B.C. meteorite suggests life on Earth came from space
The space rock first made headlines in 2000, when it streaked across the northern skies and crashed to Earth along the B.C.-Yukon border. It was back in the news in 2006, when scientists paid a B.C. man $850,000 for 850 grams of the meteorite that he found on Tagish Lake. Now the rock is in the spotlight again, providing what scientists say are important new clues about the building blocks of life and how they formed in the early universe more than 4.6 billion years ago. Read more
Clues to origin of life revealed in Tagish Lake meteorite New research into a meteorite that crashed into northern British Columbia nine years ago is revealing startling clues that could help unravel the origins of life on Earth. Parts of the Tagish Lake meteorite were found on a frozen lake near the Yukon border in January, 2000, after it fell to Earth in a spectacular blue-green fireball that was seen for hundreds of kilometres.
The BBC news has just reported that the meteorite contains an unusually high level of formic acid compared to other meteorites. Thats interesting! Formic acid is an organic compound, a carbon-based acid (formula CH2O2). It also can be used to convert uracil to thymine. These are nucleobases in RNA and DNA, respectively, and its possible formic acid helped along the RNA molecules used by life in a primitive Earth to become DNA. I dont know how likely that is, but its interesting. Read more
Formic acid, a molecule implicated in the origins of life, has been found at record levels on a meteorite that fell into a Canadian lake in 2000. Cold temperatures on Tagish Lake prevented the volatile chemical from dissipating quickly. An analysis showed four times more formic acid in the fragments than has been recorded on previous meteorites. The researchers told a meeting of the American Geophysical Union that the formic acid was extraterrestrial.
Keiko Nakamura-Messenger and colleagues at the NASA Johnson Space Centre in Houston, Texas, studied minute globules of organic material in the Tagish Lake carbonaceous chondrite. This meteorite was collected soon after it fell, so is fresh and likely to be uncontaminated with terrestrial organic compounds. Using microanalytical techniques the NASA team found that the globules had hydrogen and nitrogen isotopic compositions consistent with chemical reactions at strikingly frigid temperatures, only 10 to 20 K (-253 to -263 C). Temperatures that low occur in cold, interstellar molecular clouds like the one that collapsed to form the Solar System or in the outermost part of the disk surrounding the Sun when it was forming. These organic globules might represent the type of prebiotic carbon compounds that were delivered to young Earth.
A meteorite that crashed in northwest Canada almost seven years ago might have been able to host the very earliest life forms, according to NASA researchers, which opens the door to the possibility that life could be present elsewhere in the universe.
Meteorites rich in carbon and water fall to Earth once or twice every few decades. But when a truck-size meteorite crashed on frozen Tagish Lake in western Canada in 2000, researchers received a specimen speckled with stardust that promised to offer clues about the chemistry of our early solar system. Now NASA space scientists have isolated organic matter from the Tagish Lake meteorite that is at least as old as the solar system. Such ancient bodies may have delivered the raw materials for life on Earth.