energy radiation-blasted, obliquity wandering sterile rocks.

  8. might provide a favorable environment for life, perhaps even better than Earth. That’s because they receive energy not only from their star, but also from radiation reflected from their planet.

    Uhm… did they just say warmer is better?

  9. None of these planets will have life. Almost all of the planets found are around Red Dwarfs, where the “habitable zone” is so close that you’re just outside the corona. Red Dwarfs are notoriously unstable, and emit huge flares, thus sterilizing any planets in the habitable zone. Plenty of other reasons what RD stars are no good – planets are tidally locked – one side frying while the other frozen. They emit almost no visible light. etc etc. This is more junk science. Just a bunch of con-artists trying to fool the public into funding their junk science research.

    • Kepler is not junk science unless you think all of astronomy is junk science.

      Speculating on what Kepler has found might be junk science or just speculation.

      We need a bigger Kepler in orbit to replace this one.

      There are also some really big telescopes (space-based and ground-based) planned for the future. I’m eager to see them come on line. We have a long way to go in understanding the Universe we live in.

  10. When I read “may” in this gibberish I turn off.

    Why can’t they say “we have no idea”. Makes one want to vomit.

    Where have all of the real scientists gone..

    • Mark, all science starts with observations and speculation based on that observation. A good “What If” helps propel science. Don’t disrespect imagination. Einstein swore by it.

  11. Headline: “121 moons discovered that may harbor alien life”
    From the article: “Until now, no exomoons have been confirmed.”


  12. “121 moons discovered that may harbor alien life”

    That’s grossly misleading. It says they have discovered planets that MAY have moons…

  13. The title says that 121 one moons that may harbor alien life.

    The article says that 121 planets have been found in the habitable zone, and IF these planets had moons, some of those moons might be habitable.

    VERY, VERY big difference.

    The title of this article is completely wrong and misleading.

    • There’s also the “IF these are planets” aspect too.

      Right now, they have anomalies that are consistent with exoplanets. Until they can put a probe into one of these star systems, they haven’t actually discovered anything.

    • Another problem is even though the “planets” are in the habitable zone currently, we don’t know how long they have been in the habitable zone.

      According to current theory gas giants will spiral in towards the sun until the crash into it, unless something stops them.
      In our solar system it was a fortuitous placement of Saturn that stopped this inward migration.

  14. Just because the ingredients exist in no real scientific way concludes the existence of life, and yet it is implied everywhere. My kitchen has all the things needed to make a cake yet no cake will ever be found unless it is made. The same is true of life unless you are still misguided by Darwinism, the magical science.

    • What is rarely acknowledged is that naturally occurring organic molecules are at least an order of magnitude simpler than the level of complexity of the molecules found within living organisms. Check out the difference between naturally occurring amino acids and the simplest proteins.

      Just because some simple organic molecules can form does not mean all the necessary ingredients of life are forming naturally. That is comparable to saying cellulose must form naturally just because H2O and CO2 occur naturally. After all, H2O and CO2 are the building blocks of cellulose.


      • Yet an experiment in California several years ago collided a container with simple compounds at meteoric speeds and generated more complex molecules because of the collision. So, nature added complexity. Could nature, over hundreds of millions of years, add enough complexity for life to start? I’d call that beautiful programming.

  15. “May have” The words that demonstrate the bankruptcy of modern “science” across the board. Science is no longer about using actual facts to verify theories. Now it’s all about who can make up the biggest and most headline worthy speculation, no matter how absurd or unlikely.

    • I agree, Jim, that “may have” has been abused, but “abuse” depends on the context. Hypothesis is a big “may have” or “what if” based on facts. The more supporting facts, the less “absurd” or “unlikely.”

      The title of this piece goes too far. 121 moons have NOT been discovered. But the thrust of the article explores the possibilities quite nicely. Such “what if’s” stimulate the thinking processes. Einstein used lots of what if’s in the development of Relativity.

  16. I truly hope humans don;t “get out among the stars” for many, many centuries.

    Humans are vermin… Can you imagine humanity out there if it’s actually teeming with other life?

    We’d be forever trying to dictate to them, convert them, steal from them (technology), impose “our way” upon them – just look how we act to each other, and we LOOK the same shape!

    Hell, imagine Islam out in the stars…. FFS!!!

    • Casey, you bring up some good concerns. Globalists and publicly-traded corporations are the worst of evil. Most common folk are nominally a good bunch. Extremism is a natural extension of self-concern and ego. Heck, just look at the climate change scam, or the anti-gun mob (creating safe spaces for lone gunmen, but not for the victims), or the Pro-Death crowd with their abortion, eugenics, euthanasia, suicide and genocide.

      I wrote about some of these concerns in my two Touch the Stars novels — Emergence (co-authored with John Dalmas) and Diaspora.

    • Or nonexistent (a tidal bulge that doesn’t move, if the moon itself is tidally locked). If there are 3 or 4 moons of similar size to Earth, the innermost might experience volcanic eruptions like those on Io.

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