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NASA's OSIRIS-REx mission and the asteroid Bennu have had a date planned for two years, and just after noon ET today, they finally got to meet face to face. OSIRIS-REx fired its thrusters for a small burn, putting it about 4.3 miles from Bennu, marking the end of its journey to the asteroid.The mission -- which stands for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer -- is NASA's first asteroid sample return mission. It launched in September 2016 and will spend two years up close and personal with Bennu. First images of the asteroid from the spacecraft's perspective have appeared as it got closer and closer.On Tuesday, the spacecraft will fly within 5 miles of Bennu, which will help design future orbits and map the surface.Over the next year, OSIRIS-REx will survey the asteroid using five scientific instruments on board the spacecraft. These instruments will help it determine a safe location from which to collect a small sample from Bennu's surface that will be returned to Earth in September 2023."Bennu's low gravity provides a unique challenge for the mission," said Rich Burns, OSIRIS-REx project manager at NASA's Goddard Space Flight Center. "At roughly 0.3 mile in diameter, Bennu will be the smallest object that any spacecraft has ever orbited."The sample from Bennu, a near-Earth asteroid, could help scientists understand not only more about asteroids that could impact Earth but about how planets formed and life began.OSIRIS-REx has a camera suite, a laser altimeter for 3D mapping, a thermal emission spectrometer to take temperature and mineral content and spectrometers to measure X-rays, nearly infrared and visible light.An arm mechanism called TAGSAM will reach out to collect the sample from Bennu's surface, making contact with the asteroid for five seconds in July 2020. During this contact, the arm will use a nitrogen gas burst to stir up rock and other materials on the surface so it can capture them. There is enough nitrogen for three attempts if the first is unsuccessful.NASA said the estimated 2.1-ounce sample size equates to about 30 sugar packets worth of dirt and rocks.The arm has a full range of motion, with joints capable of movement comparable to shoulder, elbow and wrist joints. It was "flexed" in space for the first time on November 14."The TAGSAM exercise is an important milestone, as the prime objective of the OSIRIS-REx mission is to return a sample of Bennu to Earth," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. "This successful test shows that, when the time comes, TAGSAM is ready to reach out and tag the asteroid."In 2021, it will be time for the spacecraft to essentially turn around and begin its two-year journey home. The sample will be packed into a capsule that will drop in the Utah desert in 2023.For two years after the return, the sample will be cataloged and analyzed. Afterward, 75% of the returned sample will remain at NASA's Johnson Space Flight Center so it can be used for more research by scientists from around the world.Why did NASA select Bennu out of the 780,000 known asteroids in our solar system?It was discovered in 1999, and scientists have been studying it ever since. The asteroid fits a number of criteria that make it intriguing and convenient.Bennu is relatively close to Earth, and its orbit even crosses that of our planet, making a close approach every six years. Though small asteroids can rotate very quickly, Bennu has a diameter just a bit bigger than the height of the Empire State Building and rotates relatively slowly, each 4.3 hours. This means OSIRIS-REx can match its velocity and touch down briefly.The asteroid could pass close to Earth, closer than the moon, in 2135, with even closer approaches possible in 2175 and 2195. A direct hit is unlikely, but the data gathered during this mission can help determine the best ways to deflect near-Earth asteroids.The asteroid is also old and well-preserved, full of valuable materials that may even contain clues about how life began. Bennu is essentially a leftover from the formation of our solar system billions of years ago, although some of the minerals inside it could be even older.This carbon-rich asteroid could be full of organic molecules, metals, platinum and even water -- the essential ingredients for life. It's because of objects like Bennu that these resources were delivered to Earth during its formation.Asteroids could even serve as fuel stations for robotic and human missions if we can unlock the hydrogen and oxygen inside them, NASA said.Bennu probably broke off of a larger asteroid in the asteroid belt between Mars and Jupiter a couple billion years ago. This knocked it through space until an orbit close to Earth locked it in place. And Bennu is believed to be a grouping of rocks held together by gravity rather than a single object.But its orbit drifts 0.18 miles each year toward the sun, and OSIRIS-REx will enable researchers to understand why and to predict Bennu's movements. This could also explain how it ended up as a near-Earth asteroid."The story of this asteroid is the story of the solar system," said Bashar Rizk, instrument scientist for OSIRIS-REx. "When we understand Bennu, we will understand something fundamental about our solar system."The-CNN-Wire 5356

