Friday, May 17, 2024

SPACE

James Webb telescope spots 2 monster black holes merging at the dawn of time, challenging our understanding of the universe


Brandon Specktor
Thu, May 16, 2024 

This image shows the environment of the galaxy system ZS7 as seen by the James Webb Space Telescope. A zoomed-in look at the merging black hole system is inset in yellow.


Astronomers have used the James Webb Space Telescope (JWST) to detect the most distant pair of colliding black holes in the known universe. The cosmic monsters — each estimated to be as massive as 50 million suns — have been detected more than 13 billion light-years away, at a time just 740 million years after the Big Bang.

While not the biggest or oldest black holes ever detected, the merging pair have still managed to grow bafflingly large for such an early time in the universe's history, the study authors said in a European Space Agency (ESA) statement. This discovery further challenges leading theories of cosmology, which fail to explain how objects in the universe's infancy could grow so large, so fast.

"Our findings suggest that merging is an important route through which black holes can rapidly grow, even at cosmic dawn," the study’s lead author Hannah Übler, a researcher at the University of Cambridge, said in the statement. "Together with other Webb findings of active, massive black holes in the distant Universe, our results also show that massive black holes have been shaping the evolution of galaxies from the very beginning."

Black holes are extraordinarily massive objects with a gravitational pull so strong that nothing, not even light, can escape their clutches. They are thought to form when massive stars collapse in supernova explosions, and they grow by endlessly swallowing up the gas, dust, stars and other matter in the galaxies that surround them.

The hungriest, most active black holes may reach supermassive status — bulking up to be anywhere from a few hundred thousand to several billion times the mass of the sun. One key way that supermassive black holes may reach such gargantuan sizes is by merging with other large black holes in nearby galaxies — a phenomenon that's been detected at various times and places throughout the universe.

Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed?

The new discovery comes courtesy of JWST's powerful NIRCam infrared instrument, which can detect the light of ancient objects across vast cosmic distances and through obscuring clouds of dust.

In the new study, published Thursday (May 16) in the Monthly Notices of the Royal Astronomical Society, researchers trained the JWST's infrared cameras on a known black hole system called ZS7, located in an early epoch of the universe known as cosmic dawn. Previous observations showed that the system hosts an active galactic nucleus —- a feeding, supermassive black hole at the galaxy's center, which emits bright light as hot gas and dust swirls into the black hole's maw.

This image shows the location of the galaxy system ZS7 as seen through the James Webb Space Telescope.

Detailed observations with JWST revealed the motion of a dense cloud of gas around the black hole — suggesting it was actively growing — and also pinpointed the approximate location of a second black hole located very close by, likely in the process of merging with the first.

"Thanks to the unprecedented sharpness of its imaging capabilities, Webb also allowed our team to spatially separate the two black holes," Übler said. The team pegged one of the black holes at about t 50 million solar masses; the second black hole, which is "buried" in the dense cloud of gas, likely has a similar mass to its neighbor, but the researchers couldn't get a clear enough view of its radiation to say for sure.

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This exceptionally ancient pair of merging black holes adds further weight to the idea that black holes had a huge impact on the evolution of galaxies in the infant universe, growing faster than current theories of cosmology can explain.

The legacy of these massive mergers can still be felt today in the form of gravitational waves — ripples in the fabric of space-time that were first predicted by Albert Einstein, and that were recently confirmed to be a ubiquitous feature of the universe — that spread across space when massive objects like black holes and neutron stars collide.

The ripples released by these faraway, colliding monsters are too faint to be picked up by current gravitational wave detectors on Earth, the study authors added. However, next-generation detectors that will be deployed in space, such as ESA's planned LISA detector (scheduled to launch in 2035), should be able to detect even the most distant ripples from merging black holes. The new results suggest that evidence of these ancient mergers may be far more plentiful than previously thought.


Sun releases the strongest flare in current cycle from the same region that triggered auroras this weekend

Kaila Nichols and Taylor Ward, CNN
Wed, May 15, 2024


After causing the dazzling waves of aurora borealis this weekend, our Sun isn’t done yet: The strongest solar flare of the current solar cycle occurred Tuesday afternoon, according to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center.

