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Astronomers discover likely source of strange radio bursts from space – CBC.ca

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For more than 13 years, astronomers have been trying to determine the source of extremely powerful radio bursts that can travel billions of kilometres through space but only last a fraction of a second.

These signals — called fast radio bursts (FRBs) — were discovered in 2007 by two astrophysicists while poring through data collected in 2001 from the Parkes Observatory in New South Wales, Australia. Since then, dozens more have been detected, even a different form called repeating fast radio bursts. 

But just what is responsible for pumping out these extremely bright radio signals has remained shrouded in mystery, with even the odd whisper of whether or not it was astrophysical in the first place.

Until now.

Three independent teams of international astronomers, who published three separate papers published in the journal Nature Wednesday, have found one likely culprit: magnetars. 

Magnetars are a fascinating type of neutron star, the collapsed core of a massive star that exploded. They are spheres that are roughly the size of a city like Toronto or Montreal, but so dense that a piece of material the size of a sugar cube would weigh as much as a mountain, or one trillion kilograms. 

But a magnetar takes a neutron star to the extreme. While the magnetic field of a neutron star is trillions of times stronger than Earth’s, a magnetar’s is 1,000 times more than that. 

Over the past decade or so, there had been several theories as to what could produce FRBs, one of which was a magnetar. But the sources of the brief but powerful signals were too far away to confirm.

But on April 28, astronomers using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope in Penticton, B.C., and the Survey for Transient Astronomical Radio Emission 2 (STARE2) telescope captured an FRB burst from the same region of the sky. The pair of telescopes were able to confirm that it has been emitted from SGR 1935+2154, a known magnetar.

WATCH | New CHIME telescope unveiled in B.C.

Scientists hope CHIME, Canada’s largest radio telescope, will be a major step forward in uncovering the secrets of the universe 2:04

“When I looked at the data for the first time, I froze and was basically paralyzed with excitement,” said Christopher Bochenek, an astrophysicist at the California Institute of Technology in Pasadena, Calif., who is the lead author of a second paper. “Then it took me a few minutes to collect myself and make the call to a friend to be able to actually sit down and make sure this thing was actually real. 

“In about one millisecond, this magnetometer emitted as much energy in radio waves as the sun does in 30 seconds.”

‘In our backyard’

FRBs have been detected billions of light-years away, such as one called FRB 121102, discovered to repeat by Canadian astrophysicist Paul Scholz. 

But what makes this new FRB — designated FRB 200428 — particularly interesting is that it lies a mere 30,000 light-years away. 

“FRBs … are generally millions to billions of light-years away from us. But this thing is in our galaxy and much closer to us,” Scholz said. “Compared to [other] FRBs, it’s in our backyard, so we can study it in much more detail.”

The Five-hundred-meter Spherical Aperture Telescope (FAST) in Guizhou province, China, was used to monitor the magnetar SGR 1935+2154, which astronomers believe is associated with a fast radio burst, or FRB. (Bojun Wang, Jinchen Jiang/Qisheng Cui)

While the discovery is exciting, it still doesn’t put the mystery completely to rest.

“This event detected is a strong hint that magnetars that we have in our galaxy, the physical mechanism that’s going on there, is what could be causing FRBs — at least a portion of the FRB population,” Scholz said. “It certainly doesn’t solve the FRB problem completely, but it gives us a very strong indication that magnetars are capable of producing the types of emission that we see from FRBs.”

And what’s more, though astronomers now seem to have at least one potential source, it doesn’t explain the mechanism behind what is creating these powerful but brief bursts. 

“Emission mechanisms in physics and astronomy are hard to nail down in the details,” Scholz said. “There is a neutron star that has an extremely high magnetic field, and … it tells you that the magnetar, the neutron star, and it’s magnetosphere are powering that event. How exactly the energy from the magnetic field gets released as radio emission? I think theorists will debate that for decades.”

Subsequent follow-up by the Five-hundred meter Aperture Spherical Telescope (FAST) in Guizhou, China, supported the observations, although the lead author of that paper said he had his doubts. 

“With CHIME and STARE2, I was actually not very optimistic. I thought, because FRBs from small distances are not very bright and repeating, so probably you don’t have a smoking gun,” said Bing Zhang, an astrophysicist at the University of Nevada, Las Vegas.

That’s because there were so many — nearly 50 — models of what could be producing these bursts. 

“However, this discovery in our backyard … tells us that they are actually coming from magnetars. And now, we can say that at least one model can [create] at least some, and probably all FRBs in the universe,” said Zhang.

