Earth life 'may have come from Mars'

 
Gale crater, Mars Life would face challenges on Mars today, but billions of years ago conditions might have been better

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Life may have started on Mars before arriving on Earth, a major scientific conference has heard.

New research supports an idea that the Red Planet was a better place to kick-start biology billions of years ago than the early Earth was.

The evidence is based on how the first molecules necessary for life were assembled.

Start Quote

The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock”

End Quote Prof Steven Benner Westheimer Institute for Science and Technology

Details of the theory were outlined by Prof Steven Benner at the Goldschmidt Meeting in Florence, Italy.

Scientists have long wondered how atoms first came together to make up the three crucial molecular components of living organisms: RNA, DNA and proteins.

The molecules that combined to form genetic material are far more complex than the primordial "pre-biotic" soup of organic (carbon-based) chemicals thought to have existed on the Earth more than three billion years ago, and RNA (ribonucleic acid) is thought to have been the first of them to appear.

Simply adding energy such as heat or light to the more basic organic molecules in the "soup" does not generate RNA. Instead, it generates tar.

RNA needs to be coaxed into shape by "templating" atoms at the crystalline surfaces of minerals.

The minerals most effective at templating RNA would have dissolved in the oceans of the early Earth, but would have been more abundant on Mars, according to Prof Benner.

Red or dead

This could suggest that life started on the Red Planet before being transported to Earth on meteorites, argues Prof Benner, of the Westheimer Institute of Science and Technology in Gainesville, US.

Why is Mars so lifeless?

Mars taken by Mars Global Surveyor
  • No magnetic shield: Mars' magnetic field disappeared four billion years ago, allowing the solar wind to strip away the planet's atmosphere
  • The missing atmosphere: Mars has just 1% of Earth's atmospheric pressure, so heat from the Sun escapes into space, making the planet very cold
  • Too cold for liquid water: Mars sits outside the so-called Goldilocks Zone where the temperature is 'just right' for water to remain liquid - vital for life as we know it

The idea that life originated on Mars and was then transported to our planet has been mooted before. But Prof Benner's ideas add another twist to the theory of a Martian origin for the terrestrial biosphere.

Here in Florence, Prof Benner presented results that suggest minerals containing the elements boron and molybdenum are key in assembling atoms into life-forming molecules.

The researcher points out that boron minerals help carbohydrate rings to form from pre-biotic chemicals, and then molybdenum takes that intermediate molecule and rearranges it to form ribose, and hence RNA.

This raises problems for how life began on Earth, since the early Earth is thought to have been unsuitable for the formation of the necessary boron and molybdenum minerals.

It is thought that the boron minerals needed to form RNA from pre-biotic soups were not available on early Earth in sufficient quantity, and the molybdenum minerals were not available in the correct chemical form.

Shergottite meteorite from Mars Meteorites from Mars have been arriving on Earth throughout our planet's history

Prof Benner explained: "It’s only when molybdenum becomes highly oxidised that it is able to influence how early life formed.

"This form of molybdenum couldn’t have been available on Earth at the time life first began, because three billion years ago, the surface of the Earth had very little oxygen, but Mars did.

"It’s yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite, rather than starting on this planet."

Early Mars is also thought to have had a drier environment, and this is also crucial to its favourable location for life's origins.

"What’s quite clear is that boron, as an element, is quite scarce in Earth’s crust," Prof Benner told BBC News, “but Mars has been drier than Earth and more oxidising, so if Earth is not suitable for the chemistry, Mars might be.

"The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock," he commented.

"It’s lucky that we ended up here, nevertheless - as certainly Earth has been the better of the two planets for sustaining life. If our hypothetical Martian ancestors had remained on Mars, there may not have been a story to tell."

 

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  • rate this
    +1

    Comment number 180.

    I wonder if this was the result of the massive asteroid impacts that wiped out Mars's atmosphere. I'm not familiar with the timeline, but it would make sense that material taken from Mars on top of the remainder asteroid after impact could be sent to earth.

  • rate this
    -7

    Comment number 179.

    165. paulmerhaba
    JUST NOW
    We patiently await the scientific community to prove that 1+1=2.
    I mean it was something made up by some geezers a long time ago, wasn't it?