The flare – deemed an X8.7, with the X-class denoting the most intense flares possible – came from the same region that triggered the geomagnetic storm and stunning display of auroras, or Northern Lights, around the world. That storm was the most extreme geomagnetic storm since 2003, the center said.

“A flare is an eruption of energy from the Sun that generally lasts minutes to hours. Flares of this magnitude are not frequent,” the center noted.

Tuesday’s intense flash of ultraviolet light was photographed by NASA’s Solar Dynamics Observatory, which said the flare peaked at 12:51 p.m. ET.

Solar flares usually take place in active regions of the Sun that include the presence of strong magnetic fields. They can impact radio, power grids and communications. Users of high frequency radio signals may experience temporary or complete loss of signal.

However, due to the Sun’s rotation, the sun spot in question is no longer directing this energy in the Earth’s direction, which will minimize impacts.

Flares can also pose threats to astronauts and spacecraft – though NASA found there was no risk to astronauts aboard the International Space Station last week.

Scientists on Friday issued a severe geomagnetic storm watch for the first time in nearly 20 years, advising people to prepare for power outages during last week’s solar storm. The White House was also tracking the event for any potential impacts.

“The Sun’s activity waxes and wanes over an 11-year period known as the solar cycle,” the Solar Dynamics Observatory said on X. “Solar cycle 25 began in December 2019 and is now approaching solar maximum — a period when eruptions like this one become more common.”

This cycle will reach its peak between late 2024 and early 2025. Researchers have been seeing more intense solar flares as we inch closer to the cycle’s end.



How to Prepare for the Next Solar Storm

Jeffrey Kluger
TIME
Wed, 15 May 2024 



It has been a season of sky pageants. March 24 and 25 saw a lunar eclipse across the Americas, Europe, and North and East Asia. April 8 featured the total solar eclipse in North America. March and April also brought the appearance of the evocatively named Devil Comet. And last weekend, earthlings were treated to a spectacular light show when a geomagnetic explosion on the sun, known as a coronal mass ejection, produced a colorful display of the aurora borealis, a phenomenon usually limited to the north polar region, but visible this time around as far south as Alabama in the U.S. and at similar latitudes around the world.

Coronal mass ejections produce not just spectacle, but potentially deadly mischief. When the energy from the sun collides with Earth, it can disrupt satellites, send GPS systems awry, knock power plants offline, and shut down telecommunications. Like hurricanes, solar storms are ranked in five categories by the National Oceanic and Atmospheric Administration (NOAA), from minor to moderate to strong to severe to extreme.

On May 12, NOAA issued a rare severe-to-extreme warning for the unfolding event, though even at its peak, from May 10 to 12, there were no reports of power or satellite disruption. But if the Earth dodged a bullet this time, we face a potentially rough year or so, as the sun goes through one of its cycles of peak activity.

So what’s going on out there, how great is the danger to us here on Earth, and how can we prepare?
What causes solar storms?

In the same way the Earth has its seasons, the sun does too. Solar seasons play out not over the course of months, however, but in 11-year cycles that produce times of high activity, known as the solar maximum, and low activity known as the solar minimum. The cycles are due to the fact that the sun is not solid, which means that different parts of its surface rotate at different rates—taking 25 days to complete a single rotation at the equator and 33 days at the poles. This causes the sun’s magnetic field to become tangled, slowly building up energy until it snaps. When that happens, the north and south magnetic poles switch places with each other, releasing the energy that creates the solar maximum. Once that energy is expended, the sun returns to a less volatile solar minimum.

One telltale sign of high solar activity is sunspots, small patches of twisted magnetic fields on the sun. The greater the number of spots, the greater the solar volatility. The current eruption was associated with a sunspot 16 times the diameter of Earth, and gave off billions of tons of plasma—superheated gas made up of charged particles.

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Not every solar maximum or solar minimum is equal, however. “The main cycle of the sun is the 11-year one, but people have noticed longer trends in the sunspot activity,” says Michael Liemohn, professor of climate and space sciences and engineering at the University of Michigan. “There seems to be a century-long cycle for which the number of sunspots at solar maximum is smaller for a cycle or two and then returns to a more normal level.”

