Ancient Mars Was Wet and Wild

By John Wenz | May 19, 2016 12:05 pm
An artist's rendering of what a wet, ancient Mars might look like. (Credit: Wikimedia Commons)

An artist’s rendering of what a wet, ancient Mars might look like. (Credit: Wikimedia Commons)

Not only was Mars once a wet planet. New evidence, published today in Nature’s Scientific Reports, paints a picture of violent tsunamis as well.

Tsunamis on Earth are often caused by earthquakes on the ocean floor or similar events. To an extent, that’s also what happened on Mars during both its violent events. But the initial culprits in this case were giant meteorites smacking the planet. The first meteorite, which delivered a head-on blow to Mars about 3.4 billion years ago, created a 30 km (18.6 mi) impact scar while catapulting waves hundreds of meters high across vast distances.

Drawing a Line

The proof — according to lead author Alexis Rodriguez , a senior scientist at the Planetary Science Institute — is in a series of strange water erosion lines. They don’t quite look like a shoreline — and indeed, these same lines were used to initially cast doubt on the theories of northern hemisphere oceans. But seen in a different light, they’re where a giant wave smashed into terrestrial portions, dragging away a backwash of rocks, boulders, and other geologic features.


A map demonstrating the effects two meteorites had on the surface of Mars, with the scars of ancient tsunamis seen today on the surface. (Credit: Alexis Rodriguez / PSI)

“As the wave moves up, it loses energy, then gravity pulls it back into the ocean,” Rodriguez says.

The second event is the really weird one. It happened between 3 and 15 million years after the first. In the interim, Mars became a much colder place. There was still an ocean, but portions of it were frozen over, with “glacier lakes” within the ice at some points. The ocean was likely very, very briny, from evaporation leaving salts behind.

“It was a time of change,” Rodriguez says. “The planet became much colder after the first tsunami.”

The second meteorite crashed in, about the same size as the first. It smacked into the ocean, pushing frozen, brackish water out in tsunami-like waves. But where the first wave was able to create a sort of “backwash,” the second one seems to have frozen in place. Indeed, the waves of that event lurk just below the surface of Mars today.

“As the wave propagates, it spreads out and becomes thinner, and that would accelerate the freezing process,” Rodriguez says.

Here on Earth

It’s not an unprecedented occurrence. Rodriguez points me to a much more recent event that shows what he’s talking about. A video from 2013 captures when seismic activity triggered a tsunami-like flow of ice and frigid water across the wilds of Canada.

“That’s a proof of concept, that these flows happen on Earth,” he says.

The Mars data, taken from various orbiters including the Mars Global Surveyor and ESA’s Mars Express, paint a view of a world in upheaval. There’s solid evidence for these two tsunami events, but that doesn’t preclude more events yet to be discovered. Indeed, Rodriguez says they might have happened every few million years.

“The discovery of martian mega-tsunami deposits removes much of the controversy, which for decades surrounded the early Mars ocean hypothesis,” Rodriguez says.

This article originally appeared on

CATEGORIZED UNDER: Space & Physics, top posts
  • vadakkus

    The fourth planet form the star had once a civilization of sentient beings with very high levels of technological advancement, their origin being another star system in the Universe, migrants from tyrannical oppressors. Their primary source of energy was burning of hydrocarbon-based fuels out of resources that were found in plenty on and under the surface of the planet. Over the centuries, they however burned them way too much that it lead to cataclysmic climate change that led to earthquakes and tsunamis so severe that took off a layer off the crust of Mars, killing all vegetation and leaving it a barren desert hellhole.

    As energy was virtually free, they grew lazy, decadent and corrupt, but some of them used that energy and their time to develop high levels of technological advancement including means for interstellar travel. Their nearest also had life, filled with vegetation and huge murderous lizards. They seeded that planet with lifeforms of their kind engineered to one day turn into intelligent, prominent lifeforms capable of technological development. They even bombarded the planet with an asteroid to wipe out the lizards who would prevent their kind from evolving. When it became clear to them that their planet was doomed, they left the place in their spaceship to their original star system that had by then developed into a trans-dimensional paradise.

    The lifeforms they had seeded in the nearby planet, in some kind of trans-interstellar-civilizational hangover are now burning hydrocarbon-based fuels changing their planets climate. They however, are extremely backward both technologically and and when their planet perishes, they will die out with it. However, the beings they created are watching, and they have decided on a plan….

    • Lyle Hardin

      Nice short SciFi story. Are you published?

      • vadakkus

        Not yet :)

    • GravityTicker

      Very nice indeed, congratulations. That “they have decided on a plan….” got me wanting to know the rest… Oh, by the way, Elon Musk tweet got me here. (Sorry for my rusty English)

      • vadakkus

        Working on it :) Yeah Elon Musk is a hero.

        • watcherofolde

          he wets the bed

    • John C

      Sounds like Scientology Level XII

      • vadakkus

        To be honest, all I know about Scientology is that it has got something to do with Tom Cruise.

        • cv

          Yes, I also know Tom Cruise. He’s one of us.

    • tigertoo

      Great Imagination!! Well done.

      • Janice1425

        what Walter answered I am amazed that some people able to make $4137 in 4 weeks on the internet . blog link CLCK.RU/9vGvY


    • John Glasco

      Just before they left, they used the energy and time they had left to remove all traces of their vastly superior technology and even their mundane technology from the surface of the planet. They also inexplicably sifted through every minute particle of their soil to remove all traces of the once teeming lifeforms.

      • cv

        We used nanobots, John Glasco.

  • dmac

    And they call me crazy .. our DNA is found in all life with a internal skeleton ..

    • OWilson

      They called Einstein crazy, they called Dale crazy!

      • Caffeination / Joseph Dunphy

        And they called the guy who thinks he’s Napoleon crazy! My G-d, it’s a conspiracy! :)

  • John C

    Small asteroids repeatedly smashing into microbe rich cold briny oceans on a planet with less gravity than Earth. Seems like the perfect way to seed your neighboring planet.

  • Mike Richardson

    Though large impacts are generally not a good thing for complex life forms, the asteroid bombardment of wet Mars could have produced additional habitats for primitive life, as well as delivering additional chemical ingredients to potentially serve as catalysts for the emergence of life. Formerly water-filled craters and basins filled by the tsunami overflow might be good places to focus a search for microbial fossils, or possibly even live subsurface microbes, during future missions to Mars.

  • donfitness

    Too bad there was nothing there to witness it.


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