Image caption Life would face challenges on Mars today, but billions of years ago conditions might have been better 
 
 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. 
 
 The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock 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? No magnetic shield: Mars' magnetic field disappeared four billion years ago, allowing the solar wind to strip away the planet's atmosphere 
 
 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 
 
 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 BBC Science: What makes Mars so hostile to life? 
 
 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. 
 
 Image caption 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." ||||| NASA's Hubble Space Telescope snapped this shot of Mars on Aug. 26, 2003, when the Red Planet was 34.7 million miles from Earth. The picture was taken just 11 hours before Mars made its closest approach to us in 60,000 years. 
 
 We may all be Martians. 
 
 Evidence is building that Earth life originated on Mars and was brought to this planet aboard a meteorite, said biochemist Steven Benner of The Westheimer Institute for Science and Technology in Florida. 
 
 An oxidized form of the element molybdenum, which may have been crucial to the origin of life, was likely available on the Red Planet's surface long ago, but unavailable on Earth, said Benner, who presented his findings today (Aug. 28; Aug. 29 local time) at the annual Goldschmidt geochemistry conference in Florence, Italy. [The Search for Life on Mars (Photo Timeline)] 
 
 "It’s only when molybdenum becomes highly oxidized that it is able to influence how early life formed," Benner said in a statement. "This form of molybdenum couldn’t have been available on Earth at the time life first began, because 3 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." 
 
 Organic compounds are the building blocks of life, but they need a little help to make things happen. Simply adding energy such as heat or light turns a soup of organic molecules into a tarlike substance, Benner said. 
 
 That's where oxidized molybdenum comes in. Inserting it or boron, another element, into the mix would help organics make the leap to life, Benner added. 
 
 "Analysis of a Martian meteorite recently showed that there was boron on Mars; we now believe that the oxidized form of molybdenum was there, too," he said. 
 
 Another point in Mars' favor is the likelihood that the early Earth was completely covered by water while the ancient Red Planet had substantial dry areas, Benner said. All of this liquid would have made it difficult for boron, which is currently found only in extremely dry places, to form in high enough concentrations on Earth when life was first evolving. 
 
 Further, Benner added, water is corrosive to RNA, which most researchers think was the first genetic molecule (rather than DNA, which came later). 
 
 No planet is more steeped in myth and misconception than Mars. This quiz will reveal how much you really know about some of the goofiest claims about the red planet. Start the Quiz 0 of 10 questions complete 
 
 Mars Myths & Misconceptions: Quiz No planet is more steeped in myth and misconception than Mars. This quiz will reveal how much you really know about some of the goofiest claims about the red planet. 0 of questions complete 
 
 No indigenous Red Planet organisms have ever been discovered. But it is possible that life on Mars — if it ever existed — may have made its way to Earth at some point, many scientists say. 
 
 Some microbes are incredibly hardy, after all, and may be able to survive an interplanetary journey after being blasted off their home world by an asteroid impact. And orbital dynamics show that it's much easier for rocks to travel from Mars to Earth than the other way around. 
 
 Wherever Earth life originated, Benner is glad it put down roots on our blue planet. 
 
 "It’s lucky that we ended up here nevertheless, as certainly Earth has been the better of the two planets for sustaining life," Benner said. "If our hypothetical Martian ancestors had remained on Mars, there might not have been a story to tell." 
 
 Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on SPACE.com.
– Were our earliest ancestors Martians? A new study suggests that all life on Earth may have originated on the Red Planet, the BBC reports. That's because Mars would have had plenty of the minerals that are best at forging RNA, which is one of the key components of life and is believed to have predated DNA. On Earth, those minerals would have dissolved into the ocean (water is "corrosive" to RNA, adds Space.com). But life could have formed on Mars, then headed here on meteorites, suggests US scientist Steven Benner; he's not the first to propose such a theory, the BBC notes. The investigation centers on how atoms were arranged to form RNA, DNA, and proteins. Benner says minerals containing the elements boron and an oxidized form of molybdenum were central to the process—but at the time, Earth was probably incapable of supporting enough of such minerals. He tells Space.com that analysis of a Martian meteorite revealed the presence of boron on Mars, and "we now believe that the oxidized form of molybdenum was there, too." As such, "the evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock," says Benner. "It’s lucky that we ended up here, nevertheless—as certainly Earth has been the better of the two planets for sustaining life." Click for more on how nobody really wants to head back there.