Where do we come from? How did life come to Earth? The more common view is that in the warm oceans of the early Earth, matter gradually accumulated to form complex mixtures, followed by the emergence of RNA and DNA, which eventually formed cells and evolved complex life.
However, a new study has detected two finer structures that build DNA from 3 meteorites that fell to the earth, which makes the origin of life on Earth more confusing.
The three meteorites fell in Murray, Kentucky, in 1950, in Murchison, Victoria, Australia, in 1969, and near Lake Tagish in British Columbia, Canada in 2000.
DNA is the molecule that carries the genetic instructions in the organism, and RNA is the key molecule that controls the activity of genes, and life relies on them to replicate, pass it on from generation to generation, and it has formed a complex and diverse life system on the earth for hundreds of millions of years.
How life originates depends on where the material that makes up DNA comes from, and most scientists believe that life may be native to Earth, and that the matter on Earth has gradually formed DNA that can be copied in a long period of chemical action, eventually leading to the birth of the first life.
Five chemical components are needed to build DNA, and scientists have previously detected three of these three meteorites, and there are two more to prove that life on Earth comes from outer space. This time, a team of scientists from Hokkaido University's Cryogenic Science Institute and nasa and other scientific institutions, using more sensitive operations to fine-tune the way meteorites are analyzed, found two other nuclear bases needed to form DNA in these three meteorites- cytosine and thymine, thus proving that meteorites from outer space may have brought the main compounds needed to build DNA.
So does this mean that life comes from outer space, and we are all descendants of alien visitors? The answer is that it can't yet, and this discovery doesn't directly shed light on how life originated on Earth, because other compounds are needed to make up life, including amino acids, sugars, and fatty acids, which are proteins and enzymes, dna and RNA backbones, and cell membranes, all of which are necessary for life.
This means that there is further evidence for the conjecture that life may have come from outer space than most people have understood before, and whether there will be other life in the universe is more reason for us to be full of reverie.
The study was published in the journal Nature Communications.
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