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The Dry Edge of Life: Studying “Martians” in Chile

I recently spent a week with a group of astrobiologists studying life in the Atacama Desert of northern Chile.

This is extraordinary, because the Atacama is the driest place in the world. The average annual rainfall is one millimeter, and decades can go by between rain events.

There’s not much life to study. It’s too dry for plants and animals to survive in the desert’s hyperarid core. There are no insects, no lizards, no birds, no rodents. No trees, no shrubs, no cacti. Not even lichen. Nothing but dirt, rocks and salt flats.

To a large extent, the landscape has gone unchanged for 10 to 15 million years. It looks like pictures of Mars. (Related: “Chile Desert to Prepare Robot for Life on Mars.”)

NASA scientists interested in what life may have looked like on ancient Mars therefore spent several years trying to find bacteria living in the Atacama. (Related: “Viking Mission May Have Missed Mars Life, Study Finds.”)

The salt flats turned out to be the key. They’re not exactly flat—they’re filled with bizarre, knobby rocks made of halite (table salt). The locals call these knobs flores (“flowers”), because they grow over time. Rocks like these don’t form anywhere else on Earth—nowhere else is dry enough.

In 2005, in an unnamed salt flat near the site of a former nitrate mine, Jacek Wierzchos, a researcher from Madrid, discovered a novel species of photosynthetic bacteria living inside these salt rocks.

Occasionally at night, when the relative humidity in the air increases sufficiently, the halite rocks absorb moisture from the atmosphere, and microscopic pockets of liquid brine form inside them. Because halite is translucent, it allows some sunlight to penetrate into its interior, enabling photosynthesis while screening out harmful UV radiation.

The findings from studies of these halite flowers may help guide the future search for life on Mars. Conditions similar to those in the present-day Atacama may have existed on Mars in the past.

For more information, check out my field reports on the Astrobiology Magazine website.


  1. […] (Related blog: “The Dry Edge of Life—Studying ‘Martians’ in Chile.”) […]

  2. explora
    Chile: Atacama Desert, Patagonia and Easter Island
    July 21, 2011, 11:20 am

    Hi Henry, very interesting article. We partly disagree with it. The Atacama Desert stretches for more than 1,000 km (600-miles) and it’s right a high percentage of this vast territory is to dry to have animals and plants. In spite of the geographic and climatic conditions of the desert, there are few and miraculous places all teeming with life, as are the ravines and oases which have formed around the small water courses that descend from the Andes… We invite you to to check this pictures out http://www.facebook.com/exploraexperiences Best

  3. rosanautica
    July 20, 2011, 8:40 pm

    Did you see any rocks there that seem to have moved–rocks that leave behind visible paths in the dirt? Would you know how that happens?

  4. Attia Nurani
    South Sumatra, Indonesia
    July 19, 2011, 10:21 pm

    Much think in this world we never know until we research and traveling a place like Acatama. And finnaly we get knowledge to be come use for ourself. Beautiful photo Mr.

  5. Adam Bray
    July 18, 2011, 11:11 am

    Are these never found in caves? I’ve seen nodules that look identical to these, deep in caves along the border of georgia and tennessee. What particularly strikes me is the way the nodule is attached to the substrate underneath it–the ones in the caves were attached in just such a manner.

  6. Alex Krupa
    Toronto ,Canada
    July 18, 2011, 8:38 am

    It is amazing ! Lives is everywhere !!
    Congratulation Jacek !!!!

  7. Vikas Sharma
    Chandigarh, India
    July 18, 2011, 5:27 am

    I think spiritual rain could be caused over there with the help of Kundalini. I have done more than 15 years of research on this subject and think so that can cause climate change with the help of Kundalini.

  8. Adrian Holmes
    Sydney, Australia.
    July 17, 2011, 5:24 pm

    I am trying to understand why I feel comforted by this!

  9. Angel Cantie
    United States
    July 16, 2011, 1:20 pm

    Question, how did these flowers develope and stay uniform?

    • Henry Bortman
      July 17, 2011, 9:03 am

      Angel, they are not uniform. They come in many shapes and sizes. The formation process is described in my article “Islands of Life, Part III“.

  10. Caitlin Liebmann
    Western Australia
    July 16, 2011, 8:46 am

    Why we should always keep our minds open…

  11. Lakhdar Still
    July 16, 2011, 7:55 am

    it’s fantastic places like this. But in Algiers there are better places than these, you could exploring it

    July 16, 2011, 7:27 am

    That’s nice picture

  13. yasmin
    saudi arabia
    July 16, 2011, 7:19 am

    Congratulations for Jacek and his investigations!!! to find life in these halite rocks is just incredible and fascinating, it shows that all in this universe is “alive” …….for sure! thanks for sharing this really interesting article mr. Bortman.

  14. cheyne alvis formalejo
    July 16, 2011, 6:31 am

    very interesting place indeed! nice photos too

  15. The Platzner Post
    Chicago, IL
    July 16, 2011, 4:18 am


  16. Becker, M.
    Yuma, AZ
    July 16, 2011, 3:24 am

    Truly amazing to witness endless survival-ability of life’s energies.

  17. dua khan
    July 16, 2011, 2:03 am

    nice program

  18. Darlene
    July 16, 2011, 2:02 am

    Justin do you have a facebook?

  19. Torbjörn Larsson, OM
    July 15, 2011, 11:51 pm

    Amazing. One of the driest, and I think most diurnal temperature cycling (?) places on Earth and it helps hiding out in *salt* and salty brines!?

  20. Margaret Power
    July 15, 2011, 7:09 pm

    Hey! What did you think of Chile? Did you go to Iquique? It was so neat to read your article.

  21. Yadvendra Singh
    New delhi, India
    July 15, 2011, 3:19 pm

    i like it.its nice to see the life like these places.

  22. cdalton
    Atlanta, Georgia
    July 14, 2011, 5:41 pm

    This is extremely interesting, salt flowers in a place where there is no life?

  23. Justin Morell
    July 14, 2011, 2:13 pm

    Fascinating. And beautiful photos!