MURRIETA, Calif. (KGTV) -- The contractor involved in Monday’s deadly gas explosion in Murrieta did not call 811 as required by law, according to officials. One SoCalGas worker was killed in the explosion and more than a dozen people were injured. If a homeowner or contractor plans to do any digging into the ground, there must be a call placed to 811 two working days in advance, according to state law. Investigators say a solar company was working on the Murrieta home when the explosion occurred. That company, Horizon Solar Power, would not specifically address the incident. A spokesperson told Team 10: “Yesterday, four members of our team were at the site of a residential explosion in Murrieta. We are working with authorities and collecting facts to better understand what happened. Our primary thoughts are with the people who were injured and their families, including with the family of the person who lost his life.”An SDG&E spokesperson said 811 must be called for projects including landscaping, fence, and patio projects. In San Diego County when you place that call, SDG&E will mark the location of buried utility owned pipelines and other lines. The service is free.RELATED: Utility worker's body recovered after Murrieta house explosionSDG&E receives between 12 to 13,000 Dig Alert location requests each month. Last year, utility crews were called to repair approximately 306 natural gas lines damaged due to construction or landscaping, according to a spokesperson. This year so far, there have been more than 90 preventable gas leaks. Starting July 1, 2020, the new California Underground Facilities Safe Excavation Board (Dig Safe Board) will begin enforcement, according to SDG&E. Enforcement will include anything from training classes and/or fines up to ,000. The Dig Safe Board is responsible for issue fines. 1866

NAPLES, Fla. - Two people were killed after falling 70 feet when an elevator collapsed in Naples, Florida on Wednesday. Two construction workers were standing on a lift at Club Brittany of Park Shore, the Naples Fire Department said. They working on an outside elevator when the lift the construction workers were on collapsed and dropped 70 feet, they said. It has been confirmed both workers are dead. The elevator is attached to the side of the building and is typically used during renovations."This would be used after the building is completed, probably windows, railings, repairs and stucco," said David Mola, a contractor who lives near the accident.Mola says accidents involving these elevators are extremely rare.  Construction on condominiums along Gulfshore Boulevard have ramped up since season has ended."They're usually restricted, they usually have 6 months from now to late October to finish," said Mola.Officials from OSHA, the Occupational Safety and Health Administration arrived at the scene to investigate.The identity of the victims have not been released. 1107

NBC News announced Wednesday that President Donald Trump would participate in a town hall-style event on Thursday — the day that he and Democratic presidential nominee Joe Biden were scheduled to have a debate prior to Trump's COVID-19 diagnosis.NBC says the event, hosted by Today show anchor Savannah Guthrie, will take place in Miami with "a group of Florida voters."The network also said that it had received a statement from Dr. Clifford Lane, the Clinical Director at the National Institutes of Health, who said that both he and Dr. Anthony Fauci had cleared Trump to participate.The records reportedly reviewed by Lane and Fauci included a PCR COVID-19 test. Lane said that he has a "high degree of confidence" that the president is "not shedding infectious virus."The one-hour event will begin at 8 p.m. ET Thursday.Trump's town hall will come the same day that Joe Biden will be holding his own town hall event on ABC. Biden scheduled the event last week after the second presidential debate was canceled. Trump withdrew from the debate last week after the Commission on Presidential Debates announced the second debate would be held virtually over safety concerns following Trump's illness. 1208

NASHVILLE, Tennessee — Opry Mills mall in Nashville announced plans to reopen Friday, one day after a shooting claimed the life of a 22-year-old man. The mall will reopen at 10 a.m. local time – fewer than 24 hours after a murder investigation began inside the building. There will be an enhanced Metro Nashville Police presence to ensure that shoppers and staff feel safe. The shooting happened just before 2:30 p.m. local time Thursday inside a hallway near the Auntie Anne's pretzel shop, just across from Old Navy. The victim, Demarco Churchwell, was taken to TriStar Skyline Medical Center, where he later died. Police said the gunman is 22-year-old Justin Golson. He's been charged with homicide. As soon as shots were fired, shoppers scattered, terrified after hearing those gunshots.  "I thought I was going to die, I thought I was never going to see my husband or daughter again,” one woman said. Churchwell and the alleged shooter apparently knew each other. Police said the shooting was the result of an ongoing fight between them.  1111

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