Astronomers now hope that more FRBs can be traced back to other magnetars in our solar system, of which roughly 30 are known.

“All this technology that we have comes out of our understanding of the universe, of physics. And the only way we achieve that understanding is by studying nature: magnetars and fast radio bursts and extreme phenomenon in nature,” Scholz said. “And through understanding them, we will have a better understanding of how the universe works, how physics works.”

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Japan awaits spacecraft return with asteroid soil samples – Vancouver Is Awesome

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TOKYO — Japan’s space agency said the Hayabusa2 spacecraft successfully separated a capsule and sent it toward Earth to deliver samples from a distant asteroid that could provide clues to the origin of the solar system and life on our planet.

The Japan Aerospace Exploration Agency said the capsule successfully detached Saturday afternoon from 220,000 kilometres (136,700 miles) away in a challenging operation that required precision control. The capsule is now descending to land in a remote, sparsely populated area of Woomera, Australia, on Sunday.

Hayabusa2 left the asteroid Ryugu, about 300 million kilometres (180 million miles) away, a year ago. After the capsule release, it is now moving away from Earth to capture images of the capsule descending to the planet.

Yuichi Tsuda, project manager at the space agency JAXA, stood up and raised his fists as everyone applauded the moment command centre officials confirmed the successful separation of the capsule.

Hayabusa2’s return with the world’s first asteroid subsurface samples comes weeks after NASA’s OSIRIS-REx spacecraft made a successful touch-and-go grab of surface samples from asteroid Bennu. China, meanwhile, announced this week its lunar lander collected underground samples and sealed them within the spacecraft for return to Earth, as space developing nations compete in their missions.

Many Hayabusa2 fans gathered to observe the moment of the capsule separation at public viewing events across the country, including one at the Tokyo Dome stadium.

In the early hours of Sunday, the capsule, protected by a heat shield, will briefly turn into a fireball as it reenters the atmosphere 120 kilometres (75 miles) above Earth. At about 10 kilometres (6 miles) above ground, a parachute will open to slow its fall and beacon signals will be transmitted to indicate its location.

JAXA staff have set up satellite dishes at several locations in the target area to receive the signals, while also preparing a marine radar, drones and helicopters to assist in the search and retrieval of the pan-shaped capsule, 40 centimetres (15 inches) in diameter.

Australian National University space rock expert Trevor Ireland, who is in Woomera for the arrival of the capsule, said he expected the Ryugu samples to be similar to the meteorite that fell in Australia near Murchison in Victoria state more than 50 years ago.

“The Murchison meteorite opened a window on the origin of organics on Earth because these rocks were found to contain simple amino acids as well as abundant water,” Ireland said, “We will examine whether Ryugu is a potential source of organic matter and water on Earth when the solar system was forming, and whether these still remain intact on the asteroid.”

Scientists say they believe the samples, especially ones taken from under the asteroid’s surface, contain valuable data unaffected by space radiation and other environmental factors. They are particularly interested in analyzing organic materials in the samples.

JAXA hopes to find clues to how the materials are distributed in the solar system and are related to life on Earth.

For Hayabusa2, it’s not the end of the mission it started in 2014. After dropping the capsule, it will return to space and head to another distant small asteroid called 1998KY26 on a journey slated to take 10 years one way, for a possible research including finding ways to prevent meteorites from hitting Earth.

So far, its mission has been fully successful. It touched down twice on Ryugu despite its extremely rocky surface, and successfully collected data and samples during the 1 1/2 years it spent near Ryugu after arriving there in June 2018.

In its first touchdown in February 2019, it collected surface dust samples. In a more challenging mission in July that year, it collected underground samples from the asteroid for the first time in space history after landing in a crater that it created earlier by blasting the asteroid’s surface.

Asteroids, which orbit the sun but are much smaller than planets, are among the oldest objects in the solar system and therefore may help explain how Earth evolved.

Ryugu in Japanese means “Dragon Palace,” the name of a sea-bottom castle in a Japanese folk tale.

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Associated Press writer Dennis Passa in Brisbane, Australia, contributed to this report.

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Follow Mari Yamaguchi on Twitter at https://www.twitter.com/mariyamaguchi

Mari Yamaguchi, The Associated Press








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Japan's Hayabusa2 Asteroid Journey Ends With a Hunt in Australia's Outback – The New York Times

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Japan’s Journey to an Asteroid Ends With a Hunt in Australia’s Outback

The Hayabusa2 mission cements Japan’s role in exploring the solar system, but finding its asteroid cargo presents one last challenge.