    There is a mathematical proof showing that 2+2=5

  • rate this
    -4

    Comment number 178.

    I wrote a theory on this 16 years ago, and people used to tell me, "Don't tell anyone else about that, they will laugh at your head". I continued to talk about it, and we have a website with my theory on it.

    Mars today is what Earth will look in a couple of thousand years, and we will move to another planet not far from Earth. This planet is yet to be discovered.

  • rate this
    +7

    Comment number 177.

    162. Luther_Wesley-Baxter

    #133
    Nothing is impossible for God, so no weight, however heavy, would be impossible for God to lift. God speaks and it is done.

    Hilarious.

  • rate this
    0

    Comment number 176.

    I did read one theory that life came to this planet as the result of another species ejecting all their waste into space millions of years ago.

    We're already dumping some junk in orbit, so the cycle is set to repeat itself.

  • rate this
    +3

    Comment number 175.

    Oh shutup DemoDave no-one knows where their taxes go because funnily enough we don't exactly recieve a reciept every month detailing it. Most of these studies are privately funded or are put on by universities for trainee researchers so they can get a handling of the procedure.
    But hey don't let me spoil your Daily Mail-esque rant about what your taxes go to.

  • rate this
    +4

    Comment number 174.

    Additionally, this entire solar system is 2nd hand!

    We're part of the second set of planets that have been in this vicinity, formed, lived & died in a stellar death... so life may have originated in the previous solar system that was here & been re-seeded from there.

    The Oort Cloud may contain life from the previous system... explaining why life got started on Earth so fast after cooling.

  • rate this
    +5

    Comment number 173.

    All these comments about GOD creating everything. As if such a being could possibly exist had not early man found it necessary to invent it. And hundreds of generations later, some of his descendants still swallow the mantra - amazing

  • rate this
    +6

    Comment number 172.

    David Bowie will be pleased , he's been asking if there's life on Mars since 1971

  • rate this
    -3

    Comment number 171.

    I'm in the middle here... we're still unable to get the next days weather correct but scientists can say we may have come from Mars? Not sure why religion and god always seems to be mentioned at the thought of life creation... i think we've all heard of evolution just probably not from Mars

  • rate this
    +5

    Comment number 170.

    DaveB @147, could your mighty creator not have stared with a big bang, then life on mars, transfered it to earth and evolved it to us via the apes? or is he/she/it too rubbish for such a convoluted creation? There is no god. wake up.

  • rate this
    0

    Comment number 169.

    Did someone watch Mission To Mars and then write this? :-)

  • rate this
    +10

    Comment number 168.

    82. Global Yawning

    We were all from Africa yesterday. At least religions stick to their stories
    ----
    You're hit the nail squarely on the head there - "Story".

  • rate this
    -9

    Comment number 167.

    My belief,,, there is a greater power than mankind,, all this money spent on all this research would be better spent on cancer research.

  • rate this
    +7

    Comment number 166.

    @ So science as telling us we're all aliens now. And atheist in here have the gall to mock religion!!

    We were all from Africa yesterday. At least religions stick to their stories
    ------------------------------------------------------------------------------------------------------

    This is because monotheistic religions seem to have a lot of difficulty in admitting when they're wrong....

  • rate this
    -4

    Comment number 165.

    We patiently await the scientific community to prove that 1+1=2.
    I mean it was something made up by some geezers a long time ago, wasn't it?

  • rate this
    +4

    Comment number 164.

    And crawling on the planets face, some insects, called the human race, lot in time, and, lost in space.... and meaning.

  • rate this
    +2

    Comment number 163.

    Wasn't this being bandied about years ago as an explanation for life on earth?

    Also, there should be a story on how if we are all God's children, what makes Jesus so special? Would love to see the HYS on that one :)

  • rate this
    -97

    Comment number 162.

    #133
    Nothing is impossible for God, so no weight, however heavy, would be impossible for God to lift. God speaks and it is done.

  • rate this
    +4

    Comment number 161.

    @121.Luther_Wesley-Baxter

    Except that we found eggs that date from way way way before the first chicken. Egg came first. Actually a really easy question to answer once you have the knowledge of evolution.

 

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