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Tag Archives: Cooling
Stock Market Today: Nasdaq, S&P 500 Close Higher After CPI Report Shows Cooling Inflation – The Wall Street Journal
- Stock Market Today: Nasdaq, S&P 500 Close Higher After CPI Report Shows Cooling Inflation The Wall Street Journal
- S&P 500, Nasdaq close at highest levels since April 2022, buoyed by cooler-than-expected inflation report: Live updates CNBC
- Stocks pop as inflation continues cooldown: Stock market news today Yahoo Finance
- Market Volatility Declines Ahead Of CPI; S&P 500 Gains – Citigroup (NYSE:C), Amazon.com (NASDAQ:AMZN) Benzinga
- Cooling inflation in the US brings slight relief to tech valuations TechCrunch
- View Full Coverage on Google News
Hiring, Wage Gains Eased in December, Pointing to a Cooling Labor Market in 2023
The U.S. labor market is losing momentum as hiring and wage growth cooled in December, showing the effects of slower economic growth and the Federal Reserve’s interest-rate increases.
After two straight years of record-setting payroll growth following the pandemic-related disruptions, the labor market is starting to show signs of stress. That suggests 2023 could bring slower hiring or outright job declines as the overall economy slows or tips into recession.
Employers added 223,000 jobs in December, the smallest gain in two years, the Labor Department said Friday. Average hourly earnings were up 4.6% in December from the previous year, the narrowest increase since mid-2021, and down from a March peak of 5.6%.
All told, employers added 4.5 million jobs in 2022, the second-best year of job creation after 2021, when the labor market rebounded from Covid-19 shutdowns and added 6.7 million jobs. Last year’s gains were concentrated in the first seven months of the year. More recent data and a wave of tech and finance-industry layoffs suggest the labor market, while still vibrant, is cooling.
“I do expect the economy to slow noticeably by June, and in the second half of the year we’ll see a greater pace of slowing if not outright contraction,” said
Joe Brusuelas,
chief economist at RSM U.S.
Friday’s report sent markets rallying as investors anticipated it would cause the Fed to slow its pace of rate increases. The central bank’s next policy meeting starts Jan. 31. The Fed’s aggressive rate increases aimed at combating inflation didn’t significantly cool 2022 hiring, but revisions to wage growth showed recent gains weren’t as brisk as previously thought.
The Dow Jones Industrial Average rose 700.53 points, or 2.13%, on Friday. The S&P 500 Index was up 2.28% and NASDAQ Composite Index advanced 2.56%. The benchmark 10-year Treasury yield declined 0.15 percentage point to 3.57%. Yields fall as bond prices rise.
The unemployment rate fell to 3.5% in December from 3.6% in November, matching readings earlier in 2022 and just before the pandemic began as a half-century low. Fed officials said last month the jobless rate would rise in 2023. December job gains were led by leisure and hospitality, healthcare and construction.
Historically low unemployment and solid hiring, however, might mask some signs of weakness. The labor force participation rate, which measures the share of adults working or looking for work, rose slightly to 62.3% in December but is still well below prepandemic levels, one possible factor that could make it harder for employers to fill open positions.
The average workweek has declined over the past two years and in December stood at 34.3 hours, the lowest since early 2020.
Hiring in temporary help services has fallen by 111,000 over the past five months, with job losses accelerating. That could be a sign that employers, faced with slowing demand, are reducing their employees’ hours and pulling back from temporary labor to avoid laying off workers.
The tech-heavy information sector lost 5,000 jobs in December, the Labor Department report showed. Retail saw a 9,000 rise in payrolls, snapping three straight months of declines.
Tech companies cut more jobs in 2022 than they did at the height of the Covid-19 pandemic, according to layoffs.fyi, which tracks industry job cuts. On Wednesday,
Salesforce Inc.
said it would cut 10% of its workforce, unwinding a hiring spree during the pandemic. The Wall Street Journal reported that
Amazon.com Inc.
would lay off 18,000 people, roughly 1.2% of its total workforce. Other companies, such as
parent
Meta Platforms Inc.,
DoorDash Inc.
and
Snap Inc.,
have also recently cut positions.
Companies in the interest-rate-sensitive housing and finance sectors, including
Redfin Corp.
,
Morgan Stanley
and
Goldman Sachs Group Inc.,
have also moved to reduce staff.