Members of JAXA, Japan’s space agency, installed an antenna in Woomera, southern Australia, in preparation for the Hayabusa2’s return to Earth.
Credit…JAXA, via Associated Press

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  • Dec. 5, 2020, 12:01 a.m. ET

Japan’s space agency is nearing the end of a journey of discovery that aims to shed light on the earliest eons of the solar system and possibly provide clues about the origins of life on Earth.

But first, it is going to have to go on a scavenger hunt in the Australian outback.

This weekend, bits of an asteroid will land in a barren region near Woomera, South Australia. These are being ferried to Earth by Hayabusa2, a robotic space probe launched by JAXA, Japan’s space agency, in 2014 to explore an asteroid named Ryugu, a dark, carbon-rich rock a bit more than half a mile wide.

The success of the mission and the science it produces will raise Japan’s status as a central player in deep space exploration, together with NASA, the European Space Agency and Russia. JAXA currently has a spacecraft in orbit around Venus studying that planet’s hellish climate and is collaborating with the Europeans on a mission that is on its way to Mercury.

In the coming years, Japan plans to bring back rocks from Phobos, a moon of Mars, and contribute to NASA’s Artemis program to send astronauts to Earth’s moon.

But the immediate challenge will be searching in darkness for a 16-inch-wide capsule containing the asteroid samples somewhere amid hundreds of square miles in a region 280 miles north of Adelaide, the nearest large city.

“It’s really in the middle of nowhere,” said Shogo Tachibana, the principal investigator in charge of the analysis of the Hayabusa2 samples. He is part of a team of more than 70 people from Japan who have arrived in Woomera for recovery of the capsule. The area, used by the Australian military for testing, provides a wide open space that is ideal for the return of an interplanetary probe.

The small return capsule separated from the main spacecraft about 12 hours before the scheduled landing, when it was about 125,000 miles from Earth. JAXA will broadcast live coverage of the capsule’s landing beginning at 11:30 a.m. Eastern time on Saturday. (It will be pre-dawn hours on Sunday in Australia.)

The capsule is expected to hit the ground a few minutes before noon.

Credit…JAXA/JiJi Press, via Agence France-Presse — Getty Images
Credit…JAXA, via Associated Press
Credit…Agence France-Presse — Getty Images
Credit…JAXA/EPA, via Shutterstock

In an interview, Makoto Yoshikawa, the mission manager, said there is an uncertainty of about 10 kilometers, or about six miles, in pinpointing where the capsule will re-enter the atmosphere. At an altitude of six miles, the capsule will release a parachute, and where it will drift as it descends will add to the uncertainty.

“The landing place depends on the wind on that day,” Dr. Yoshikawa said. The area that searchers might have to cover could stretch some 60 miles, he said.

The trail of the fireball of superheated air created by the re-entering capsule will help guide the recovery team, as will the capsule’s radio beacon. The task will become much more difficult if the beacon fails or if the parachute fails to deploy.

There is a bit of a rush, too. The team hopes to recover the capsule, perform initial analysis and whisk it back to Japan within 100 hours. Even though the capsule is sealed, the worry is that Earth air will slowly leak in. “There is no perfect sealing,” Dr. Tachibana said.

Once the capsule is found, a helicopter will take it to a laboratory that has been set up at the Australian air force base at Woomera. There an instrument will extract any gases within the capsule that may have been released by the asteroid rocks as they were shaken and broken during re-entry. Dr. Yoshikawa said the scientists would also like to see if they can detect any solar wind particles of helium that slammed into the asteroid and became embedded in the rocks.

The gases would also reassure the scientists that Hayabusa2 did indeed successfully collect samples from Ryugu. A minimum of 0.1 grams, or less than 1/280th of an ounce, is needed to declare success. The hope is the spacecraft brought back several grams.

In Japan, the Hayabusa2 team will begin analysis of the Ryugu samples. In about a year, some of the samples will be shared with other scientists for additional study.

To gather these samples, Hayabusa2 arrived at the asteroid in June 2018. It executed a series of investigations, each of escalating technical complexity. It dropped probes to the surface of Ryugu, blasted a hole in the asteroid to peer at what lies beneath and twice descended to the surface to grab small pieces of the asteroid, an operation that proved much more challenging than expected because of the many boulders on the surface.

Displays in the Royal Australian Air Force’s Woomera range complex, where Hayabusa2’s landing will be monitored.
Credit…Morgan Sette/Agence France-Presse — Getty Images

Small worlds like Ryugu used to be of little interest to planetary scientists who focused on studying planets, said Masaki Fujimoto, deputy director general of the Institute of Space and Astronautical Science, part of JAXA. “Minor bodies, who cares?” he said. “But if you are serious about the formation of planetary systems, small bodies actually matter.”

