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"Asteroid" entering Earth's orbit may actually be a 1966 NASA rocket – Barrie 360 – Barrie 360

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Sophie Lewis – CBS News

The jig may be up for an “asteroid” that’s expected to get nabbed by Earth’s gravity and become a mini-moon next month. 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.

Chodas told CBS News that it is very rare for an object orbiting the sun to get captured into the Earth’s orbit.

“The object has to have a very special orbit around the sun for such a capture to occur,” he said. “It has happened a couple times before for natural objects, that we know of, and only once before for an old rocket stage.”

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 based on its brightness. That’s in the ballpark of the old Centaur, which would be less than 32 feet long including its engine nozzle and 10 feet 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, 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 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.”

banner image of an Atlas Centaur 7 rocket on the launchpad at Cape Canaveral, Florida via San Diego Air and Space Museum

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Scientists Peer Inside an Asteroid – Is Bennu in the Process of Spinning Itself Into Pieces? – SciTechDaily

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OSIRIS REx Arrives at Asteroid Bennu

This series of images taken by the OSIRIS-REx spacecraft shows Bennu in one full rotation from a distance of around 50 miles (80 km). The spacecraft’s PolyCam camera obtained the thirty-six 2.2-millisecond frames over a period of four hours and 18 minutes. Credit: NASA’s Goddard Space Flight Center/University of Arizona

New findings from NASA’s OSIRIS-REx mission suggest that the interior of the asteroid Bennu could be weaker and less dense than its outer layers—like a crème-filled chocolate egg flying though space.

The results appear in a study published in the journal Science Advances and led by the University of Colorado Boulder’s OSIRIS-REx team, including professors Daniel Scheeres and Jay McMahon. The findings could give scientists new insights into the evolution of the solar system’s asteroids—how bodies like Bennu transform over millions of years or more.  

OSIRIS-REx rendezvoused with Bennu, an asteroid orbiting the sun more than 200 million miles from Earth, in late 2018. Since then, the spacecraft, built by Colorado-based Lockheed Martin, has studied the object in more detail than any other asteroid in the history of space exploration.

So far, however, one question has remained elusive: What’s Bennu like on the inside?

Bennu Orbit Diagram

Diagram of the orbit of Bennu in relation to Earth and other planets. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

Scheeres, McMahon and their colleagues on the mission’s radio science team now think that they have an answer—or at least part of one. Using OSIRIS-REx’s own navigational instruments and other tools, the group spent nearly two years mapping out the ebbs and flows of Bennu’s gravity field. Think of it like taking an X-ray of a chunk of space debris with an average width about the height of the Empire State Building.

“If you can measure the gravity field with enough precision, that places hard constraints on where the mass is located, even if you can’t see it directly,” said Andrew French, a coauthor of the new study and a former graduate student at CU Boulder, now at NASA’s Jet Propulsion Laboratory (JPL).

What the team has found may also spell trouble for Bennu. The asteroid’s core appears to be weaker than its exterior, a fact that could put its survival at risk in the not-too-distant future.

“You could imagine maybe in a million years or less the whole thing flying apart,” said Scheeres, a distinguished professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences.

Evolution of asteroids

Of course, that’s part of the fun of studying asteroids. Scheeres explained that Bennu belongs to a class of smaller bodies that scientists call “rubble pile” asteroids—which, as their name suggests, resemble loosely held-together mounds of debris. 

Asteroids also change over time more than people think. 

“None of them have sat out there unchanging since the dawn of the solar system,” Scheeres said. “They’re being changed by things like sunlight affecting how they spin and collisions with other asteroids.”

To study how Bennu and other similar asteroids may change, however, he and his colleagues needed to take a peek inside.

Asteroid Bennu Particles

OSIRIS-REx observed small bits of material leaping off the surface of the asteroid Bennu on January 19, 2019. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

This is where the team got lucky. When OSIRIS-REx first arrived at Bennu, the spacecraft spotted something unusual: Over and over again, tiny bits of material, some just the size of marbles, seemed to pop off the asteroid and into space. In many cases, those particles circled Bennu before falling back down to the surface. Members of the mission’s radio science team at JPL were able to witness how the body’s gravity worked first-hand—a bit like the apocryphal story of Isaac Newton inferring the existence of gravity after observing an apple falling on his head. 

“It was a little like someone was on the surface of the asteroid and throwing these marbles up so they could be tracked,” Scheeres said. “Our colleagues could infer the gravity field in the trajectories those particles took.”

Squishy center

In the new study, Scheeres and his colleagues combined those records of Bennu’s gravity at work with data from OSIRIS-REx itself—precise measurements of how the asteroid tugged on the spacecraft over a period of months. They discovered something surprising: Before the mission began, many scientists had assumed that Bennu would have a homogenous interior. As Scheeres put it, “a pile of rocks is a pile of rocks.” 

But the gravity field measurements suggested something different. To explain those patterns, certain chunks of Bennu’s interior would likely need to be more tightly packed together than others. And some of the least dense spots in the asteroid seemed to lie around the distinct bulge at its equator and at its very core.

“It’s as if there is a void at its center, within which you could fit a couple of football fields,” Scheeres said.

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Now, thanks to laser altimetry data and high-resolution imagery from OSIRIS-REx, we can take a tour of Bennu’s remarkable terrain. Credit: NASA’s Goddard Space Flight Center

The asteroid’s spin may be responsible for that void. Scientists know that the asteroid is spinning faster and faster over time. That building momentum could, Scheeres said, be slowly pushing material away from the asteroid’s center and toward its surface.  Bennu, in other words, may be in the process of spinning itself into pieces.

