After circling an ancient asteroid hundreds of millions of miles away for almost two years, 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. NASA Plans to Land First Woman on the Moon in 2024Lunar landing will be America’s first since 1972The 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 $800 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.”
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Day: October 18, 2020
Johns Hopkins Coronavirus Resource Center reported early Sunday that there are nearly 39.7 million COVID-19 infections worldwide and 1.1 million deaths from the virus.The U.S. continues to lead the world in COVID cases, with 8.1 million infections.India said Sunday it had recorded more than 61,000 COVID-19 cases in the previous 24-hour period. India has almost 7.5 million COVID-19 cases, with more than 114,000 deaths, according to Johns Hopkins statistics.Paris streets were deserted Saturday night as the city began a 9 p.m. to 6 a.m. curfew, designed to help curb the spread of the coronavirus.At least seven other French cities, including Lyon, Grenoble, Aix-en-Provence, Montpellier, Lille, Rouen and Saint-Étienne are also under the nighttime curfew, scheduled to be in place for four weeks.Belgium will be placed under a midnight to 5 a.m. nationwide curfew Monday to combat the country’s rising COVID-19 caseload. In addition, Belgium has ordered all cafes, bars, and restaurants shuttered, starting Monday.Two European foreign ministers — Austria’s Alexander Schallenberg and Belgium’s Sophie Wilmès — have been infected with the coronavirus. Both attended a European Union meeting in Luxembourg on Monday.The Dutch king and queen cut their vacation to Greece short amid criticism that they were doing the opposite of what the Dutch people have been advised to do during the pandemic – stay home as much as possible to flatten the spread of the virus.King Willem-Alexander and Queen Maxima left The Hague on Friday but returned Saturday.”We do not want to leave any doubts about it: in order to get the COVID-19 virus under control, it is necessary that the guidelines are followed,” the couple said in a royal statement. “The debate over our holiday does not contribute to that.”
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Johns Hopkins Coronavirus Resource Center reported early Sunday that there are nearly 39.7 million COVID-19 infections worldwide and 1.1 million deaths from the virus.The U.S. continues to lead the world in COVID cases, with 8.1 million infections.India said Sunday it had recorded more than 61,000 COVID-19 cases in the previous 24-hour period. India has almost 7.5 million COVID-19 cases, with more than 114,000 deaths, according to Johns Hopkins statistics.Paris streets were deserted Saturday night as the city began a 9 p.m. to 6 a.m. curfew, designed to help curb the spread of the coronavirus.At least seven other French cities, including Lyon, Grenoble, Aix-en-Provence, Montpellier, Lille, Rouen and Saint-Étienne are also under the nighttime curfew, scheduled to be in place for four weeks.Belgium will be placed under a midnight to 5 a.m. nationwide curfew Monday to combat the country’s rising COVID-19 caseload. In addition, Belgium has ordered all cafes, bars, and restaurants shuttered, starting Monday.Two European foreign ministers — Austria’s Alexander Schallenberg and Belgium’s Sophie Wilmès — have been infected with the coronavirus. Both attended a European Union meeting in Luxembourg on Monday.The Dutch king and queen cut their vacation to Greece short amid criticism that they were doing the opposite of what the Dutch people have been advised to do during the pandemic – stay home as much as possible to flatten the spread of the virus.King Willem-Alexander and Queen Maxima left The Hague on Friday but returned Saturday.”We do not want to leave any doubts about it: in order to get the COVID-19 virus under control, it is necessary that the guidelines are followed,” the couple said in a royal statement. “The debate over our holiday does not contribute to that.”
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