The Chance for Life on Io

Jun 10, 2010 by Charles Q. Choi
High resolution close-up of Io's volcanic surface. Credit: NASA/Galileo

Jupiter’s moon Io is the most volcanically active body in the solar system. Could it also be a habitat for life?

When it comes to where might dwell in our own solar system, Jupiter's often grabs the spotlight. However, its extraordinarily volcanic sibling Io might be a possible habitat as well.

A bit larger than Earth's moon, Io is the innermost of Jupiter's large satellites and the most volcanically active body in the , with plumes of matter rising up to 186 miles (300 km) above the surface. This extreme activity is the result of Jupiter's powerful gravitational pull, which causes Io's tormented solid crust to bulge up and down 328 feet (100 meters) or more, generating intense heat in Io due to friction. Although the heat near the volcanoes can reach some 3000 degrees F (1649 degrees C), high enough to keep lava liquid, Io's surface temperature averages at about negative 202 degrees F (-130 degrees C), leading to snowfields. This means Io is a land of both fire and ice.

Io is generally considered a poor candidate for life because of all the radiation Jupiter blasts it with. In addition, no organic molecules have been detected on its surface, and it has only an extremely thin atmosphere devoid of detectable .

"Everyone right away tends to categorically exclude the possibility of life on Io," said astrobiologist Dirk Schulze-Makuch at Washington State University.

Still, conditions on Io might have made it a friendlier habitat in the distant past. If life did ever develop on Io, there is a chance it might have survived to the present day, Schulze-Makuch suggested.

"Life on the surface is all but impossible, but if you go down further into the rocks, it could be intriguing," he said. "We shouldn't categorize it as dead right away just because it's so extreme."

Computer models suggest Io formed in a region around Jupiter where water ice was plentiful. Io's heat, combined with the resulting possibility of liquid water, could have made life plausible.

“There must have been quite a lot of water on Io shortly after formation, judging from the amount of on Europa and Ganymede,” said Schulze-Makuch.

Voyager 1 took photos of Jupiter and two of its satellites (Io, left, and Europa) on Feb. 13, 1979. This photo was assembled from three black and white negatives by the Image Processing Lab at the Jet Propulsion Laboratory. Credit: NASA/JPL

Jupiter's radiation would have stripped this water from Io's surface, perhaps within 10 million years. At this point life could have retreated underground, where water might still be abundant, and geothermal activity and sulfur compounds could provide microbes with sufficient energy to survive.

Although no have been detected on the moon’s surface, that does not mean they do not exist underground, Schulze-Makuch said. Any organic compounds that once existed on the surface or that may today still emanate from the subsurface -- which probably were naturally present in this region of space during Io's formation -- would get quickly destroyed by Jupiter's radiation.

The many lava tubes thought to exist on Io could serve as an especially favorable environment for life, Schulze-Makuch suggested, by protecting organisms from radiation. The lava tubes also could provide thermal insulation, trapping moisture and providing nutrients such as sulfurous compounds. Microbes are common in lava tubes on Earth, from ice and volcano zones in Iceland to hot sand-floored tubes in Saudi Arabia, and lava tubes are the most plausible cave environment for life on Mars, he added.

The primordial soup that any life on Io might have originated from was likely based on water, but the solvent of choice for organisms there might have drastically changed later on as the moon transformed. Hydrogen sulfide is one choice, as it is reasonably abundant in Io's shallow subsurface and remains liquid from negative 123 to negative 76 degrees F (-86 to -60 degrees C), falling within the environmental conditions that would prevail there. While it is not especially efficient as a solvent for ions, it does dissolve many substances, including many organic compounds. Other possibilities include sulfur dioxide and sulfuric acid.

"I'm exploring with colleagues whether sulfur compounds could work as solvents of life," Schulze-Makuch noted.

Given the wild extremes Io can swing through as it orbits , one possible survival strategy for life in this challenging environment would be to remain dormant most of the time, only reverting back when nutrients were rich. "It'd be much easier for life to take a beating if it goes dormant regularly," Schulze-Makuch said.

