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, reports AP.
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 $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.”
Instead of a cosmic rock, the newly discovered object appears to be an old rocket from a failed moon-landing mission 54 years ago that’s finally making its way back home, according to NASA’s leading asteroid expert. Observations should help nail its identity.
“I’m pretty jazzed about this,” Paul Chodas told The Associated Press. “It’s been a hobby of mine to find one of these and draw such a link, and I’ve been doing it for decades now.”
Chodas speculates that asteroid 2020 SO, as it is formally known, is actually the Centaur upper rocket stage that successfully propelled NASA’s Surveyor 2 lander to the moon in 1966 before it was discarded. The lander ended up crashing into the moon after one of its thrusters failed to ignite on the way there. The rocket, meanwhile, swept past the moon and into orbit around the sun as intended junk, never to be seen again — until perhaps now.
A telescope in Hawaii last month discovered the mystery object heading our way while doing a search intended to protect our planet from doomsday rocks. The object promptly was added to the International Astronomical Union’s Minor Planet Center’s tally of asteroids and comets found in our solar system, just 5,000 shy of the 1 million mark.
The object is estimated to be roughly 26 feet (8 meters) based on its brightness. That’s in the ballpark of the old Centaur, which would be less than 32 feet (10 meters) long including its engine nozzle and 10 feet (3 meters) in diameter.
What caught Chodas’ attention is that its near-circular orbit around the sun is quite similar to Earth’s — unusual for an asteroid.
“Flag number one,” said Chodas, who is director of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in Southern California.
The object is also in the same plane as Earth, not tilted above or below, another red flag. Asteroids usually zip by at odd angles. Lastly, it’s approaching Earth at 1,500 mph (2,400 kph), slow by asteroid standards.
As the object gets closer, astronomers should be able to better chart its orbit and determine how much it’s pushed around by the radiation and thermal effects of sunlight. If it’s an old Centaur — essentially a light empty can — it will move differently than a heavy space rock less susceptible to outside forces.
That’s how astronomers normally differentiate between asteroids and space junk like abandoned rocket parts, since both appear merely as moving dots in the sky. There likely are dozens of fake asteroids out there, but their motions are too imprecise or jumbled to confirm their artificial identity, said Chodas.
Sometimes it’s the other way around.
A mystery object in 1991, for example, was determined by Chodas and others to be a regular asteroid rather than debris, even though its orbit around the sun resembled Earth’s.
Even more exciting, Chodas in 2002 found what he believes was the leftover Saturn V third stage from 1969′s Apollo 12, the second moon landing by NASA astronauts. He acknowledges the evidence was circumstantial, given the object’s chaotic one-year orbit around Earth. It never was designated as an asteroid, and left Earth’s orbit in 2003.
The latest object’s route is direct and much more stable, bolstering his theory.
“I could be wrong on this. I don’t want to appear overly confident,” Chodas said. “But it’s the first time, in my view, that all the pieces fit together with an actual known launch.”
And he’s happy to note that it’s a mission that he followed in 1966, as a teenager in Canada.
Asteroid hunter Carrie Nugent of Olin College of Engineering in Needham, Massachusetts, said Chodas’ conclusion is “a good one” based on solid evidence. She’s the author of the 2017 book “Asteroid Hunters.”
“Some more data would be useful so we can know for sure,” she said in an email. “Asteroid hunters from around the world will continue to watch this object to get that data. I’m excited to see how this develops!”
The Harvard-Smithsonian Center for Astrophysics’ Jonathan McDowell noted there have been “many, many embarrassing incidents of objects in deep orbit ... getting provisional asteroid designations for a few days before it was realized they were artificial.”
It’s seldom clear-cut.
Last year, a British amateur astronomer, Nick Howes, announced that an asteroid in solar orbit was likely the abandoned lunar module from NASA’s Apollo 10, a rehearsal for the Apollo 11 moon landing. While this object is likely artificial, Chodas and others are skeptical of the connection.
Skepticism is good, Howes wrote in an email. “It hopefully will lead to more observations when it’s next in our neck of the woods” in the late 2030s.
Chodas’ latest target of interest was passed by Earth in their respective laps around the sun in 1984 and 2002. But it was too dim to see from 5 million miles (8 million kilometers) away, he said.
He predicts the object will spend about four months circling Earth once it’s captured in mid-November, before shooting back out into its own orbit around the sun next March.
Chodas doubts the object will slam into Earth — “at least not this time around.”
China's Mars probe Tianwen-1 successfully conducted a deep-space maneuver on Friday night (Beijing time), according to the China National Space Administration.
The probe completed the maneuver at 11 p.m. after its main engine worked for over 480 seconds.
The maneuver took place 29.4 million km from Earth, aiming to help the probe achieve a sound rendezvous with Mars.
Going forward, the probe will travel along the Earth-Mars transfer orbit for about four months and complete two or three mid-course orbital corrections.
China launched the Mars probe on July 23. It was designed to complete orbiting, landing, and roving in one mission. The probe will reach the red planet around February 2021.
It has successfully captured a photo of Earth and the moon and completed mid-course orbital corrections twice, as well as self-checks on multiple payloads.
A study on chimpanzees, the closest species to humans genetically, found cardiovascular health similarities between chimpanzees and humans.
When chimpanzees have a plant-based diet and substantial opportunities to exercise, they fall into "healthy" human ranges.
Lab chimpanzees, whose diet and exercise were limited, showed conditions indicative of cardiovascular disease risk, more like sedentary people, reports Xinhua.
The findings have been published in a special issue of Philosophical Transactions B on "The evolution of the primate aging process".
Researchers from the University of Michigan (UM) and University of New Mexico partnered with wildlife veterinarians in Uganda and Congo to examine cardiovascular profiles in chimpanzees living in African sanctuaries, according to the findings posted on UM's website on Monday.
These chimpanzees occupy large rainforest enclosures, consume a diet of fruits and vegetables, and generally experience conditions more similar to a wild chimpanzee lifestyle.
They measured blood lipids, body weight and body fat in 75 sanctuary chimpanzees during annual veterinary health check-ups, and then compared them to published data from laboratory-living chimpanzees.
Free-ranging chimpanzees in sanctuaries exhibited lower body weight and lower levels of lipids, both risk factors for human cardiovascular disease. Some of these disparities increased with age, indicating that the free-ranging chimpanzees stayed healthy as they got older.
"Our findings support the hypothesis that lifestyle shapes health in chimpanzees, similar to effects in humans, and contribute to an emerging understanding of cardiovascular health in evolutionary context," said Alexandra Rosati, UM assistant professor of psychology and anthropology.
The work also showed that chimpanzees living a naturalistic life have much lower levels of blood lipids even as they age, providing a new reference for understanding human health.
"These results show how the high-quality, natural conditions that chimpanzees experience in African sanctuaries fosters their long-term health," Rosati said.
China on Monday sent a new ocean-monitoring satellite into orbit from the Jiuquan Satellite Launch Center in northwest China.
A Long March-4B rocket carrying the Haiyang-2C (HY-2C) satellite took off at 1:40 p.m. (Beijing Time), according to the launch center, reports Xinhua.
The country's third ocean dynamic environment satellite, the HY-2C, will form a network with the previous HY-2B and subsequent HY-2D to carry out high-precision maritime environment monitoring.
Monday's launch was the 347th by the Long March rocket series.