American spacecraft sampling asteroid for a comeback


Cape Canaveral, Fla. (AP) – After nearly two years orbiting an ancient asteroid hundreds of miles away, this week a NASA spacecraft will attempt to land on a treacherous, boulder-filled surface and snatch a handful of debris.

The drama unfolded on Tuesday as the US takes its first crack at collecting samples of the asteroid to return to Earth, a feat only accomplished by Japan so far.

With names inspired by Egyptian mythology, the Osiris-Rex mission is looking to bring back at least 2 ounces (60 grams) of the asteroid Bennu, the largest oddly hauled beyond the moon.

The van-shaped spacecraft is aiming for a relatively flat middle of a tennis court-shaped crater called the Nightingale – compared to some parking spots here on Earth. Boulders as large 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 in, about the challenge of navigating Osari-Rex 200 million miles to one of these places Think, ”said NASA Deputy Project Manager Mike Morrow.

Once it goes out of its half-mile (0.75-kilometer-high) orbit around Bennu, the spacecraft will take four hours to go down, just above the surface.

The action increases when Osiris-Rex’s 11-foot (3.4-m) hand reaches and touches Benue. The contact should last for five to 10 seconds, just shoot long-pressurized nitrogen gas and suck the churned dirt and gravel. Already programmed, the spacecraft will operate autonomously during unprecedented touch-and-go maneuvers. With 18 minutes of lag in radio communications by all means, ground controllers cannot intervene for the spacecraft builder Lockheed Martin near Denver.

If the first attempt does not work, Osiris-Rex can try again. No collected specimens will reach Earth until 2023.

Although NASA has recovered comet dust and solar wind particles, it has so far not attempted to sample one of the nearly 1 million known asteroids in our solar system. Japan, meanwhile, expects to receive samples from the asteroid Ryugu in December – the most in milligram 10 years after bringing the specks back from the asteroid Itokawa.

Benue is an asteroid picker’s paradise.

The space rock — larger, black, round, carbon-rich than New York’s Empire State Building — was taller when our solar system was being built 4.5 billion years ago. Scientists consider it a time capsule filled with ancient building blocks that may help explain how life was formed on Earth and possibly elsewhere.

“It’s all about understanding our origins,” said Dante Lauretta of the University of Arizona, the mission’s lead scientist.

There are also selfish reasons to know Benue better.

The solar-orbiting asteroid, which swings from the Earth every six years, may take our aim late in the next century. NASA puts an impact odds of 1-2,700. The more scientists know about possible asteroids like Bennu, the safer Earth will be.

When Osiris-Rex exploded on a $ 800 million mission in 2016, scientists envisioned sandy stretches in Renu. The spacecraft was therefore designed to ingest pebbles smaller than an inch (2 cm).

When the spacecraft arrived in 2018, scientists were stunned by heavy rocks and chunky gravel everywhere. And Pebble sometimes appeared to shoot from the asteroid, falling back and sometimes closing in a cosmic game of ping-pong.

With very bumpy terrain, engineers were aiming for a tighter space than originally anticipated. The main target, the Nightingale Crater, appears to have the greatest abundance of fine grain, but the boulders are still hanging, including a dubbed Mount Doom.

Then hit COVID-19.

The team lagged behind and competed for the second and final touch-and-go dress rehearsal for the spacecraft for August. That pushed the sample grab for October.

“It’s hard to return a specimen,” said Thomas Zurbuchen, head of NASA’s science mission. “COVID made it even harder.”

Osiris-Rex has three bottles of nitrogen gas, which means it can touch three times – no more.

The spacecraft will automatically retreat if it encounters unexpected dangers such as large rocks that can cause it to take over. And there is a chance that it will touch the bottom safely, but fails to collect enough debris.

In either case, the spacecraft will orbit around Bennu and try again at another location in January.

Here at the end with the first try, Lauretta is worried, nervous, excited “and confident that we have done everything possible to ensure a safe sample.”

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The Associated Press Department of Health and Sciences has support from the Science Education Department of Howard Hughes Medical Institute. AP is solely responsible for all content.

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