Months where overall jobs gained
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By the end of 2022, the U.S. had added nearly 2 million jobs since the end of 2019
More than 20 million jobs were lost near the start of the pandemic
Employment returns to prepandemic level
A monthly gain of more than 4 million jobs
Months where
overall jobs gained
Months where
overall jobs declined
By the end of 2022, the U.S. had added nearly 2 million jobs since the end of 2019
More than 20 million jobs were lost near the start of the pandemic
Employment returns to prepandemic level
A monthly gain of more than 4 million jobs
Months where
overall jobs gained
Months where
overall jobs declined
By the end of 2022, the U.S. had added nearly 2 million jobs since the end of 2019
More than 20 million jobs were lost near the start of the pandemic
Employment returns to prepandemic level
A monthly gain of more than 4 million jobs
Months where
overall jobs gained
Months where
overall jobs declined
By the end of 2022, the U.S. had added nearly 2 million jobs since the end of 2019
More than 20 million jobs were lost near the start of the pandemic
Employment returns to prepandemic level
A monthly gain of more than 4 million jobs
Months where
overall jobs gained
Months where
overall jobs declined
By the end of 2022, the U.S. had added nearly 2 million jobs since the end of 2019
More than 20 million jobs were lost near the start of the pandemic
Employment returns to prepandemic level
A monthly gain of more than 4 million jobs
Other data released this week point to a slowing U.S. economy. New orders for manufactured goods fell a seasonally adjusted 1.8% in November, the Commerce Department said Friday. Business surveys showed a contraction in economic activity in December, according to the Institute for Supply Management. Manufacturing firms posted the second-straight contraction following 29 months of expansion, and services firms snapped 30 straight months of growth in December.
Economists surveyed by The Wall Street Journal last fall saw a 63% probability of a U.S. recession in 2023. They saw the unemployment rate rising to 4.7% by December 2023.
“We’ve obviously been in a situation over the past few months where employment growth has been holding up surprisingly well and is slowing very gradually,” said
Andrew Hunter,
senior U.S. economist at Capital Economics. “There are starting to be a few signs that we’re maybe starting to see a bit more of a sharp deterioration.”
Max Rottersman, a 61-year-old independent software developer, said he had been very busy with consulting jobs during much of the pandemic. But that changed over the summer when work suddenly dried up.
“I’m very curious to see whether I’m in high demand in the next few months or whether—what I sort of expect will happen—there will be tons of firing,” he said.
Despite some signs of cooling, the labor market remains exceptionally strong. On Wednesday, the Labor Department reported that there were 10.5 million job openings at the end of November, unchanged from October, well more than the number of unemployed Americans seeking work.
Some of those open jobs are at Caleb Rice’s home-renovation business in Calhoun, Tenn., which has been consistently busy since the start of the pandemic. The small company has raised pay and gone to a four-day week in an effort to hold on to workers.
“If I could get three more skilled hands right now, I’d be comfortable,” Mr. Rice said. “The way it goes is I’ll hire five, two will show up and of those two one won’t be worth a flip.”
Fed officials have been trying to engineer a gradual cooling of the labor market by raising interest rates. Officials are worried that a too-strong labor market could lead to more rapid wage increases, which in turn could put upward pressure on inflation as firms raise prices to offset higher labor costs.
The central bank raised rates at each of its past seven meetings and has signaled more rate increases this year to bring inflation down from near 40-year highs. Fed officials will likely take comfort in the slowdown in wage gains, which could prompt them to raise rates at a slower pace, Mr. Brusuelas, the economist, said.
“We’re closer to the peak in the Fed policy rate than we were prior to the report, and the Fed can strongly consider a further slowing in the pace of its hikes,” he said. “We could plausibly see a 25-basis-point hike versus a 50-basis-point hike at the Feb. 1 meeting.”
Write to David Harrison at david.harrison@wsj.com
Corrections & Amplifications
A graphic in an earlier version of this article showing the change in nonfarm payrolls since the end of 2019 was incorrectly labeled as change since January 2020. (Corrected on Jan. 6)
Copyright ©2022 Dow Jones & Company, Inc. All Rights Reserved. 87990cbe856818d5eddac44c7b1cdeb8
PCE, the Fed’s preferred inflation gauge, shows prices cooling
Minneapolis
CNN
—
The trend is clear: Inflation is cooling off in America.