“If its core has a low density, it’s going to be easier to pull the entire asteroid apart,” Scheeres said.

For the scientist, the new findings are bittersweet: After measuring Bennu’s gravity field, Scheeres and his team have mostly wrapped up their work on the OSIRIS-REx mission. 

Their results have contributed to the mission’s sample analysis plan—currently in development. The returned sample will be analyzed to determine the cohesion between grains—a key physical property that affects the mass distribution observed in their study.

“We were hoping to find out what happened to this asteroid over time, which can give us better insight into how all of these small asteroids are changing over millions, hundreds of millions or even billions of years,” Scheeres said. “Our findings exceeded our expectations.”

Read Asteroid Bennu Secrets Unlocked by NASA’s OSIRIS-REx Ahead of Historic Heist for more on this and related research.

“Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu” by D. J. Scheeres, A. S. French, P. Tricarico, S. R. Chesley, Y. Takahashi, D. Farnocchia, J. W. McMahon, D. N. Brack, A. B. Davis, R.-L. Ballouz, E. R. Jawin, B. Rozitis, J. P. Emery, A. J. Ryan, R. S. Park, B. P. Rush, N. Mastrodemos, B. M. Kennedy, J. Bellerose, D. P. Lubey, D. Velez, A. T. Vaughan, J. M. Leonard, J. Geeraert, B. Page, P. Antreasian, E. Mazarico, K. Getzandanner, D. Rowlands, M. C. Moreau, J. Small, D. E. Highsmith, S. Goossens, E. E. Palmer, J. R. Weirich, R. W. Gaskell, O. S. Barnouin, M. G. Daly, J. A. Seabrook, M. M. Al Asad, L. C. Philpott, C. L. Johnson, C. M. Hartzell, V. E. Hamilton, P. Michel, K. J. Walsh, M. C. Nolan and D. S. Lauretta, 8 October 2020, Science Advances.
DOI: 10.1126/sciadv.abc3350

The University of Arizona leads science operations for OSIRIS-REx. NASA’s Goddard Space Flight Center in Maryland manages the overall mission.

Other coauthors on the new study include researchers at the Jet Propulsion Laboratory, Smithsonian Institution, The Open University, Northern Arizona University, KinetX Aerospace, Inc., NASA Goddard Space Flight Center, University of Maryland, Johns Hopkins University, York University, University of British Columbia, Southwest Research Institute, Université Côte d’Azur and University of Arizona.

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Geologists might have found a long-lost tectonic plate – Tech Explorist

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Jonny Wu and Spencer Fuston
Jonny Wu (left), assistant professor of geology in the UH Department of Earth and Atmospheric Sciences, and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era.

The existence of a tectonic plate called Resurrection has long been controversial among geophysicists. Some believe that it never existed, while others say that it is subducted into the Earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.

A new study by the University of Houston College of Natural Sciences and Mathematics shed light on this- suggesting that the Resurrection plate existed. Scientists believe they have found the remains of the missing plate, Resurrection in northern Canada-crushed, reshaped, and buried through subduction processes.

For this study, scientists used a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era.

D block diagram across North America showing a mantle tomography image
A 3D block diagram across North America showing a mantle tomography image reveals the Slab Unfolding method used to flatten the Farallon tectonic plate. By doing this, Fuston and Wu were able to locate the lost Resurrection plate.

The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates, and geologists have always known there were two plates in the Pacific Ocean around then called Kula and Farallon. Be that as it may, there has been discussion about a potential third plate, Resurrection, which has shaped a unique volcanic belt along with Alaska and Washington State.

According to scientists, this study could help geologists predict volcanic hazards and mineral and hydrocarbon deposits.

 plate tectonic reconstruction
This image shows plate tectonic reconstruction of western North America 60 million years ago showing subduction of three key tectonic plates, Kula, Farallon and Resurrection.

Spencer Fuston, a third-year geology doctoral student, said, “We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data support.”

Using 3-D mapping technology, scientists applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.

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Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences, said, “When ‘raised’ back to the Earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record.”

Journal Reference:
  1. Spencer Fuston et al., Raising the Resurrection plate from an unfolded-slab plate tectonic reconstruction of northwestern North America since early Cenozoic time, GSA Bulletin (2020). DOI: 10.1130/B35677.1

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Researchers rediscover tectonic plate lost for 60 million years – lintelligencer

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Researchers rediscover tectonic plate lost for 60 million years

The existence of a tectonic plate called Resurrection has long been a topic of debate among geologists, with some arguing it was never real. Others say it subducted – moved sideways and downward – into the earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.

A team of geologists at the University of Houston College of Natural Sciences and Mathematics believes they have found the lost plate in northern Canada by using existing mantle tomography images – similar to a CT scan of the earth’s interior. The findings, published in Geological Society of America Bulletin, could help geologists better predict volcanic hazards as well as mineral and hydrocarbon deposits.

“Volcanoes form at plate boundaries, and the more plates you have, the more volcanoes you have,” said Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences. “Volcanoes also affect climate change. So, when you are trying to model the earth and understand how climate has changed since time, you really want to know how many volcanoes there have been on earth.”

Wu and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era. The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates and geologists have always known there were two plates in the Pacific Ocean at that time called Kula and Farallon. But there has been discussion about a potential third plate, Resurrection, having formed a special type of volcanic belt along Alaska and Washington State.

“We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data supports,” Fuston said.

Using 3D mapping technology, Fuston applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.

“When ‘raised’ back to the earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record,” explained Wu.

[embedded content]

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