Ancient Mars bombardment likely enhanced life-supporting habitat

CU study: Ancient Mars bombardment likely enhanced life-supporting habitat
Ancient impacts on Mars likely enhanced climate conditions for life. Credit: NASA

The bombardment of Mars some 4 billion years ago by comets and asteroids as large as West Virginia likely enhanced climate conditions enough to make the planet more conducive to life, at least for a time, says a new University of Colorado Boulder study.

CU-Boulder Professor Stephen Mojzsis said if early Mars was as barren and cold as it is today, massive asteroid and comet impacts would have produced enough heat to melt subsurface ice. The impacts would have produced regional hydrothermal systems on Mars similar to those in Yellowstone National Park, which today harbor chemically powered microbes, some of which can survive boiling in hot springs or inhabiting water acidic enough to dissolve nails.

Scientists have long known there was once running water on Mars, as evidenced by ancient river valleys, deltas and parts of lake beds, said Mojzsis. In addition to producing hydrothermal regions in portions of Mars' fractured and melted crust, a massive impact could have temporarily increased the planet's atmospheric pressure, periodically heating Mars up enough to "re-start" a dormant water cycle.

"This study shows the ancient bombardment of Mars by comets and asteroids would have been greatly beneficial to life there, if life was present," said Mojzsis, a professor in the geological sciences department. "But up to now we have no convincing evidence life ever existed there, so we don't know if early Mars was a crucible of life or a haven for life."

Published in Earth and Planetary Science Letters, the study was conducted by Mojzsis and Oleg Abramov, a researcher at the U.S. Geological Survey in Flagstaff, Arizona and a former CU-Boulder research scientist under Mojzsis.

Much of the action on Mars occurred during a period known as the Late Heavy Bombardment about 3.9 billion years ago when the developing solar system was a shooting gallery of comets, asteroids, moons and planets. Unlike Earth, which has been "resurfaced" time and again by erosion and plate tectonics, heavy cratering is still evident on Mercury, Earth's moon and Mars, Mojzsis said.

Mojzsis and Abramov used the Janus supercomputer cluster at the University of Colorado Computing facility for some of the 3-D modeling used in the study. They looked at temperatures beneath millions of individual craters in their computer simulations to assess heating and cooling, as well as the effects of impacts on Mars from different angles and velocities. A single model comprising the whole surface of Mars took up to two weeks to run on the supercomputer cluster, said Mojzsis.

The study showed the heating of ancient Mars caused by individual asteroid collisions would likely have lasted only a few million years before the Red Planet - about one and one-half times the distance to the sun than Earth - defaulted to today's cold and inhospitable conditions.

"None of the models we ran could keep Mars consistently warm over long periods," said Mojzsis.

While Mars is believed to have spent most of its history in a cold state, Earth was likely habitable over almost its entire existence. A 2009 study by Mojzsis and Abramov showed that the Late Heavy Bombardment period in the inner solar system nearly 4 billion years ago did not have the firepower to extinguish potential early life on Earth and may have even given it a boost if it was present.

"What really saved the day for Earth was its oceans," Mojzsis said. "In order to wipe out life here, the oceans would have had to have been boiled away. Those extreme conditions in that time period are beyond the realm of scientific possibility."

The new Mars study was funded by NASA and the John Templeton Foundation. Mojzsis recently received an $800,000 grant from the Foundation for Applied Molecular Evolution in Alachua, Florida made possible by the Templeton Foundation to better understand early Earth and the beginning of life before about 4 billion years ago.

"Studies of Mars provide us with valuable information about our own place in the solar system," he said. "Our next steps are to model similar bombardment on Mercury and Venus to better understand the evolution of the inner and apply that knowledge to studies of planets around other stars."

Mojzsis will meet with scientists from the California Institute of Technology and NASA's Jet Propulsion Laboratory in Pasadena next month to discuss possible landing sites and research targets for the upcoming Mars 2020 rover mission. Mars 2020 will carry instruments to seek out past life or present , hunt for habitable areas and demonstrate technologies for use on future robotic and human missions to Mars.


Explore further

Asteroid Attack 4 Billion Years Ago May Have Accelerated Life on Earth

More information: Thermal Effects of Impact Bombardments on Noachian Mars, Oleg Abramov & Stephen J. Mojzsis, 2016 May 15, Earth and Planetary Science Letters, www.sciencedirect.com/science/ … ii/S0012821X16300528
Citation: Ancient Mars bombardment likely enhanced life-supporting habitat (2016, April 5) retrieved 25 June 2019 from https://phys.org/news/2016-04-ancient-mars-bombardment-life-supporting-habitat.html
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Apr 05, 2016
"Mars bombardment likely enhanced life-supporting habitat"

Causing a well-designed bombardment of Mars to enhance life-supporting habitat would be our version of what nature did with Mars the first time around. We would be wise to learn as much as we can about this and use it to accelerate terraforming on Mars.