The Federal Reserve’s preferred measurement of inflation showed price increases continued to moderate in November, providing yet another welcome indication that the period of painfully high prices has peaked.
The Personal Consumption Expenditures price index, or PCE, rose 5.5% in November from a year earlier, the Commerce Department reported Friday. That’s lower than in October, when prices rose 6.1% annually.
In November alone, prices rose just 0.1% from October.
Core PCE, which excludes the volatile food and energy categories, was up 4.7% annually and 0.2% on a monthly basis, matching expectations of economists polled by Refinitiv.
The annual increases for both PCE inflation indexes hit their lowest levels since October 2021 and follows continued declines in other inflation gauges, such as the Consumer Price Index and Producer Price Index.
PCE, specifically the core measurement, is the Fed’s favored inflation gauge, since it provides a more complete picture of costs for consumers.
Friday’s report also showed that spending continued to rise in November, but at a much slower pace than in previous months. Spending was up 0.1% in November as compared to 0.8% the month before. Personal income increased by 0.4% in November, down from 0.7% in October.
The November PCE report, the last major inflation gauge released in 2022, provided a snapshot of an economy in transition. Tasked with reining in the highest inflation since the early 1980s, the Fed has undertaken a series of blockbuster interest rate hikes to squelch demand.
In its seven meetings starting in March, the central bank’s policymaking arm raised its benchmark interest rate by a cumulative 4.25 percentage points. The sharp hike in rates has started to filter through the economy, its effects showing up first in areas such as real estate, where mortgage rates were 6.27% this week, more than double the rate seen last year at this time, according to Freddie Mac data.
“The economy is moving in the right direction from the Federal Reserve’s perspective at the end of 2022, but not quickly enough,” Gus Faucher, chief economist for PNC Financial Services, said in a statement. “Higher interest rates are weighing on consumer spending, particularly for durable goods, and inflation is slowing.”
Inflation has moderated in recent months, especially on items like goods as supply chain bottlenecks have eased and consumers focused more spending in areas like leisure and hospitality.
However, inflation within the services sector has been a little “sticky,” and not abating as quickly. Friday’s PCE report showed the services index posted a monthly increase of 0.4% – unchanged from October’s rate – and a year-over-year increase of more than 11%, Faucher noted.
While much of the services inflation is due to housing costs, which are rapidly reversing, the Fed is concerned that strong wage growth could fuel persistent increases in services prices and overall inflation, he added.
“The Federal Open Market Committee will continue to increase the fed funds rate in early 2023 until it becomes more apparent that the job market is cooling, and wage growth and services inflation are slowing to more sustainable paces,” he added.
The Fed’s latest economic projections that were released last week showed that board members were expecting inflation to remain slightly higher for longer than previously forecast. Fed board members now expect PCE inflation to end 2023 at 3.1% and core PCE to finish next year at 3.5%, above the central bank’s target rate of 2%.
A separate Commerce Department report released Friday showed that new orders for manufactured goods tumbled 2.1% in November, the biggest monthly drop since the onset of the pandemic.
Transportation equipment, specifically new orders for non-defense aircraft and parts, drove the decline, according to the report. Excluding transportation, new orders increase 0.2%.
Shipments increased 0.2% in November, which followed a 0.4% increase in October.
“Core durable goods orders slowed but did not contract, reflecting growing unease about the economy,” Diane Swonk, chief economist for KPMG, tweeted Friday after the report’s release. “Manufacturing activity has begun to contract and prelim reading for December suggests it will contract further at year end. A cold winter expected for the manufacturing sector.
Inflation’s slow march downward has been welcome news to consumers as well, helping to perk up their economic sentiments during December, according to new data released Friday by the University of Michigan.
The final December reading for the index of consumer sentiment came in at 59.7 in December, up slightly from a preliminary measurement of 59.1 and November’s final reading of 56.8, according to data from the university’s Surveys of Consumers.
“Consumers clearly welcomed the recent easing of inflation,” Joanne Hsu, director of the Surveys of Consumers, said in a statement. “While sentiment appears to have turned a corner from its all-time low from June, consumers have reserved judgment about whether the trends will continue.”
