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Scientists confirm 50-year-old theory that aliens could exploit a black hole for energy

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June 23 (UPI) — Lab experiments have confirmed the 50-year-old theory that an alien civilization could exploit a black hole for energy.

More than a half-century ago, British physicist Roger Penrose surmised that energy could be harvested from a black hole by dropping an object into it’s ergosphere, the outer layer of the black hole’s event horizon.

The object would need to be quickly split in two, allowing half to fall into the black hole and the other half recovered. According to Penrose’s theory, the recoil action would provide the recovered half of the object a loss of negative energy. It would, in effect, gain energy.

Not just any aliens could carry out such a complex engineering feat, Penrose acknowledged. If aliens were to harvest energy from a black hole, they’d need to be highly advanced.

In 1971, two years after Penrose published his theory, another physicist, Yakov Zel’dovich, claimed the idea could be put to the test on Earth using twisted light waves bounced off the surface of a cylinder spun at just the right speed. Zel’dovich claimed a phenomenon known as the rotational doppler effect would cause the reflected light waves to bounce back with surplus energy.

Zel’dovich’s proposal has gone untested, in part due to the need for the cylinder to rotate at speeds in excess of a billion revolutions per second — a technological impossibility.

To finally put Penrose’s original theory to the test, researchers at the University of Glasgow, in Scotland, developed an alternative experiment using sound waves instead of light waves. By using waves with lower frequencies, the test wouldn’t require the cylinder to spin so fast.

Researchers at the University of Glasgow’s School of Physics and Astronomy set up a unique combination of speakers to create a twist in the sound waves. Scientists directed the twisting sound waves toward a foam disc. Behind the disk, the team positioned a microphone.

Instead of bouncing off the foam disk, the sound waves traveled through and were picked up by the microphone on the other side. Recordings of the altered sound waves revealed changes in frequency and amplitude consistent with the doppler effect predicted by Zel’dovich.

Researchers detailed the results of their experiment this week in the journal Nature Physics.

“The linear version of the doppler effect is familiar to most people as the phenomenon that occurs as the pitch of an ambulance siren appears to rise as it approaches the listener but drops as it heads away,” lead study author Marion Cromb, a doctoral student at Glasgow, said in a news release. “It appears to rise because the sound waves are reaching the listener more frequently as the ambulance nears, then less frequently as it passes.”

“The rotational doppler effect is similar, but the effect is confined to a circular space,” Cromb said. “The twisted sound waves change their pitch when measured from the point of view of the rotating surface. If the surface rotates fast enough then the sound frequency can do something very strange — it can go from a positive frequency to a negative one, and in doing so steal some energy from the rotation of the surface.”

When researchers accelerated the spin of the foam disk, the sound from the speakers quieted, becoming too low to hear. As the disk spun faster, the pitch got higher and higher until it returned to its original pitch — only louder, with an amplitude 30 percent greater than before.

“What we heard during our experiment was extraordinary. What’s happening is that the frequency of the sound waves is being doppler-shifted to zero as the spin speed increases. When the sound starts back up again, it’s because the waves have been shifted from a positive frequency to a negative frequency,” Cromb said. “Those negative-frequency waves are capable of taking some of the energy from the spinning foam disc, becoming louder in the process — just as Zel’dovich proposed in 1971.”

Researchers suggest their surprise discovery has paved the way for a variety of new physics experiments. Scientists hope their test can be replicated using electromagnetic waves or some other kind of waves.



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Ryugu’s rubble suggests its short life has been rather turbulent

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Sept. 21 (UPI) — The asteroid Ryugu is a loose assemblage of fragments from a collision between two asteroids, according to new research published Monday in the journal Nature Astronomy.

Some asteroids are composed of large, solid pieces of rock, but Ryugu is more like a rubble pile than a rock. It is too small and fragile to have remained intact for very long — scientists estimate Ryugu formed between 10 million to 20 million years ago.

“Ryugu is too small to have survived the whole 4.6 billion years of solar system history,” Seiji Sugita, professor of planetary sciences at the University of Tokyo in Japan, said in a news release. “Ryugu-sized objects would be disrupted by other asteroids within several hundred million years on average.”

“We think Ryugu spent most of its life as part of a larger, more solid parent body,” Sugita said. “This is based on observations by Hayabusa-2 which show Ryugu is very loose and porous. Such bodies are likely formed from reaccumulations of collision debris.”

For the latest study, scientists used images collected by Hayabusa-2 to identify the different types of rock on Ryugu. Researchers were able to uncover clues to the asteroid’s violent past by analyzing the ratios of different rock types.

“Ryugu is considered a C-type, or carbonaceous, asteroid, meaning it’s primarily composed of rock that contains a lot of carbon and water,” said postdoctoral researcher Eri Tatsumi. “As expected, most of the surface boulders are also C-type; however, there are a large number of S-type, or siliceous, rocks as well. These are silicate-rich, lack water-rich minerals and are more often found in the inner, rather than outer, solar system.”

The presence of siliceous rocks suggests Ryugu was formed from the rubble created by a collision between between a small S-type asteroid and a larger C-type asteroid.

“We used the optical navigation camera on Hayabusa2 to observe Ryugu’s surface in different wavelengths of light, and this is how we discovered the variation in rock types. Among the bright boulders, C and S types have different albedos, or reflective properties,” said Tatsumi.

Once Hayabusa-2 returns rock samples to Earth, scientists plan to compare the asteroids geochemical composition to meteorites samples found on Earth.

“This could in turn tell us something new about the history of Earth and the solar system as a whole,” Tatsumi said.



