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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

NATIONAL CITY, Calif. (KGTV) - Two National City elementary schools were evacuated Monday morning due to a strong smell of gas fumes, leading parents to pick up their children at different campuses.The emergency call was reported about 9 a.m. at El Toyon Elementary at 2000 Division St. and Rancho de la Nación at 1830 Division St.National City Police and SDG&E evaluated the scenes and determined the odor was coming from a routine bleed to the gas lines. The children were not in any danger and there was no emergency, according to police.More than 1,000 students and staff members had already been evacuated to the Wrigley’s grocery store shopping plaza. They were bussed from that location to other schools.El Toyon students were rerouted to Lincoln Acres Elementary, 2200 S. Lanoitan, and Rancho de la Nación students were taken to Ira Harbison Elementary, 3235 E. 8th St.Parents can pick up their children at the campuses. 945

Move over, "The Bachelor." The royal wedding of Prince Harry and Meghan Markle — now the duke and duchess of Sussex — was a huge ratings draw.In the US, about 29 million people tuned in on Saturday morning, according to Nielsen's total of the 15 channels that showed the wedding.Some viewers awoke at 4 or 5 a.m. ET to watch the arrivals. But the ceremony officially started at 7 a.m., so that's what the 29 million figure measures.Between 6 and 9 a.m. ET, including the arrivals and the procession afterward, NBC averaged 6.4 million viewers, ABC averaged 6.3 million, and CBS had 4.8 million. On cable, Fox News had 1.9 million, CNN had 1.8 million and MSNBC had 1 million viewers.In the UK, the ratings were higher for Prince William and Kate Middleton's wedding in 2011.Those nuptials averaged 24 million viewers there, while Saturday's festivities averaged 18 million viewers.Still, it was "by far the biggest television event of the year" in the UK, The Guardian reported.The UK has a total population of about 66 million.The US has five times the population. Markle is an American woman who married a prince, so it makes sense that this wedding stirred more interest in the US.William and Kate's wedding in 2011 started a little earlier in the morning, on a weekday, and averaged 22.8 million viewers in the U.S.Nielsen said the official average for Harry and Meghan was 29.2 million, but that only counts people watching on TV at home. An unknown number streamed the wedding on mobile devices.There was strong interest later in the day, as well. Cable news ratings remained high all day long. CNN rebroadcast the wedding in prime time and averaged 1.6 million viewers, out-rating Fox and MSNBC. 1725

MOUNT PLEASANT, Iowa (AP) — A prosecutor in the trial of an Iowa father whose infant son was found dead and maggot-infested in a baby swing last year has told a jury the child "died of diaper rash."Assistant Iowa Attorney General Coleman McAllister told jurors Tuesday that 4-month-old Sterling Koehn had been in the same diaper for nine to 14 days when his body was found in the swing Aug. 30, 2017, at his parents' Alta Vista apartment, the Courier reported .The baby's father, 29-year-old Zachary Paul Koehn, is charged with murder and child endangerment. The boy's mother, Cheyanne Harris, is also charged and faces a separate trial at a later date.McAllister said Tuesday in opening statements that the baby's heavily soiled diaper had attracted bugs that had laid eggs, which had hatched into maggots. The resulting diaper rash led to ruptured skin, and e.Coli bacteria set in."He died of diaper rash. That's right, diaper rash," McAllister said.A coroner's report showed the baby died of malnutrition, dehydration and the infection.In opening statements Tuesday, Koehn's attorney said the baby's death was a tragedy, but not a crime.McAllister denied the defense's claims, saying Koehn was an experienced parent. He noted that Koehn's 2-year-old daughter was also in the apartment and was healthy, and that Koehn had money to buy food and baby supplies. He stated Koehn was a drug user.Nurse and county rescue squad EMT Toni Friedrich testified Tuesday that she was the first to arrive at the apartment after Koehn called 911 to report the baby had died. Friedrich said Koehn showed no emotion when he led her to the dark, hot bedroom where the baby's body was.The baby's "eyes were open, and it was a blank stare," she said.Friedrich said when she touched the baby's chest, his clothing was crusty. When she moved his blanket, gnats flew up, she said.Koehn's trial was moved from Chickasaw County to Henry County to counter pretrial publicity. 1969

Nearly 800 nurses were on a picket line Tuesday in Pennsylvania. The nurses work at St. Mary Medical Center in Langhorne, near Philadelphia, and they say they are walking off the job to fight for their patients.At issue is the hospital’s contract with the nurse’s union. The nurses want a new contract with higher wages and safeguards for patient safety.The nurses say they are caring for more patients during the coronavirus pandemic than they should, and that is putting patients at risk.“Safe staffing is the main issue in our negotiation--it's why we organized last year in the first place,” says Kathy McKamey R.N., who works on St Mary's MG2 unit and has been at the hospital for 10 years, said in a statement provided by the union.The hospital’s owner, Trinity Health, said the union rejected a contract last week that included higher wages.Hospitals in the Philadelphia area told the Philadelphia Inquirer that they would hire replacement nurses to work if the union goes on strike."We respect the union members’ right to strike, and we remain committed to negotiating in good faith to reach agreement on a fair, consistent and sustainable initial contract for St. Mary nurses. We look forward to the day productive negotiations can resume," said a statement from Trinity Health.The nurses say their strike will continue Wednesday if necessary. 1360

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