![]() This entry was posted in News, Space and tagged asteroid, Bennu on Augby Mihai Andrei. The study has been published in the journal Icarus. In the meantime, NASA is also testing our asteroid planetary defense systems: in November, it will launch the first mission to see if a spacecraft can deflect a space rock and change its trajectory - a technology that could become useful should asteroids like Bennu actually hurdle their way towards Earth. The recently approved Near-Earth Object Surveyor Mission is expected to help us find the others. However, we’ve only discovered half of the potentially hazardous asteroids NASA expects to find in our solar system. Bennu will pose no danger at that time, but Earth’s gravity will alter the asteroid’s path around the sun and affect its possibility of coming back and going splat. The researchers have published their predictions in the journal Icarus, and they say the asteroid will make a close approach to Earth in 2135. An image showing Bennu’s boulder-covered surface. Scientists fine-tune odds of asteroid Bennu hitting Earth through 2300 with NASA. When they put everything together, they concluded that the asteroid has a 1 in 1,750 chance of impacting Earth through 2300 - so there’s no particular reason for concern, the researchers say. This textbook presents a simulation-based approach to probability. They included the gravitational effect of not just the sun, the planets, and their satellites, but also the gravitational pull of tiny asteroids and the drag caused by interplanetary dust. Using new data from the OSIRIS-REx mission and integrating it with existing data on Bennu’s trajectory, researchers have predicted its path with unprecedented accuracy. But the odds of this happening are still very low. If it were to hit the Earth, Bennu would produce a crater around 6 miles wide, devastating everything some 600 miles around it. Still, even though it’s not the biggest or toughest asteroid out there, if Bennu were to hit the Earth, it could cause quite a lot of damage. Bennu is a “rubble pile” asteroid - it’s not made of one single rock (or monolith), but rather consists of numerous bits that have coalesced under the influence of gravity. Discovered in 1999, Bennu has a mean diameter of 490 m (1,610 ft) and was studied extensively using telescopes. NASA considers Bennu and another asteroid called 1950 DA to be the most hazardous asteroids in our solar system. With the orbit data and the sample obtained directly from the asteroid (which is currently heading back to Earth and will arrive in September 2023), we can understand Bennu better than ever before. NASA’s OSIRIS-REx mission spent more than two years orbiting Bennu, and then landing a probe on it. A mosaic image of Bennu compiled from 12 photos from the OSIRIS-REx mission. This shouldn’t keep you up at night though: there’s still a 99.94% probability that Bennu won’t hit Earth. “The Yarkovsky effect will act on all asteroids of all sizes, and while it has been measured for a small fraction of the asteroid population from afar, OSIRIS-REx gave us the first opportunity to measure it in detail as Bennu traveled around the Sun,” explained Steve Chesley, co-author of the paper and a senior research scientist at JPL.Using more precise calculations of the asteroid’s trajectory, NASA updated the likelihood of Bennu hitting Earth within the next 300 years, and it’s a bit higher than the initial estimate. NASA has a good explanation of the Yarkovsky effect and its impact on Bennu traveling through gravitational keyholes in the video below. Yarkovsky effect measurements from the OSIRIS-REx probe were thus used to fine-tune Bennu's trajectory. The effects are minuscule though can adjust Bennu’s motion over long-enough periods of time. The heat is then radiated back into space as it cools down, releasing infrared energy that generates a small push on the asteroid. As Bennu spins, the side of its body facing the Sun absorbs heat and rotates away. We know there are a lot of, er, distractions right now but NASA's got some sweet video of its asteroid rubble raiserĪlthough the researchers had a good idea of the asteroid’s path, it can be nudged by something called the Yarkovsky effect. ![]() ![]() We got it! Japanese space agency confirms its probe has Ryugu asteroid samples.NASA trying to stuff excess baggage into OSIRIS-REx after too-successful asteroid scoop.NASA's first asteroid sample on its way to Earth after OSIRIS-REx boosts for home.The team had to model the gravitational interactions between the asteroid and the Sun, and other planets and their satellites, as well as more than 300 other space rocks, and pressure from the solar wind. There are multiple factors to consider when trying to map its path as it travels through the Solar System. OSIRIS-REx has provided scientists with the most accurate data yet on Bennu’s size, shape, mass, spin, chemical composition, and orbital motion.
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