She added: “Their outlook for the economy may have improved, but it remains relatively weak. The sustainability of robust consumer spending is contingent on continued strength in incomes and labor markets in the quarters ahead.”
The report showed the biggest improvement in sentiment about business conditions, while inflation expectations also improved by falling to 4.4% in December, the lowest reading in 18 months, according to the university. This is a key data point for the Federal Reserve. If consumers believe prices will remain high, that could factor into increased wage demands, which could cause businesses to raise prices.
Earlier this week, the Conference Board’s consumer confidence index – another measure of how consumers are feeling about the economy – landed at its highest measurement since April 2022.
Innovative MIT Passive Cooling System Works Without Electricity
By
Two samples of passive cooling devices were tested on the roof of MIT’s Building 1: On the left, a sample of the new system, combining evaporative cooling, radiative cooling, and insulation. On the right, a device using just evaporative cooling, for comparison testing. Credit: Courtesy of Zhengmao Lu
Relying on evaporation and radiation — but not electricity — the
The system combines radiative cooling, evaporative cooling, and thermal insulation in a slim package that could resemble existing solar panels. It can provide up to about 19 degrees
“This technology combines some of the good features of previous technologies such as evaporative cooling and radiative cooling,” Lu says. By using this combination, he says, “we show that you can achieve significant food life extension, even in areas where you have high humidity,” which limits the capabilities of conventional evaporative or radiative cooling systems.
It would also be useful in places that do have existing air conditioning systems in buildings. There, the new system could be used to significantly reduce the load on these systems by sending cool water to the hottest part of the system, the condenser. “By lowering the condenser temperature, you can effectively increase the air conditioner efficiency, so that way you can potentially save energy,” Lu says.
Although he says other groups have also been pursuing passive cooling technologies, “by combining those features in a synergistic way, we are now able to achieve high cooling performance, even in high-humidity areas where previous technology generally cannot perform well.”
Three layers of material make up the system, which collectively provide cooling as water and heat pass through the device. In practice, the device could resemble a conventional solar panel, but instead of generating electricity, it would directly provide cooling. For example, it could act as the roof of a food storage container, keeping the content cool. Another practical application would be using it to send chilled water through pipes to cool parts of an existing air conditioning system and improve its efficiency. Maintenance is minimal; all that’s required is adding water for the evaporation. Moreover, the water consumption is so low that this would only need to be done about once every four days in the hottest, driest areas, and only once a month in wetter areas.
Aerogel is used for the top layer. This material consists mostly of air enclosed in the cavities of a sponge-like structure made of polyethylene. Although it is highly insulating, it freely allows both water vapor and infrared radiation to pass through. The evaporation of water (rising up from the layer below) provides some of the cooling power, while the infrared radiation, taking advantage of the extreme transparency of Earth’s atmosphere at those wavelengths, radiates some of the heat straight up through the air and into space — unlike air conditioners, which spew hot air into the immediate surrounding environment.
Hydrogel is used for the next layer below the aerogel. It is another sponge-like material, but one whose pore spaces are filled with water rather than air. It’s similar to material currently used commercially for products such as cooling pads or wound dressings. This provides the water source for evaporative cooling, as water vapor forms at its surface and the vapor passes up right through the aerogel layer and out to the environment.
Below the hydrogel, a mirror-like layer reflects any incoming sunlight that has reached it, sending it back up through the device rather than letting it heat up the materials and thus reducing their thermal load. And the top layer of aerogel, being a good insulator, is also highly solar-reflecting, limiting the amount of solar heating of the device, even under strong direct sunlight.
“The novelty here is really just bringing together the radiative cooling feature, the evaporative cooling feature, and also the thermal insulation feature all together in one architecture,” Lu explains. The system was tested, using a small version, just 4 inches across, on the rooftop of a building at MIT, proving its effectiveness even during suboptimal weather conditions, Lu says, and achieving 9.3 °C of cooling (18.7 °F).
“The challenge previously was that evaporative materials often do not deal with solar absorption well,” Lu says. “With these other materials, usually when they’re under the sun, they get heated, so they are unable to get to high cooling power at the ambient temperature.”
