Subtitles section Play video Print subtitles { ♪INTRO } One of the hardest parts of astronomy is figuring out causes and effects. After all, just because it seems like two things are related doesn't necessarily mean they are. But last week, a team of radio astronomers presented one of those rare “smoking gun” pictures at a meeting of the American Astronomical Society's High Energy Astrophysics Division. It shows a so-called cannonball pulsar blasting away from a nearby supernova, and a trail of energized gas clearly points to where it came from. Pulsars are the rapidly-spinning cores of neutron stars, which are stars mostly made of neutrons. But this thing isn't just spinning fast: It's also traveling in a straight line at more than a /million/ kilometers per hour. This pulsar is named J0002+6216 — which I swear is not a random string of numbers that I made up, it's actually describing the coordinates, so is useful for astronomers. Regardless, it was discovered as part of a really cool project called Einstein@Home. Instead of using a single supercomputer to comb through telescope data, this project uses computer power donated by hundreds of thousands of citizen scientists. It's specifically searching for pulsars, and so far, it's been pretty successful. For this new discovery, researchers used the equivalent of 10,000 years of computing time to search observations made by NASA's Fermi Gamma-ray Space Telescope. They discovered 23 pulsars, but J0002 really caught their eye. This object is about 6500 light-years from Earth, and it spins 8.7 times every second. But what was really significant was its speed. This thing moves through space at around 4 million kilometers per hour, which is faster than 99% of measured pulsars. Follow-up observations with the ground-based Very Large Array also revealed that it has a dramatic, 13 light-year-long tail, caused by a shockwave that forms as the super-speed object blasts through nearby gas. Yes, I said 13 light-years. Scientists think this object was formed thanks to a supernova. Based on the size of the bubble of material that the supernova left behind, called a supernova remnant, the team estimates the explosion happened around 10,000 years ago. It crushed the dying star's core into a pulsar and then gave it a kick in one direction. At first, the light, outer layers of the star were likely blasted away much faster than the pulsar, but as everything slammed into the gas and dust surrounding the supernova, that light material also quickly lost its momentum. Think about a cannon firing: The first stuff to come out is fire and smoke, but the heavy cannonball eventually goes the farthest. In the case of J0002, the astronomers estimate it overtook the supernova remnant after about 5000 years. And today, it appears about 53 light-years from the bubble's center. Still, that doesn't explain how this thing ended up moving so fast. And that's… well, it's still kind of a mystery. After all, if a spherical star explodes, you'd think it would be relatively symmetric. So it would make sense that forces pushing on the star's core should mostly cancel out. But clearly, that's not what happened. This means J0002 is going to be a really useful object — especially since scientists have been able to figure out so much about its behavior. So as we keep studying it, it could provide valuable new data to solve the riddle. Also, it just looks really darn cool. Changing gears to something much, much smaller, another team of researchers announced last week that they've successfully tested a new tool to fight against bacteria in space. The paper was published in the journal Frontiers in Microbiology, and it described a new material tested onboard the International Space Station that dramatically reduced the population of potentially-harmful microbes. Bacteria are a big problem in space for many reasons. For one, to keep the air in and space out, all spacecraft are closed systems, meaning that every time an astronaut sneezes, that sneeze is just… there. Our immune systems can also get weaker under the stresses of spaceflight, making it harder for our bodies to fight off an infection. And to top it all off, microbes can actually get stronger in microgravity and can mutate even faster. This is why NASA sterilizes almost everything that goes to space, from new equipment to some of the food astronauts eat. But since you can't exactly sterilize the astronauts themselves, there's no way to keep bacteria totally out. Scientists have even found so-called superbugs up there, which are microbes resistant to many kinds of antibiotics. And that's where this new paper comes in. Researchers created a new material, called AGXX, that combines the elements silver and ruthenium. Then, they took their mixture, coated a few pieces of steel, and stuck the pieces on a spot you might expect to be dirty: the bathroom door! The test had three parts: an uncoated patch of plain steel, a region covered in a coating of pure silver, and an area with AGXX. After 19 months, the silver-only part showed 30% fewer bacteria than the steel region, while the area covered by AGXX had a whopping 80% reduction. That kind of reduction could be important for long-term spaceflight, like what it would take to send a crew to Mars and keep them healthy while they're there. It's not surprising that silver is a key ingredient in this stuff: We've known about the metal's antibacterial properties for thousands of years, and modern medicine uses it in things like bandages for burn victims. Ruthenium, on the other hand, is one of our newest attempts to fight bacteria. It's not used by itself, though; instead, its antimicrobial properties seem to come in combination with other elements. But here's the thing: Scientists don't really know why these metals work. They seem to be able to bind with a bacteria's DNA and disrupt its basic functions, but why that's so effective isn't really understood. And, like with that mysteriously-fast pulsar, this puzzle makes any new data worth its weight in… ruthenium, I guess. Which probably is more expensive than gold? I'm just guessing, cause I don't hear about it very much. Thanks for watching this episode of SciShow Space News! 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B2 pulsar supernova bacteria space silver scishow Spotted: One of the Fastest Pulsars Ever Seen | SciShow News 2 0 林宜悉 posted on 2020/03/30 More Share Save Report Video vocabulary