Thurston Lava Tube, Hawai'i Volcanoes National Park, Big Island of Hawai'i, USA. If lava tubes exist on Jupter’s moon Io, they could serve as a protective environment for life. Credit: Michael Oswald

Although Europa and Ganymede are higher priority targets for future exploration missions, Io should not be neglected, said Schulze-Makuch. "Much insight could be gained by sending a radiation-resistant robotic probe capable of detecting the chemistry and physical state of subsurface and surface liquids on Io," he noted, perhaps as part of a larger mission to the Jovian system.

"I know the chances of life on Io are low, and even if there is some microbial life in lava tube caves in its crust, in the short term there's no way for us to get there," he added. "But let's not totally exclude Io only because it seems strange or foreign."

If a mission to Io is extraordinarily lucky enough to find life in such an unlikely environment, "then it would make life elsewhere in the galaxy seem much more likely," Schulze-Makuch said. "It would really broaden our horizons."

Schulze-Makuch detailed his ideas in the February-March issue of the Journal of Cosmology.

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Quantum_Conundrum
1 / 5 (2) Jun 10, 2010
Honestly, I find this to be ridiculously unlikely.

If the volcanism is blasting molten rock hundreds of miles into space, where it presumably falls back down eventually, it seems absurd to assume sub-surface water exists in any form other than steam.
gwrede
1 / 5 (2) Jun 10, 2010
The guys at JPL who colored the Voyager picture, didn't pay attention. The two moons ended up having the same color in the picture as their respective backgrounds, which is clearly wrong.
Skeptic_Heretic
not rated yet Jun 10, 2010
The guys at JPL who colored the Voyager picture, didn't pay attention. The two moons ended up having the same color in the picture as their respective backgrounds, which is clearly wrong.

The moon to the left looks yellow brown to me while the one on the right is smokey white. Check your monitor. Brightness might be too high.
kevinrtrs
1 / 5 (10) Jun 11, 2010
Still, conditions on Io might have made it a friendlier habitat in the distant past. If life did ever develop on Io, there is a chance it might have survived to the present day, Schulze-Makuch suggested.

This should be recognized for what it is: sheer speculation. Current conditions dictate that there is small chance for life even if it was there in the beginning - which is itself highly debatable. This is why most reasonable people dismiss that possiblity out of hand.

Just finding water on a planet does not imply life would be found.

Where would that life come from? We know now just how complex even the simplest cell is, so the spontaneous formation of life is virtually a guaranteed non-event. In fact finding water will be a detriment - surprising as that might sound - water by itself works against long chain organic compounds forming because of the simple chemistry of concentrations.
Life as we know it was created by the creator. Period.
Skeptic_Heretic
5 / 5 (4) Jun 11, 2010
This should be recognized for what it is: sheer speculation.
Wrong
Current conditions dictate that there is small chance for life even if it was there in the beginning
Again, wrong

This is why most reasonable people dismiss that possiblity out of hand.
Reasonable people don't dismiss something until all the evidence is presented. Judging pre-evidence is prejudging.

Where would that life come from? We know now just how complex even the simplest cell is, so the spontaneous formation of life is virtually a guaranteed non-event.(bunch of bullshit deleted)Life as we know it was created by the creator. Period.
We've gone through this before. When you state something that is demonstrably false, you're lying. We know that lipids form stable vesicles in aqueous solution and are permeable to monomers all of which are formed through natural processes. We know that under different thermodynamic coonditions (TBC)...

Skeptic_Heretic
5 / 5 (7) Jun 11, 2010
(cont.) We know that under different thermodynamic conditions present on the early earth that lipid vessicles would expand allowing monomer osmosis. We know that these monomers when cooled would combine forming polymers that would be unable to then exit the vesicle. Using basic chemistry and thermodynamics one can easily explain several manners of abiogenesis.

Sorry, no creator needed. Thermodynamics, basic chemistry, and a reasonable difference in undersea currents, as well as the presence of water, makes the spontaneous assembly of self replicating biology quite easily explainable.