The aerogel material’s properties are a key to the system’s overall efficiency, but that material at present is expensive to produce, as it requires special equipment for critical point drying (CPD) to remove solvents slowly from the delicate porous structure without damaging it. The key characteristic that needs to be controlled to provide the desired characteristics is the size of the pores in the aerogel, which is made by mixing the polyethylene material with solvents, allowing it to set like a bowl of Jell-O, and then getting the solvents out of it. The research team is currently exploring ways of either making this drying process more inexpensive, such as by using freeze-drying, or finding alternative materials that can provide the same insulating function at lower cost, such as membranes separated by an air gap.
While the other materials used in the system are readily available and relatively inexpensive, Lu says, “the aerogel is the only material that’s a product from the lab that requires further development in terms of mass production.” And he says that it’s impossible to predict how long that development might take before this system can be made practical for widespread use.
This work “represents a very interesting and novel system integration approach of passive cooling technologies,” says Xiulin Ruan, a professor of mechanical engineering at Purdue University, who was not associated with this research. Ruan adds, “By combining evaporative cooling, radiative cooling, and insulation, it has a better cooling performance and can be effective in a wider range of climates than evaporative cooling or radiative cooling alone. The work could attract significant practical applications, such as in food preservation, if the system can be made at reasonable cost.”
Reference: “Significantly enhanced sub-ambient passive cooling enabled by evaporation, radiation, and insulation” by Zhengmao Lu, Arny Leroy, Lenan Zhang, Jatin J. Patil, Evelyn N. Wang and Jeffrey C. Grossman, 20 September 2022, Cell Reports Physical Science.
DOI: 10.1016/j.xcrp.2022.101068
The research team included Lenan Zhang of MIT’s Department of Mechanical Engineering and Jatin Patil of the Department of Materials Science and Engineering.
MIT researchers invented cooling tech that doesn’t need electricity
Scientists at the Massachusetts Institute of Technology (MIT) have created a passive cooling tech that could revolutionize how we keep things cold. The new tech, which relies on a three-layer design, was showcased in a new press release. It only requires water, and researchers have used it to cool ambient temperatures by up to 19 degrees Fahrenheit.
The researchers published their findings in Cell Reports Physical Science. According to the study, the passive cooling tech relies on a three-layer setup that includes a solar reflector, an evaporator plus emitter, and insulation. The design allows heat to pass through while also cooling the water contained within.
The top layer of the device is made of an aerogel with air enclosed in multiple cavities. This insulating material allows water vapor and infrared radiation to pass through. The researchers outlined how it works in a press release from the university. The secondary layer is made of hydrogel. The cavities of this layer are where the water resides. Finally, the last layer is a mirror.
The researchers say the passive cooling tech works by reflecting light and infrared radiation back up through the two gel layers. This allows it to stave off heat that would otherwise pass to the storage box underneath the device. In humid conditions, the researchers say the device may allow food to be stored for up to 40 percent longer than without it.
This new passive cooling tech combines older methods – where people would dig holes and then store things underground to keep sunlight from warming them up. However, because it doesn’t require digging holes or building underground bunkers, this tech could open new doors to storing food and other items that require being kept at lower temperatures.
Of course, there are still some problems holding up any kind of product commercialization. That’s because the gel used in the device was created by MIT specifically for the experiment. And, unfortunately, it’s quite expensive to make from the sounds of things. If they can figure out a way to make aerogel both conducive to the tech and cheaper, though, this would be huge.
MIT has continued to deliver exceptional and intriguing tech and ideas. Earlier this year, scientists with MIT re-proposed an old theory on how to reverse climate change. They’ve even found a better way to boil water. This latest passive cooling tech is just one of many ideas the scientists and engineers at MIT continue to share with the world.
Chips drive highest Samsung Q2 profit since 2018, but demand cooling
SEOUL, July 7 (Reuters) – South Korea’s Samsung Electronics Co Ltd (005930.KS) turned in its best April-June profit since 2018 on Thursday, underpinned by strong sales of memory chips to server customers even as demand from inflation-hit smartphone makers cools.
Shares of the world’s largest memory-chip and smartphone maker closed up 3.2% after preliminary results were announced, versus a 1.8% rise in the wider market (.KS11).
Shares of other chipmakers, including rival SK Hynix (000660.KS) and the world’s biggest foundry TSMC (2330.TW), also rose as analysts said tight supply of certain chips could help offset slower demand that is driving down memory chip prices.
