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After almost two years circling an ancient asteroid hundreds of millions of miles away, a NASA spacecraft this week will attempt to descend to the treacherous, boulder-packed surface and snatch a handful of rubble.The drama unfolds Tuesday as the U.S. takes its first crack at collecting asteroid samples for return to Earth, a feat accomplished so far only by Japan.Brimming with names inspired by Egyptian mythology, the Osiris-Rex mission is looking to bring back at least 2 ounces (60 grams) worth of asteroid Bennu, the biggest otherworldly haul from beyond the moon.The van-sized spacecraft is aiming for the relatively flat middle of a tennis court-sized crater named Nightingale — a spot comparable to a few parking places here on Earth. Boulders as big as buildings loom over the targeted touchdown zone.“So for some perspective, the next time you park your car in front of your house or in front of a coffee shop and walk inside, think about the challenge of navigating Osiris-Rex into one of these spots from 200 million miles away,” said NASA’s deputy project manager Mike Moreau.Once it drops out of its half-mile-high (0.75 kilometer-high) orbit around Bennu, the spacecraft will take a deliberate four hours to make it all the way down, to just above the surface.Then the action cranks up when Osiris-Rex’s 11-foot (3.4-meter) arm reaches out and touches Bennu. Contact should last five to 10 seconds, just long enough to shoot out pressurized nitrogen gas and suck up the churned dirt and gravel. Programmed in advance, the spacecraft will operate autonomously during the unprecedented touch-and-go maneuver. With an 18-minute lag in radio communication each way, ground controllers for spacecraft builder Lockheed Martin near Denver can’t intervene.If the first attempt doesn’t work, Osiris-Rex can try again. Any collected samples won’t reach Earth until 2023.While NASA has brought back comet dust and solar wind particles, it’s never attempted to sample one of the nearly 1 million known asteroids lurking in our solar system until now. Japan, meanwhile, expects to get samples from asteroid Ryugu in December — in the milligrams at most — 10 years after bringing back specks from asteroid Itokawa.Bennu is an asteroid picker’s paradise.The big, black, roundish, carbon-rich space rock — taller than New York’s Empire State Building — was around when our solar system was forming 4.5 billion years ago. Scientists consider it a time capsule full of pristine building blocks that could help explain how life formed on Earth and possibly elsewhere.“This is all about understanding our origins,” said the mission’s principal scientist, Dante Lauretta of the University of Arizona.There also are selfish reasons for getting to know Bennu better.The solar-orbiting asteroid, which swings by Earth every six years, could take aim at us late in the next century. NASA puts the odds of an impact at 1-in-2,700. The more scientists know about potentially menacing asteroids like Bennu, the safer Earth will be.When Osiris-Rex blasted off in 2016 on the more than 0 million mission, scientists envisioned sandy stretches at Bennu. So the spacecraft was designed to ingest small pebbles less than an inch (2 centimeters) across.Scientists were stunned to find massive rocks and chunky gravel all over the place when the spacecraft arrived in 2018. And pebbles were occasionally seen shooting off the asteroid, falling back and sometimes ricocheting off again in a cosmic game of ping-pong.With so much rough terrain, engineers scrambled to aim for a tighter spot than originally anticipated. Nightingale Crater, the prime target, appears to have the biggest abundance of fine grains, but boulders still abound, including one dubbed Mount Doom.Then COVID-19 struck.The team fell behind and bumped the second and final touch-and-go dress rehearsal for the spacecraft to August. That pushed the sample grab to October.“Returning a sample is hard,” said NASA’s science mission chief, Thomas Zurbuchen. “The COVID made it even harder.”Osiris-Rex has three bottles of nitrogen gas, which means it can touch down three times — no more.The spacecraft automatically will back away if it encounters unexpected hazards like big rocks that could cause it to tip over. And there’s a chance it will touch down safely, but fail to collect enough rubble.In either case, the spacecraft would return to orbit around Bennu and try again in January at another location.With the first try finally here, Lauretta is worried, nervous, excited “and confident we have done everything possible to ensure a safe sampling.”___The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content. 4807

ALPINE (CNS) - A 7-year old tiger at Alpine's Lions Tigers & Bears animal rescue facility died of injuries inflicted by a fellow tiger, it was announced Tuesday.Maverick suffered fatal injuries after he and the other tiger -- Moka - - were accidentally allowed to come into contact with one another on Monday. The animals were living in separate enclosures, according to Lions Tigers & Bears founder Bobbi Brink, who said no staff or visitors were harmed.The staff veterinarian assessed both animals afterward. Moka has scratches, but no serious injuries."This was a human error, and one we're so deeply heartbroken about," Brink said. "When caring for a 400-plus-pound apex predator, layered safety measures must be established, and this is exactly what we've implemented at our accredited sanctuary since our founding."Unfortunately, one of our safety measures was mistakenly missed, and because these magnificent, massive animals are wild, their reactions to their surroundings -- especially new situations -- are unpredictable," she said.According to Brink, the nonprofit organization regularly conducts staff safety trainings, including one on emergency protocols last weekend. She said the protocols will be reviewed extensively this week.Maverick was rescued on April 20, 2014, at 9 months old. He was born in captivity and purchased illegally by someone who did not have the proper licensing to own an exotic animal. California Fish & Wildlife personnel seized Maverick and reached out to Lions Tigers & Bears to provide him with a home."There is an inherent risk when keeping apex predators in captivity, and we would like nothing more than to see an end to this, but until then, and as long as our sanctuary is needed, we will continue to be there for these animals in need," Brink said. "Maverick, we will miss your friendly chuffs and curious, fun-loving spirit. Rest easy our sweet boy, run free, and keep on swimming." 1956

After 22 seasons in the NBA, Vince Carter is retiring.Carter announced his retirement on Thursday during his podcast "Winging it with Vince Carter."The announcement was largely a formality because the 43-year-old Carter had said many times over the course of the season that this would be his last in the NBA. 317

Amazon is going to Middle Earth.The streaming service on Monday announced it is bringing J.R.R. Tolkien's fantasy epic to television, with a multiple season commitment.The television series will take place before the 2001 feature film "The Fellowship of the Ring," which kicked off the trilogy directed by Peter Jackson. 328

A federal appeals court on Thursday upheld a ruling blocking the Trump administration from ending the Obama-era program that protects young undocumented immigrants who came to the United States as children from being deported.The ruling from a panel of the 9th US Circuit Court of Appeals means a nationwide injunction allowing the Deferred Action for Childhood Arrivals program to continue will remain in effect.Challengers are likely to succeed in their argument that the planned phase-out is illegal, the court ruled."We conclude that plaintiffs are likely to succeed on their claim that the rescission of DACA -- at least as justified on this record -- is arbitrary, capricious, or otherwise not in accordance with law," reads the opinion from Judge Kim McLane Wardlaw, an appointee of President Bill Clinton.In September 2017, the Trump administration announced plans to phase out DACA, but lower court judges blocked the administration from doing so and ordered that renewals of protections for recipients continue until the appeals are resolved.The legality of the program is not at issue in this particular case. Instead, lower courts are examining how the administration made its decision to end DACA.Thursday's case was brought by the University of California, as well as California and a few other states.California Attorney General Xavier Becerra called the ruling a "tremendous victory" for "our young immigrant Dreamers.""This fight, of course, is far from over," he said in a statement. "We will continue to defend Dreamers and DACA all the way to the Supreme Court if necessary." 1613