![]() ![]() (Update: After further observations, 2023 DW was removed from the list of potential impacts on March 20.) If the case of 2023 DW plays out the way all previous asteroid scares have gone over the course of nearly 20 years, further observations will reduce the risk to zero. ![]() The risk assessment doesn’t have as much to do with the probabilistic roll of the cosmic dice than it does with the uncertainty that’s associated with a limited set of astronomical observations. But despite a NASA advisory and the resulting scary headlines, there’s no need to put an asteroid doomsday on your day planner for that date. Information on near-Earth asteroids came from CNEOS.A newly discovered asteroid called 2023 DW has generated quite a buzz over the past week, due to an estimated 1-in-670 chance of impact on Valentine’s Day 2046. NEOWISE and Surveyor information came from Amy Mainzer of the Lunar and Planetary Laboratory at the University of Arizona. ![]() Most information and visual reference material for the DART mission and its equipment came from NASA, the Jet Propulsion Laboratory at the California Institute of Technology and the Johns Hopkins Applied Physics Lab. “This,” he said, “is just a start.” About this story What it discovers will help planetary defense experts figure out how the deflection technique can be refined, and perhaps they will gain some insight into what other methods might work as well.įuture techniques might include using gravity to tug asteroids out of orbit, zapping them with lasers, or even moving them with tractor beams, said NASA planetary defense officer Lindley Johnson before DART launched last year. In 2024, the European Space Agency will launch a spacecraft named Hera to visit Dimorphos and investigate the crater that was left by DART. It is the size of something people would definitely want to redirect if it were headed toward Earth. It is probably chondrite, Chabot said, a common type of asteroid made of rock and metal rubble left over from when planets were formed 4.5 billion years ago. The moonlet Dimorphos seemed to be an ideal target because of its ordinary composition and extraordinary location close enough - but not too close - to Earth. “The two together will get us to 90 percent very quickly,” Chodas said. ![]() Like its predecessor NEOWISE, it will detect heat signatures rather than visible light.Īmy Mainzer, principal investigator on the Surveyor team, said it should be able to spot a 460-foot asteroid from at least 50 million miles away.Īround the same time, a new ground telescope in Chile is expected to become operational with a massive 28-foot mirror that will be able to detect objects that are much fainter and farther away than any current ground telescope. In 2026, NASA plans to launch a very sensitive infrared telescope called NEO Surveyor, which will have a wide view of the skies from a stable vantage point about a million miles up between the Earth and the sun. The truck-size rock that caused a fireball and shock wave over Russia in 2013 arrived with no warning because it came from the direction of the sun, a huge blind spot for existing telescopes.įortunately, more high-powered eyes are on the way. Others may lurk on the opposite side of the sun. Some are made of dark material that doesn’t reflect much light, making it difficult for ground-based telescopes to detect them. Some may be in orbits that don’t often bring them close to Earth. “Some asteroids are sneaky, and they have orbits that make an asteroid very hard to find,” Chodas said. That is well below NASA’s goal of identifying at least 90 percent. Models estimate that we have found just 40 percent of those that are 460 feet wide (140 meters) and larger, such as Didymos and its moonlet. Asteroids that are just a bit smaller but still large enough do a lot of regional damage are tougher to detect with current technology. ![]()
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