Studying water trapped in minerals from Ryugu could give hints if the water in Earth’s oceans came from asteroids, and if carbon-based molecules could have seeded the building blocks for life.

Part of the Ryugu samples will go to NASA, which is bringing back some rocks and soil from another asteroid with its OSIRIS-REX mission. The OSIRIS-REX space probe has been studying a smaller carbon-rich asteroid named Bennu and it will start back to Earth next spring, dropping off its rock samples in September 2023.

Ryugu and Bennu turned out to be surprisingly similar in some ways, both looking like spinning tops and with surfaces covered with boulders, but different in other ways. The rocks on Ryugu appear to contain much less water, for one. The significance of the similarities and differences will not become clear until after scientists study the rocks in more detail.

“When the OSIRIS-REX sample comes back, we will have lessons learned from the Hayabusa2 mission,” said Harold C. Connolly Jr., a geology professor at Rowan University in New Jersey and the mission sample scientist for OSIRIS-REX. “The similarities and differences are absolutely fascinating.”

Credit…NASA/Goddard/University of Arizona
Credit…NASA/Goddard/University of Arizona, via Associated Press

Dr. Connolly hopes to go to Japan next summer to take part in analyzing the Ryugu samples.

Hayabusa2 is not Japan’s first planetary mission. Indeed, its name points to the existence of Hayabusa, an earlier mission that brought back samples from another asteroid, Itokawa. But that mission, which launched in 2003 and returned in 2010, faced major technical problems. So did JAXA’s Akatsuki spacecraft, currently in orbit around Venus, which the Japanese agency managed to restore to a scientific mission after years of difficulty. A Japanese mission to Mars also failed in 2003.

By contrast, operations of Hayabusa2 have gone almost flawlessly, even though it retains the same general design as its predecessor. “Actually, there are no big issues,” Dr. Yoshikawa, the mission manager, said. “Of course, small ones.”

He said the team studied in detail the failures on Hayabusa and made changes as needed, and also conducted numerous rehearsals to try to anticipate any contingencies it might encounter.

The Japanese missions generally operate on smaller budgets than NASA’s and thus often carry fewer instruments. Hayabusa2’s cost is less than $300 million while OSIRIS-REX’s price will run about $1 billion.

Dropping off the Ryugu samples is not the end of the Hayabusa2 mission. After releasing the return capsule, the main spacecraft shifted course to avoid a collision with Earth, missing by 125 miles. It will now travel to another asteroid, a tiny one designated 1998 KY26 that is only 100 feet in diameter but spinning rapidly, completing one rotation in less than 11 minutes.

Hayabusa2 will use two flybys of Earth to fling itself toward KY26, finally arriving in 2031. It will conduct some astronomical experiments during its extended deep space journey, and the spacecraft still carries one last projectile that it may use to test that space rock’s surface.

Credit…Agence France-Presse — Getty Images

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Watch unreal drone footage of Arecibo Observatory's catastrophic collapse – CNET

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The National Science Foundation released stunning video footage Thursday capturing the exact dramatic moment the Arecibo Observatory’s 900-ton platform fell into the 1,000-foot wide dish below. A drone happened to be performing an up-close investigation of the cables that still held the platform above the dish as the cables snapped on Tuesday.

The video of the massive radio telescope shows both the drone footage and the view from a camera in the visitor center that shows the platform falling into the dish just above the jungle floor in Arecibo, Puerto Rico. Two massive chunks of the cement towers that the cables were attached to can also be seen falling.

Two of the cables had previously broken, one in August and another in November, destabilizing the telescope.

A drone was inspecting the site atop one of the towers, where one of the previous cable breaks had occurred, when the rest suddenly snapped. 

The NSF had recently decided to decommission the telescope after a second cable broke in November.

“It was a dangerous situation,” John Abruzzo, who is with an engineering consulting firm called Thornton Tomasetti that was contracted by the NSF, told reporters Thursday. “Those cables could have failed at any time.” 

On Tuesday, they did.

The NSF reports that no one was injured in the collapse and that the visitor center sustained only minor damage.

The telescope, which functioned for nearly 60 years, was the backdrop to a dramatic fight scene in the 1995 James Bond movie GoldenEye with Pierce Brosnan. It also appeared in the 1997 Jodie Foster movie Contact. But Arecibo’s true legacy lies in the many scientific discoveries it made possible. It explored pulsars, expanded our knowledge of Mercury, spotted exoplanets and found fast radio bursts.  

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