Bacteria Survive in Cold, Dry, Mars-like Conditions By Living Off Iron

By Valerie Ross | January 4, 2012 2:09 pm

An image of the Martian surface from NASA’s Viking 2

To eke out even the barest subsistence on Mars, a living thing would have to adapt to a formidable set of environmental challenges: an arid, often extremely cold landscape with miniscule amounts of oxygen in the atmosphere and no organic matter to eat. During a recent foray into a similarly inhospitable part of our own planet, scientists have discovered several species of bacteria that hint at what life on Mars, if it exists, might look like. These microbes survive on minerals in the surrounding rocks—minerals also found in the Martian surface.

The bacteria were living beneath a thin layer of ice coating a lava tube, a subterranean tunnel lava once flowed through, high in the Cascade Mountains. These frigid, dry conditions—an environment similar to Mars, albeit less extreme—are devoid of typical food sources, and the layer of ice blocks out much of the oxygen from the atmosphere. Rather than breaking down sugars and other nutrients, the bacteria have evolved to get by on what’s available: lots and lots of rock. They glean energy from a simple chemical reaction with the iron in olivine, a mineral abundant in the basalt rock of the lava tube and present in rocks on Mars as well. If olivine can sustain life in a milder proxy of the Martian environment, that gives researchers something to look for when searching for life on the red planet.

Scientists frequently look to the extremophile microbes living in Earth’s coldest, hottest, driest, most acidic, or least aerobic environments when exploring the possibility of extraterrestrial life. In 2009, another research team found a hundred bacterial species living miles deep in the dry, low-oxygen vents of an Andean volcano—another environment to analogous to Mars, and more possible blueprints on which to base the search for Martian life.

Image courtesy of NASA

CATEGORIZED UNDER: Living World, Space
  • Bobby LaVesh

    The next study should be to see how cold an environment we can get those bacteria to live in.

    See if we can “speed up” evolution in the lab to produce a variant of the bacteria that COULD live on mars.

    The only problem with Olivine as a food source- with no predator or means of removing the bacteria- if a theoretical living martian bacteria “ate” olivine- how would we explain olivine on mars?

    Something would have to produce more Olivine to fuel the bacteria.

  • Doron

    True in principle, but we could imagine harsh, extreme conditions limiting absolute volume of bacteria population or slowing speed of reproduction and metabolism

  • Checkmate1

    Well, one cannot assume zero predation, but are there ongoing processes on Mars which continue to produce iron rich deposits? Maybe not Olivine, but something analogous and usable as a metabolic fuel?

  • Ron Bennett

    This site sounds very close to the Phoenix Landers site on Mars where there were some questionable findings that suggested that large micro-organisms were moving around in the soil. At the Phoenix Lander site, the NASA science team claimed “there are all the necessary ingredients to sustain life as we know it here on earth.” Remember this is also where they conclusively determined that mars had water ice.

    Water can easily form directly under top layer of soil or an ice sheet all you need is a heat source, in this case solar radiation in the summer time is the heat source. That should be a no brainer but after repeating myself for over 12 years now no one at NASA seem to think this is true. I easily proved it in a lab with an outdated vacuum chamber, any 8th grader can do this in a lab…

    Anything that can contain gas or water vapor in an enclosed area will build up pressure, increase of pressure and heat allows water ice to sublimate into a liquid instead of a vapor like what will happen below the surface of the Mars Phoenix Lander.

    See here for youtube video of time lapse images taken from the Phoenix Landers Microscopic Imager of what appears to be rod shaped and scorpion shaped micro-organism moving around gasping for life, like fish out of water, after dug up and exposed to the much harsher extremes of the Martian atmosphere.

  • Geack

    @1. Why would we assume there’s a limited supply of olivine or some iron-rich equivalent? There’s a vast amount of iron in the earth’s crust, likely in Mars’ as well. Bacteria don’t eat much, especially in extreme conditions.

    @4. Are you seriously suggesting that people who spend their professional lives in a search for even the hint of a possibility of a tiny amount of life on Mars are for some reason ignoring plain video evidence of bugs crawling around? I’m not sure what you think you see in that video, but your whole idea makes no sense.

  • Eli

    Why could we not send a large load of this bacteria to Mars, include so of the ingredients needed for it to survive and adapt and then let it begin to spread across the planet? The oxygen that it would produce would begin to change the entire environment of Mars over time. I believe that tera-forming Mars will be critical to the expansion and survival of the Human Race in the future.

    I would be more than happy to see some of my tax dollars used to try something like this…..


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