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Study highlights carbon sequestration services provided by U.S. forests

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Sept. 21 (UPI) — Forests in the United States currently sequester approximately three decades worth of carbon dioxide emitted by the American fossil fuel industry, according to a new a study.

What’s more, forests and harvested wood products uptake approximately 14 percent of economy-wide CO2 emissions in the United States annually.

Despite declining carbon emissions in the United States, the contribution of forests to emissions offsets has remained stable. This, researchers say, suggests the ability of U.S. forests to absorb new carbon — an ability driven largely by forest regrowth — is slowly declining.

To better understand the ability of afforestation and reforestation activities to improve carbon sequestration capabilities, researchers analyzed data from more than 130,000 national forest inventory plots.

The findings — published Monday in the journal Proceedings of the National Academy of Sciences — confirmed that there is potential for U.S. forests to capture and store more carbon.

Researchers used forest inventory plots to estimate the total carbon storage capabilities provided by forests in the United States. Their analysis showed each acre of forest in the United States stores nearly 700 metric tons of CO2. But the data also showed forests are underperforming.

“There are opportunities on existing forestland to increase the contribution of forests to climate change mitigation,” researchers wrote in their paper.

Researchers found nearly 82 million acres of productive forestland in the U.S. are understocked with trees, characterized by tree coverage of less than 35 percent.

“Currently, there is federal infrastructure to produce and plant approximately 65 million seedlings per year, and state and private capacity is approximately 1.1 billion tree seedlings per year,” researchers wrote.

These efforts sequester between 16 and 28 million metric tons of CO2 annually.

According to the study’s authors, concentrating tree-planting efforts on understocked forest acreage could significantly increase carbon sequestration capacity in the United States.



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Bobcat fire threatens historic Mount Wilson Observatory

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Sept. 21 (UPI) — Days after officials declared the historic Mount Wilson Observatory in Los Angeles County safe from an aggressive fast-moving blaze, firefighters on Monday were attempting to beat back the Bobcat fire as it attempted to work its way up the mountain.

The Angeles National Forest said Sunday that the fire, which has grown to be one of the largest in the county’s history, was “threatening all of the values” on Mount Wilson. Officials had said Friday said it was safe after crews deployed strategic firing to protect the iconic observatory in the San Gabriel Mountains.

Strong winds and low humidity overnight helped the blaze to grow a few thousand acres to 105,345 acres as of 8 a.m. Monday, the Angeles National Forest said in a statement. It was 15% contained.

Engines, hand crews and aircraft on Monday were deployed to the north side of Mount Wilson to extinguish spot fires, the service said.

“Bobcat fire is making a hard push at Mount Wilson,” the Angeles National Forest said on Twitter. “Defensive strategic operations are beginning from Mount Wilson to the west.”

Thomas Meneghi, the observatory’s executive director, told the Los Angeles Times, that on Sunday eight additional strike units were seen being dispatched to the area after it was deemed safe two days prior.

“Just when I thought the danger was over — it wasn’t,” he said.

The observatory said on its Facebook Page Monday evening that the fire has picked up and is making its way toward the Mount Wilson drainage on the northwestern slope.

The Times reported that it’s the second time the observatory, historic for its role in space exploration, has been under threat of fire with crews protecting it from the Station fire of 2009, which holds the title for the county’s largest blaze at some 160,000 acres.

Due to the Bobcat fire encroaching on communities, the Los Angeles County Sheriff’s Office issued evacuations orders Monday for those who live in south and west of Upper Big Tujunga and east and north of Angeles Forest Highway, while the Los Angeles County Office of Emergency Management ordered residents of Camp Colby to leave the area immediately.

“This warning has been upgraded to an evacuation ordered,” the service announced via Twitter. “If you are in the identified area GO NOW! EVACUATE.”

Los Angeles County Fire Chief Daryl Osby told reporters and residents during a virtual press conference Monday evening that firefighters “scratch and claw” to protect every property they can.

Osby said this year has been a record fire season for California, with thousands of firefighters battling some 27 blazes, but added “the scary thing about all this” is that the fire season for Southern California wasn’t near finished.

Cal Fire said more than 3.6 million acres have been burned in nearly 8,000 fires, resulting in 7,097 structures impacted and at least 26 deaths.

Gov. Gavin Newsom called the wildfire season “historic” in a press conference on Monday, stating that last year, there were only 5,316 fires burning some 157,000 acres.

The Democratic governor said evictions have forced 23,154 people from their homes, adding that more than 6,400 structures have been wholly destroyed.

Six major fires continue to burn in the state, he said, including the August fire, the largest in the state’s history at 846,000 acres, which was at 34% contained.

In Plumas and Lassen counties, the North Complex fire, the fifth-largest ever in the state at 294,000 acres was at 64% contained, compared to 36% on Wednesday.

The Creek fire, in Fresno and Madera counties, was the seventh-largest fire in state history, and was at 278,000 acres and contained at 27%.

Concerning the Bobcat fire, he said they were deploying as many resources as possible to battle the blaze.

“We’re putting all the resources we possibly can on all these complexes but focusing, as we should, on that Bobcat fire,” he said.

Nationally, 78 large fires have consumed some 3.9 million acres this season, according to the national interagency Fire Center.

In Oregon, the Department of Forestry said some 7,500 personnel have been assigned to 10 major fires in the state.

The state’s Office of Emergency Management has confirmed nine people have died in the fires and five people were missing as of Monday.

Some 1 million acres have been burned statewide, destroying 2,268 residences and an additional 1,556 instructions, it said in a statement.

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