geekosystem

Space debris is fascinating, fun, and sometimes scary. The meteorite pieces that rained down on Russia’s Chelyabinsk region last month hit with the force of 30 atomic bombs, but these were not the largest we've seen or recovered. On this day in 1976, a meteor entered Earth's atmosphere, broke up, and erupted into a massive fireball over the outskirts of Jilin City in northern China. Around four metric tons of extraterrestrial rock "scattered radially in all directions."

Tomorrow the 143,000 ton asteroid 2012 DA14 will pass a mere 17,200 miles from the Earth. What does that mean for you? Nothing. There's no chance of DA14 hitting the Earth. We'll all be fine this time around, but hundreds of smaller objects strike the Earth every year. Our friends at Movoto have a handy calculator to get the odds that one will hit your house. Give it a try, and you'll probably feel a lot better about the whole thing.

It's no news that the surface of Mars was once home to water, but scientists may have just found more evidence that that same water could have once been teeming with living creatures -- or at least supported enough of them to prove we're not alone in the universe. Researchers from The Open University and the University of Leicester have found evidence in meteorites from Mars that the water on the Red Planet may once have been warm enough to support life.

NASA researchers studying meteorites have found that they contain several of the components needed to make DNA on Earth. The discovery provides support for the idea that the building blocks for DNA were likely created in space, and carried to Earth on objects, like meteorites, that crashed into the planet's surface. According to the theory, the ready-made DNA parts could have then assembled under Earth's early conditions to create the first DNA. The researchers, from NASA's Goddard Space Flight Center, found adenine and guanine -- two of the nucleobases needed to make DNA (the other two are thymine and cytosine, which were not found) -- on meteorite samples. Additionally, the samples showed the presence of three molecules that are similar to nucleobases, but do not have a biological role on Earth: Purine, 2.6-diaminopurine, and 6.8-diaminopurine. Hypoxanthine and xanthine, compounds used in biological processes, but not DNA, were also found. What is particularly significant about the new research is that the scientists were able to confirm that the biological parts were created in space and carried to Earth.

Just how cool is legendary fantasy author Sir Terry Pratchett? In early 2009, he was knighted, reportedly saying on the occasion that "you can't ask a fantasy writer not to want a knighthood. You know, for two pins I'd get myself a horse and a sword." This year, he took his new station of Knight Bachelor seriously: Pratchett took it upon himself to forge a sword using more than 175 pounds of iron ore found in a deposit near his home in Wiltshire. For good measure, he added several chunks of meteorite -- "thunderbolt iron" for their "highly magical" properties: "you’ve got to chuck that stuff in whether you believe in it or not."