Apr 05, 2016
Science has shown that
@barf
no, it hasn't
just because we haven't gotten the answer yet doesn't mean we will not ever get the answer... case in point: Newtonian physics and GR/SR
Nowhere have we ever observed evolution
you mean besides everywhere? or Lenski?
(and I mean the real macroevolution)
you mean like the dozens of transitional fossils between Lucy and modern homo sapiens sapiens?
yeah... keep on dreaming, religious girlie

what is even more confusing is: why would you care about science and reality when you're obviously training yourself and your offspring to ignore reality for the sake of a delusion?

if ti aint real, why can you live more than twice as long as you could just a few hundred years ago when religion ruled the world?

go back to your fundie site

Apr 05, 2016
Who the heck gives someone a 1 for being in favor of terraforming Mars? And why? Dumb da dumb dumb.

5 for you, @Mark.

Meanwhile, @BartV,
Life just doesn't arise spontaneously.
Why not? It's just chemicals.

Nowhere have we ever observed evolution (and I mean the real macroevolution).
See "ring species." Babble thumper fail.

And no, I didn't give you a 1; I can't because I have all the babble thumpers on ignore. I just figured I had to see who was dumb enough to give someone a 1 for being in favor of terraforming Mars.

Apr 06, 2016
I doubt 1.5million years would be sufficient to spark life into action. The chemical cooking process alone takes longer than that. That said, its like a spark, had some life emerged the terraforming process would have begun. Sadly, close but no cigar.
I am all for terraforming mars. I think we should quit with this sterile lander bullshit and just let our microbes go and try make the best of it. I also like the idea of nuking the poles to generate heat, think its a viable means of getting rid of nuclear stockpiles and potentially setting up planet 2. Think about the television we could watch while nuke after nuke slammed into the martian poles:)

Apr 06, 2016
I think we should quit with this sterile lander bullshit and just let our microbes go and try make the best of it
@jayded
i'm not sure this is a good idea
this is offered all IMHO

if we run into alien life, it will likely not be compatible with us because our life emerged and is adjusted specifically to existence on our rock... our microbes and life may well be deadly or completely benign to any alien life and vice versa. it's a crap shoot and anyone's guess because we just don't have examples of life outside of earth

however, if we expose our life to other worlds and it mutates beyond what it is now, it has a far, far greater potential to bite us on the buttocks later on because it's foundation is also the same as ours

Apr 06, 2016
+Jayded Nice idea, but I think that the risks of transporting our nuclear stockpiles into space are enormous, you wouldn't want that rocket exploding on launch now would you?

Apr 06, 2016
Da Schneib, why are people calling other people dumb for not supporting an impossible plan?

Unless we can start or re-start a geodynamo in the core of the planet, nuking or diverting asteroids to strike the poles in a bid to increase atmospheric pressure and release water isn't going to help much.

The atmosphere will still be stripped away by the solar wind without a protective magnetosphere, and the radiation environment on the planets surface will remain very inhospitable.

We would also have to deal with Phobos' predicted break-up and the resulting pummeling of the planet after all our hard work in about 10+ million years.

It's an awesome science-fiction idea, but entirely unrealistic.

Apr 09, 2016
Doesn't make any difference if you think Mars has a "life-supporting" environment. Life just doesn't arise spontaneously. And Evolution just doesn't happen. Science has shown that. Nowhere have we ever observed evolution (and I mean the real macroevolution). Why are we wasting our time on such nonsense?



All the facts suggest you are in error.

Macro-evolution? Camels can have viable offspring with Llamas. Like horses, camels evolved in North America and migrated to Asia, Africa and South America.

Apr 09, 2016
Sigh. I like Mojzsis work, but he is now another JT sell out.

@Jayded: "I doubt 1.5million years would be sufficient to spark life into action. The chemical cooking process alone takes longer than that."

Estimates narrow it down to 10 - 100 kyrs upper limit in soup (10 kyrs) and vent (100 kyrs) theories. Both estimates are feasible vs how much 'cooking' has to happen and the reaction rates involved.

@Azrael: "The atmosphere will still be stripped away".

Which will take ~ 1 billion years if the atmosphere is supplied to ~ 1 Earth atmosphere at the outset. (Admittedly, it won't be breathable at the end.)

There is no known show stopper for terraforming Mars. (Nitrogen is scarce, so you have to use closed habitats for growing plants.)


Apr 09, 2016
Da Schneib, why are people calling other people dumb for not supporting an impossible plan?

1. It's not impossible. It's very possible given foreseeable technology based on things we already know how to do.
2. Given that, it's dumb to downrate someone for talking about it, and even dumber to do so without replying *on subject* to someone talking about it, and the only replies at the time were babble thumpers who didn't read enough to figure out we're not talking about the origin of life but about terraforming.

Unless we can start or re-start a geodynamo in the core of the planet, nuking or diverting asteroids to strike the poles in a bid to increase atmospheric pressure and release water isn't going to help much.
It will help a lot. Granted, without a geodynamo the atmosphere won't last forever, but it will last many orders of magnitude longer than any human society has ever lasted so far. Sounds like a good investment to me.

[contd]

Apr 09, 2016
[contd]
We would also have to deal with Phobos' predicted break-up and the resulting pummeling of the planet after all our hard work in about 10+ million years.
Ten million years is a really, really long time to amortize your investment. Still sounds good to me. And if we can move asteroids to bring the water and all that, Phobos looks like it won't be much of a problem to move out so it doesn't break up.

Overall I think it's something we can and will do, though probably not for hundreds of years.

Apr 11, 2016
Phobos could be used for construction material and reaction mass.

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