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Samsung posted an operating profit of 14 trillion won ($10.7 billion), up 11% from 12.57 trillion won a year earlier, just shy of a 14.45 trillion won SmartEstimate from Refinitiv.
Revenue for the second quarter rose 21% to 77 trillion won, in line with market estimates.
The strong quarter for Samsung comes at a time when other chipmakers have warned of a looming chip glut at customers who stocked up during the pandemic to meet higher demand from people working from home.
Chipmakers including Micron (MU.O) and Advanced Micro Devices (AMD.O) have also recently signalled waning demand as red-hot inflation squeezes spending. read more
“Memory chipmakers are expected to build inventory this year, keeping supply conservative, and hike shipments when prices rebound and demand recovers next year”, said Park Sung-soon, an analyst at Cape Investment & Securities.
Prices of specific DRAM chips, used in devices and servers, fell about 12% last month from a year ago, according to data provider TrendForce. Prices of NAND Flash chips, used for data storage, are also projected to fall as much as 5% in the July-September period from the previous quarter.
SMARTPHONE DEMAND WEAKENS
Rising inflation, concerns about a downturn in major markets, the war in Ukraine and China’s COVID-19 lockdowns have resulted in slowing smartphone sales, leaving server chip demand as the only bright spot, analysts said.
Samsung’s profits have been shielded as large U.S. tech firms such as Amazon (AMZN.O), Microsoft (MSFT.O), Alphabet’s (GOOGL.O) Google and Meta (META.O) that use a lot of data centre services kept buying chips to meet cloud demand, they added.
Making a case for strong server demand, Taiwanese contract electronics supplier and Apple iPhone maker Foxconn (2317.TW) on Monday raised its full-year outlook and said it was optimistic about the third quarter. read more
A strong dollar, which hit a 20-year high, may have also aided Samsung’s chip profits in the second quarter. read more
Samsung’s chip sales are made mainly in dollars, while it reports its profit in Korean won, so a firm greenback translates to higher chip earnings.
Estimated smartphone shipments by Samsung’s mobile business in the second quarter were about 62-64 million, about 5%-8% lower than a March estimate, Counterpoint Research said, as inflation hit smartphone demand.
Samsung shipped 74 million smartphones in the first quarter.
“This trend is the same for major global smartphone makers, although there is variance to some degree … In particular, the hit to the demand for low- and mid-end smartphones seems more severe,” said Jene Park, Senior analyst at Counterpoint.
($1 = 1,304.4400 won)
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Reporting by Joyce Lee and Heekyong Yang; Editing by Sayantani Ghosh and Himani Sarkar
Our Standards: The Thomson Reuters Trust Principles.
This Weird Star Survived a Supernova Only to Shine Even More Brightly Than Before
When it comes to going out with style, nothing comes close to the end of a white dwarf. Their thermonuclear self-destruction ranks among the most powerful explosions in the cosmos, forcing the star to wink out of existence in a blaze of glory.
At least, that’s the idea. A discovery confirms some white dwarfs fake their deaths with a lackluster performance, only to go on shining even brighter than before.
Ten years ago, supernova SN 2012Z was spotted in the nearby spiral galaxy NGC 1309, glowing briefly in a swan song that should, by all accounts, herald its annihilation.
Images of its home galaxy went back for years prior, so working out which star went bang simply required studying follow-up images to spot the now empty spaces.
“We were expecting to see one of two things when we got the most recent Hubble data. Either the star would have completely gone away, or maybe it would have still been there, meaning the star we saw in the pre-explosion images wasn’t the one that blew up,” says UC Santa Barbara astronomer Curtis McCully.
“Nobody was expecting to see a surviving star that was brighter. That was a real puzzle.”
As unexpected as it was, the observation wasn’t entirely without precedent, contributing to a growing pile of evidence that life after death might not be such an odd thing for white dwarf stars.
Once a star with our Sun’s mass squeezes its last dregs of helium into carbon and oxygen, it collapses into a dense, white-hot sphere the size of our Earth. Without the mass to build bigger elements, it simmers away, cooling over the eons until eventually dimming into a cold, black lump.
If such a depleted stellar core has a generous companion star orbiting nearby, life might go on a smidge longer as it siphons off a little extra gas.
