Scientists confirm that parts of earliest genetic material may have come from the starsJune 16, 2008Scientists have confirmed for the first time that an important component of early genetic material which has been found in meteorite fragments is extraterrestrial in origin, in a paper published on June 15, 2008 Scientists have confirmed for the first time that an important component of early genetic material which has been found in meteorite fragments is extraterrestrial in origin, in a paper published on 15 June 2008. The finding suggests that parts of the raw materials to make the first molecules of DNA and RNA may have come from the stars.
The scientists, from Europe and the USA, say that their research, published in the journal Earth and Planetary Science Letters, provides evidence that life's raw materials came from sources beyond the Earth. The materials they have found include the molecules uracil and xanthine, which are precursors to the molecules that make up DNA and RNA, and are known as nucleobases. The team discovered the molecules in rock fragments of the Murchison meteorite, which crashed in Australia in 1969. They tested the meteorite material to determine whether the molecules came from the solar system or were a result of contamination when the meteorite landed on Earth. The analysis shows that the nucleobases contain a heavy form of carbon which could only have been formed in space. Materials formed on Earth consist of a lighter variety of carbon. Lead author Dr Zita Martins, of the Department of Earth Science and Engineering at Imperial College London, says that the research may provide another piece of evidence explaining the evolution of early life. She says: "We believe early life may have adopted nucleobases from meteoritic fragments for use in genetic coding which enabled them to pass on their successful features to subsequent generations." Between 3.8 to 4.5 billion years ago large numbers of rocks similar to the Murchison meteorite rained down on Earth at the time when primitive life was forming. The heavy bombardment would have dropped large amounts of meteorite material to the surface on planets like Earth and Mars. Co-author Professor Mark Sephton, also of Imperial's Department of Earth Science and Engineering, believes this research is an important step in understanding how early life might have evolved. He added: "Because meteorites represent left over materials from the formation of the solar system, the key components for life -- including nucleobases -- could be widespread in the cosmos. As more and more of life's raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely." Imperial College London | |||||||||||||||||||||
|
Related Meteorite News Articles Cosmic connections: Imperial scientist locates the origin of cosmic dust The research, published in the journal Geology, shows that some of the cosmic dust falling to Earth comes from an ancient asteroid belt between Jupiter and Mars. This research improves our knowledge of the solar system, and could provide a new and inexpensive method for understanding space. Bringing Martian samples to Earth -- preparations outlined in journal Astrobiology A critical component of NASA's Mars exploration program involves bringing planetary samples back to Earth for in-depth analysis, plans for which are detailed in the latest issue of Astrobiology, a peer-reviewed journal published by Mary Ann Liebert, Inc. The report is available free online at www.liebertpub.com/ast Tunguska catastrophe: Evidence of acid rain supports meteorite theory The Tunguska event is regarded as one of the biggest natural disasters of modern times. On 30 June 1908 one or more explosions took place in the area close to the Tunguska River north of Lake Baikal. The explosion(s) flattened around 80 million trees over an area of more than 2000 square kilometres. Discovery of the source of the most common meteorites When observing with the GEMINI telescopes, two astronomers from Brazil and the United States discovered for the first time asteroids that are similar to "ordinary chondrites", the most common meteorites found on Earth. Until now, astronomers have failed to identify their asteroidal sources because of the various geologic processes that occur after the meteorites are ejected from their asteroidal parent body. Laser fluorescence could find life on Mars A team of scientists from the United States and the United Kingdom has developed a technique using ultraviolet light to identify organic matter in soils that they say could be used to document the existence of life on Mars. FSU geochemist challenges key theory regarding Earth's formation Working with colleagues from NASA, a Florida State University researcher has published a paper that calls into question three decades of conventional wisdom regarding some of the physical processes that helped shape the Earth as we know it today. Geologists Discover New Way of Estimating Size and Frequency of Meteorite Impacts Scientists have developed a new way of determining the size and frequency of meteorites that have collided with Earth. Meteorites delivered the 'seeds' of Earth's left-hand life Flash back three or four billion years - Earth is a hot, dry and lifeless place. All is still. Without warning, a meteor slams into the desert plains at over ten thousand miles per hour. With it, this violent collision may have planted the chemical seeds of life on Earth. UMd-led team finds ancient asteroids formed at solar system's start Using visible and infrared data collected from telescopes on Hawaii's Mauna Kea, a team of scientists, led by the University of Maryland's Jessica Sunshine, have identified three asteroids that appear to be among our Solar System's oldest objects. Meteorites a rich source for primordial soup The organic soup that spawned life on Earth may have gotten generous helpings from outer space, according to a new study. Scientists at the Carnegie Institution have discovered concentrations of amino acids in two meteorites that are more than ten times higher than levels previously measured in other similar meteorites. More Meteorite News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||