Direct interaction Creationism (young earth or old earth) is thoroughly disproved, empirically and sensically. You have to bury your head in the sand to think otherwise. This doesn't speak to whether there is a God or not, but it certainly shows us that we're not special, nor would any sort of God be a personal one
Scott221
5 / 5 (5) Jun 11, 2010
Just had a thought; not sure if it's correct...

Assuming that Io is tidally-locked to Jupiter, then the expansion/contraction of its surface (as it orbits the planet) should always occur in precisely the same locations. Thus - in an analogy to standing waves in a microwave oven - there should be some regions of the moon that stay extremely hot, some should remain extremely cold, but some should always be in a comfortable Goldilocks-zone where solvents like liquid H2O could persist...

Might be a case for life on Io after all.
freethinking
1.2 / 5 (5) Jun 11, 2010
SH, FYI It does not go against Christian, nor Creationists belief that their COULD be life outside the Earth.

I actually hope that there is life out there... but thats another story.
Skeptic_Heretic
5 / 5 (4) Jun 11, 2010
SH, FYI It does not go against Christian, nor Creationists belief that their COULD be life outside the Earth.

I actually hope that there is life out there... but thats another story.
It goes beyond their belief that God didn't directly craft it through magical means and it contradicts the thought that God has any form of caring or personal value instilled in us over other forms of life.
trekgeek1
5 / 5 (2) Jun 11, 2010
I hate when people bring answersingenesis.com to physorg. If there is an article on this site about life outside of earth you can bet you are going to hear science and reason screaming as it is twisted and contorted to suit established conclusions.
RealScience
5 / 5 (4) Jun 11, 2010
kevinrtr - in your belief system, isn't the creator alive?
(It sure sounds like it when all those biblical folks carry on conversations with the creator).

And if it takes a living intelligent creator to create life, then who created your creator?

If you really have an open mind and want to know how the world works, this forum is a good place.
But if you 'know' that biology, geology astronomy, physics, etc. are all very wrong and the earth is really young, then please don't bother people here.

After all, we don't go onto religious forums and bother people by discussing radio-isotope dating, etc.
Gods_Doc
not rated yet Jun 13, 2010
Having a Doctorate in theology, I feel that I can contribute something to the discussion. It is unfortunae that many christians believe that the Creator only created life on earth and would limit His abilities in such a manner. Sadly, people often envision a Creator as being an old bearded man sitting on a throne. When in actuality the dynamics of physics, astronomy, and geology all provide a glimpse of what the Creator is: a powerful constructive energy that permeates the universe. This energy exists and is measurable, whether there is a conciousness to it is where faith comes into play.

This article is simply stating that from minerals in the soil, organisms could have been formed, the volcanoes and atmosphere could have breathed the "breath of life" into them.

Why must science and faith always be at odds with one another? TBC
Gods_Doc
not rated yet Jun 13, 2010
Christians who value truth must accept facts for what they are, and therefore understand and accept the wonderous mechanics by which the Creator moves through creative forces. Scientists on the other hand must also not deny the existence of a creative force unless they are able to prove that one doesn't exist. Given the size of the universe, this should prove to be a difficult task.

Scientist still can't prove how the universe was created, niether can christians. Scientists have theories (beliefs) and christians have beliefs (theories).

To my fellow christians: had it not been for scientists, we would be holding services in damp caves by torch light rather than our lighted, air conditioned churches. We have enjoyed thousands of years as an only child, we should not throw tantrums at the possability of discovering that we have a baby brother.