At a critical point, however, all that extra mass risks pushing the carbon into fusion, sparking a runaway reaction that unleashes a tremendous amount of energy in a blink, tearing the star apart in what’s known as a Type Ia supernova.
Usually, there’s nothing of note left in the space once occupied by the white dwarf – just an expanding cloud of star guts drifting out into the cosmos, faintly glowing with residual radiation.
These specific blasts are so clockwork they all burn at roughly the same brilliance, making them handy for gauging distances across the Universe.
Yet not all explosions are so standard. The more common Type Iax supernova are less like fireworks and more like damp squibs, popping slowly in a comparatively dull whimper.
They might not even be all that destructive, with signs of high-density matter with hallmarks of a thick photosphere spotted in the aftermath of a handful of these less impressive supernovae.
(McCully et al., The Astrophysical Journal, 2022)
Above: Color images of NGC 1309 both before and after SN 2012Z. The left panel shows the Hubble Heritage (pre-explosion) image of NGC 1309. The top-middle panel shows a zoom-in on the position of the supernova from the pre-explosion image. The top-right shows SN~2012Z from the 2013 visit. The middle-bottom panel shows the location of SN~2012Z in the latest observations in 2016. The bottom-right panel shows the difference image between the pre-explosion images and the observations from 2016.
Finding SN 2012Z radiating furiously after its own supernova leaves little doubt that in some, if not many cases, white dwarfs can remain intact even after going thermonuclear.
Exactly why this particular star not only fell short of ripping itself apart but happened to come back even brighter is something of a mystery. The researchers behind the discovery speculate the blast merely stirred things up, allowing its material to settle back into a less dense, more puffed-up form.
With a larger volume, the cooling remains of the white dwarf would look even more radiant than ever.
“The implications for Type Ia supernovae are profound,” says McCully.
“We’ve found that supernovae at least can grow to the limit and explode. Yet the explosions are weak, at least some of the time. Now we need to understand what makes a supernova fail and become a Type Iax, and what makes one successful as a Type Ia.”
This research was published in The Astrophysical Journal.
Physicists Say They’ve Built an Atom Laser That Can Run ‘Forever’
A new breakthrough has allowed physicists to create a beam of atoms that behaves the same way as a laser, and that can theoretically stay on “forever”.
This might finally mean the technology is on its way to practical application, although significant limitations still apply.
Nevertheless, this is a huge step forward for what is known as an “atom laser” – a beam made of atoms marching as a single wave that could one day be used for testing fundamental physical constants, and engineering precision technology.
Atom lasers have been around for a minute. The first atom laser was created by a team of MIT physicists back in 1996. The concept sounds pretty simple: just as a traditional light-based laser consists of photons moving with their waves in sync, a laser made of atoms would require their own wave-like nature to align before being shuffled out as a beam.
As with many things in science, however, it is easier to conceptualize than to realize. At the root of the atom laser is a state of matter called a Bose-Einstein condensate, or BEC.
A BEC is created by cooling a cloud of bosons to just a fraction above absolute zero. At such low temperatures, the atoms sink to their lowest possible energy state without stopping completely.
When they reach these low energies, the particles’ quantum properties can no longer interfere with each other; they move close enough to each other to sort of overlap, resulting in a high-density cloud of atoms that behaves like one ‘super atom’ or matter wave.
However, BECs are something of a paradox. They’re very fragile; even light can destroy a BEC. Given that the atoms in a BEC are cooled using optical lasers, this usually means that a BEC’s existence is fleeting.
Atom lasers that scientists have managed to achieve to date have been of the pulsed, rather than continuous variety; and involve firing off just one pulse before a new BEC needs to be generated.
In order to create a continuous BEC, a team of researchers at the University of Amsterdam in the Netherlands realized something needed to change.
“In previous experiments, the gradual cooling of atoms was all done in one place. In our setup, we decided to spread the cooling steps not over time, but in space: we make the atoms move while they progress through consecutive cooling steps,” explained physicist Florian Schreck.
“In the end, ultracold atoms arrive at the heart of the experiment, where they can be used to form coherent matter waves in a BEC. But while these atoms are being used, new atoms are already on their way to replenish the BEC. In this way, we can keep the process going – essentially forever.”
That ‘heart of the experiment’ is a trap that keeps the BEC shielded from light, a reservoir that can be continuously replenished for as long as the experiment runs.
