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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

Amazon's search for the perfect home for its next headquarters could be leaning towards larger cities.Executives have visited some of the bigger names on the list of 20 finalists in recent months, according to a report in the Wall Street Journal. They dropped in on New York City, Miami, Chicago and Newark, while possibly ghosting smaller or more suburban ares like Raleigh, North Carolina, and Montgomery County, Maryland.Amazon may have decided that a city is necessary for luring the best employees."The key for Amazon is that they want to build a second HQ that is an attractive place to live and work for young professionals. This is why quality of life in the city will matter," said Nathan Jensen, a professor of government at the University of Texas at Austin.Other than both being finalists for HQ2, places like Miami and Montgomery County don't have much in common. Miami is a cosmopolitan city that draws business and tourists from around the world. Montgomery County, located outside of Washington D.C. is less well known and lacks some of the splashier attractions of a warm city perched on the beach.Not getting Amazon could be a mixed blessing for the less urban locations. Absorbing up to 50,000 new workers would be a major undertaking, notes Jensen. And many of those would be high-wage positions, which could recreate some of the issues with soaring housing costs, income inequality and gentrification seen in Amazon's home base, Seattle, as well as other regions with major tech companies.The issues wouldn't be insurmountable."Unlike an unplanned expansion of the workforce, cities do have the ability to plan for this. This has been one of my disappointments in not seeing most cities HQ2 proposals. This is exactly the time when we, as a community, can thinking solutions to these challenges," said Jensen.Amazon has searched for a home for its second headquarters — nicknamed HQ2 — for more than a year. The company has whipped up suspense around the decision. It has cities competing with glossy proposals and tax cuts and Amazon watchers are eagerly looking for clues, and odds-makers are aking bets.The new facility would create 50,000 jobs and cost billion to build. After the company received 238 proposals, it selected 20 finalists cities and metropolitan areas in January. Amazon has said it will announce the winning city by end of the year. 2405

After repeated calls for him to do so, Mark Zuckerberg has decided he will testify before Congress.Facebook sources tell CNNMoney the 33-year-old CEO has come to terms with the fact that he will have to testify before Congress within a matter of weeks, and Facebook is currently planning the strategy for his testimony.The pressure from lawmakers, the media and the public has become too intense to justify anything less.The Facebook sources believe Zuckerberg's willingness to testify will also put pressure on Google CEO Sundar Pichai and Twitter CEO Jack Dorsey to do the same. Senate Judiciary Chairman Chuck Grassley has officially invited all three CEOs to a hearing on data privacy on April 10. 709

A website tracking early voting numbers reports more than 23,500,000 votes have been cast in the 2020 presidential election as of Friday night.The US Election Project, run by Professor Michael McDonald at the University of Florida for the last few elections, is keeping track of early voting, mail-in and absentee ballot data states make available. The details of those ballots are not shared, these are just the raw numbers of how many ballots have been cast.The site is also tracking each state’s ballots cast as compared to the entire number of votes counted in the 2016 election. For the country as a whole, the more than 23.5 million ballots cast is about 17 percent of the total number of votes in the 2016 election. Some states appear to be on track to potentially reach their 2016 voter turnout number, or get very close, before the election.In Vermont, more than 136,000 ballots have been cast, that’s more than 42 percent of the total number of ballots cast in the 2016 election.In Texas, early voting started Tuesday and already more than 2,647,000 ballots have been cast. That’s almost 30 percent of the total number of ballots cast in 2016.Professor McDonald does track about a dozen states that report party affiliation of the ballots returned. Those numbers show a higher number of Democrats have returned their ballots compared to those identified as Republican. However, there is no way to tell who those ballots voted for exactly, and history shows Democrats typically have higher numbers of mail-in ballots, according to McDonald. 1557

Although a school resource officer did fire at the teen who'd shot two fellow students at a Maryland high school last week, the shooter died of a bullet from his own gun, authorities say.Austin Wyatt Rollins -- a 17-year-old who killed one student and injured another -- shot himself in the head in a hallway at Great Mills High School on the morning of March 20, right as school resource officer Blaine Gaskill fired his gun at him, the St. Mary's County Sheriff's Office said.The officer's shot struck Rollins' gun, which was in the teen's hand, the sheriff's office said. 582

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