Thank you for your patiencs during my rant.

freethinking
1 / 5 (3) Jun 13, 2010
SH - again you show your ignorance of Christian belief. Nothing in the Bible says God didn't create life on other planets. Only people who make things up as they go (something like athiests) would have a problem with life outside earth.
trekgeek1
5 / 5 (1) Jun 13, 2010
@notquitethinking

You show your ignorance brilliantly in that comment. Atheists don't believe in a god. Done, that's it, end of game. Anything else after that is the belief of an individual. An Atheist may believe in life outside of earth or they may not. It all depends on their scientific opinions on whether conditions necessary for life are present elsewhere in the universe. Even if that first part wasn't nonsense, what connection would making things up as you go have with life outside of earth? Your last line was intended only as an insult you unctuous, sniveling, christian. See, not very civil, is it?
freethinking
1 / 5 (4) Jun 13, 2010
trekgeek1, your hate of Christians is worse than SH or even PE. My comment was to the point that nothing in the bible rules out that life can exist outside the earth. My slam was to the ignorant people who say the bible proves life cant exist outside the earth and to athiests who says Christians will have a melt down if life is found outside the earth.
trekgeek1
5 / 5 (1) Jun 13, 2010
Worse than SH or PE? Sir, you flatter me. I merely aspire to become greater. My hateful comment was intended to illustrate how an insult does not add to the argument. I realize your slam was much more subtle, but I needed to be more obvious so that my point would be seen.
simonl
1 / 5 (2) Jun 14, 2010
Could all of you please stay on topic and take this crap elsewhere? Sick and tired of yet another discussion degenerating into this.
tj10
1 / 5 (4) Jun 14, 2010
I'm surprised Physorg.com had the courage to publish such ridiculous speculation on a science site. There is no evidence whatsoever for his ideas. Science is about observations and there is nothing about a planet that has a surface that varies in temperatures from 1649°C(hot lava lakes and -130°F,(frozen sulfur dioxide snowfields) Oh yea, then there is the little problem of Jupiter's surface being bathed in Jupiter’s deadly radiation. But hey, who am I, a non-scientist, to tell a SCIENTIST that he is wrong? I should just bow at his feet, accept his ideas as gospel truth, and petition my congressman to fund a multi-trillion dollar trip to IO with my tax money to look for life. After all, MAYBE there was liquid water there in the past. This type of hype goes to show just how desperate evolutionists are to find that elusive life in outer space. As long as they can keep coming up with new possible frontiers for life, their theory remains afloat although their faith must be weakening
tj10
1 / 5 (4) Jun 14, 2010
I'm surprised Phys org had the courage to publish such ridiculous speculation. That is not science! There's no evidence whatsoever for his ideas. There is nothing about a planet that has a surface that varies in temperatures from 1649°C(hot lava lakes and -130°F.(frozen sulfur dioxide snowfields) Oh yea, then there is the little problem of Jupiter's surface being bathed in Jupiter’s deadly radiation. But hey, who am I, a non-scientist, to tell a SCIENTIST that he is wrong? I should just bow at his feet, accept his ideas as gospel truth, and petition my congressman to fund a multi-trillion dollar trip to IO with my tax money to look for life. After all, MAYBE there was liquid water there in the past. This type of hype goes to show just how desperate evolutionists are to find that elusive life in outer space. As long as they can keep coming up with new possible frontiers for life, their theory remains afloat although their faith has to be weakening.
tj10
1 / 5 (4) Jun 14, 2010
I'm surprised Phys org had the courage to publish such ridiculous speculation. That’s not science! There is no evidence whatsoever for his ideas. There is nothing about a planet that has a surface varying in temperature from 1649°C(hot lava lakes) to -130°F.(frozen sulfur dioxide snowfields). Oh yea, then there is the little problem of Jupiter's surface being bathed in Jupiter’s deadly radiation. But hey, who am I, a non-scientist, to tell a SCIENTIST that he is wrong? I should just bow at his feet, accept his ideas as gospel truth, and petition my congressman to fund a multi-trillion dollar trip to IO with my tax money to look for life. After all, MAYBE there was liquid water there in the past. This type of hype goes to show just how desperate evolutionists are to find that elusive life in outer space. As long as they can keep coming up with new possible frontiers for life, their theory remains afloat, and more importantly, they get paid. I would think though that their faith
freethinking
1 / 5 (3) Jun 14, 2010
tj10,

I'm all for space exploration and I don't think this has anything to do about evolution.

Arguing the point that it is a waste of money MIGHT be a good point, as there might not be life, though I disagree.