Protecting the BEC from the light produced by the cooling laser, however, while simple in theory, was again a bit more difficult in practice. Not only were there technical hurdles, but there were also bureaucratic and administrative ones too.
“On moving to Amsterdam in 2013, we began with a leap of faith, borrowed funds, an empty room, and a team entirely funded by personal grants,” said physicist Chun-Chia Chen, who led the research.
“Six years later, in the early hours of Christmas morning 2019, the experiment was finally on the verge of working. We had the idea of adding an extra laser beam to solve a last technical difficulty, and instantly every image we took showed a BEC, the first continuous-wave BEC.”
Now that the first part of the continuous atom laser has been realized – the “continuous atom” part – the next step, the team said, is working on maintaining a stable atom beam. They could achieve this by transferring the atoms to an untrapped state, thereby extracting a propagating matter wave.
Because they used strontium atoms, a popular choice for BECs, the prospect opens exciting opportunities, they said. Atom interferometry using strontium BECs, for example, could be used to conduct investigations of relativity and quantum mechanics, or detect gravitational waves.
“Our experiment is the matter wave analogue of a continuous-wave optical laser with fully reflective cavity mirrors,” the researchers wrote in their paper.
“This proof-of-principle demonstration provides a new, hitherto missing piece of atom optics, enabling the construction of continuous coherent-matter-wave devices.”
The research has been published in Nature.
Here’s a Glimpse at a Future Hothouse Earth if Greenhouse Gasses Aren’t Curbed
Throughout our planet’s history, Earth has fluctuated between a hothouse and an icehouse.
Today, our home is supposed to be in a period of global cooling, but human emissions of greenhouse gasses are reversing that natural trend at a rapid and unprecedented rate.
One of the last times Earth went from an icehouse to a hothouse this quickly and dramatically, about 304 million years ago, our planet experienced major upheaval.
During the Kasimovian–Gzhelian boundary (KGB), atmospheric carbon levels doubled in roughly 300,000 years, from around 350 parts per million to 700 ppm. Now, new research suggests about 23 percent of the seafloor during this time were deprived of oxygen.
The findings are based on a fresh analysis of trace elements in a slab of ancient black shale in South China. The isotopes of carbon and uranium within this rock suggest that on top of global warming, rising sea levels, and melting glaciers, we also need to worry about ocean anoxia.
Anoxia is defined as a lack of oxygen. It can occur with climate change because when ice caps melt and add fresh water to the ocean surface, it obstructs atmospheric oxygen from dissolving and circulating in the sea.
Under extreme anoxic conditions, life in the ocean struggles to survive. Even areas with low oxygen, called hypoxia, are known as ‘dead zones’.
The new results are supported by previous research on ancient bedrock in South China, which found major losses to biodiversity in the sea during the KGB boundary.
When modeling these ancient climate changes, the authors of the current study realized the importance of timing.
“If you raised CO2 by the same amount in a greenhouse world, there isn’t much effect, but icehouses seem to be much more sensitive to change and marine anoxia,” explains sedimentary geochemist Isabel Montañez from the University of California, Davis.
In other words, if human emissions had rapidly increased during a natural period of global warming, instead of global cooling, ocean anoxia wouldn’t be nearly as big a threat.
Perhaps the reason has to do with the fact that greenhouse gasses in a hothouse world are already high, so emissions don’t have as strong a melting effect on ice sheets and permafrost.
But during a period of global cooling, there are more ice sheets and glaciers trapping fresh water, ready to infiltrate the surface of the ocean and obstruct oxygen dissolving.
Researchers suspect the massive release of carbon that caused climate change between 290 and 340 million years ago was probably stimulated by volcanic eruptions.
Extensive wildfires would then have added even more carbon to the atmosphere, as would permafrost melt.
These are just ideas, though. Researchers were unable to trace the exact cause of carbon emissions during the KGB, but their results show a clear spike in greenhouse gas emissions, followed by extensive sea level rise and anoxia.
“Massive carbon release with abrupt warming has occurred repeatedly during greenhouse states, and these events have driven episodes of ocean deoxygenation and extinction,” the authors write.
“Records from these paleo events, coupled with biogeochemical modeling, provide clear evidence that with continued warming, the modern oceans will experience substantial deoxygenation.”
The study was published in PNAS.