The last period of solar maximum, which ended about ten years ago, was at the lower end of the energy spectrum. The one that ended 20 years ago was higher. “We expect this current solar maximum to be bigger than the previous one, and more similar to the solar activity peak 20 years ago,” says Liemohn.
How do coronal mass ejections endanger Earth?

The best way to understand the effect solar storms have on our planet is to think of the atmosphere as akin to the gas in a fluorescent light bulb. In the bulb, Liemohn explains, electrodes at either end accelerate electrons, which interact with the gas, imparting energy to it and causing it to give off light. High in the atmosphere—50 to 200 miles up—a similar process creates the aurora. Closer to the surface of the Earth, the effect is not so benign.

“Like in the bulb, there is an electric current associated with the fast electrons, and these space currents can induce other electric currents in … conducting loops here on the ground,” says Liemohn. “The loops have to be very long, many miles, but high voltage power lines are susceptible to this effect.”

Damage to satellites is more direct and done in a number of ways. As NASA’s Goddard Space Flight Center explains, geomagnetic storms heat the outer atmosphere, causing it to expand. This increases the drag on satellites and can degrade their orbits. The charged particles streaming from the sun during a solar storm can also penetrate a satellite or electrify its surface, damaging its components. The problem is especially acute in satellites in high orbits, more than 22,000 miles above the Earth—which is the altitude at which most communications satellites fly.

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Crewed spacecraft like the International Space Station orbit much lower—typically about 250 miles up. That affords astronauts some protection from the Earth’s magnetosphere—which shields us from solar and cosmic rays on the ground. Still, astronauts receive more of a radiation dose than earthbound people and animals do, especially during a solar storm. The station or spacecraft themselves provide additional protection—but an unprotected astronaut on the surface of the moon or Mars would be in serious trouble during a solar storm. According to Space.com, a coronal mass ejection “shock wave” would expose the astronaut to the equivalent of 300,000 simultaneous chest x-rays, much more than the 45,000 that would prove lethal.
Getting ready for the next one

Typically, a solar storm takes a day or so to reach and pass Earth. The recent one lasted several days, Liemohn explains, because the sun released several storms in quick succession. “Earth is in the recovery phase of the storm now, which will last a few more days,” he said on May 12. “But now the aurora will be confined to its usual location at higher latitudes, across Alaska and Canada.”

More big storms are likelier than not during this powerful solar maximum. The solar weather could take until mid 2025 to start to subside, according to NOAA. So how can we prepare?

In 2019, Congress took a stab at hardening America’s defenses against space weather events when it passed the PROSWIFT Act, for Promoting Research and Observations of Space Weather to Improve the Forecasting of Tomorrow. Under the act, Washington empowered NOAA, NASA, the National Science Foundation, industry, academia and more to research how to prepare for adverse space weather events and to prioritize appropriate funding to that end.

“Basically,” says Daniel Welling, assistant professor in climate and space sciences at the University of Michigan, “the law is to have these bodies advise the nation on how to proceed in trying to understand and set benchmarks for space weather forecasting.”

At the moment, that’s not easy to do. For one thing, space weather is still something of a black box for researchers. For another, even if we could predict it as reliably as we can predict terrestrial weather, the U.S. power grid is so sprawling and regionalized that it’s hard to put protocols in place to protect everything.

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A proof-of-concept example of what that kind of command and control system would look like, however, does exist in New Zealand.

Just over a year ago, Welling worked with a team at Transpower, the owner and operator of the country’s national grid,

to model an extreme solar storm estimate and then change the grid configuration until it was stable. That was distilled down to a PDF procedure that sits on the desks of the Transpower operators. “They activated it this [past] weekend,” says Welling, “which is really cool.”

But a nation of 5.1 million covering a land mass of 103,500 square miles is different from a nation like the U.S., with its 333 million people and its 3.8 million square miles. And if a grid-killing storm hit, our power systems would likely go down. That’s not for lack of machinery and protocols in development, however. Power plant transformers operate on alternating current, but during solar storms may receive surges of direct current.

“Those transformers are not meant to handle that, so they can heat up, sometimes quite quickly,” says Welling.

A piece of hardware known as a geomagnetically induced current (GIC) blocker could be installed on the transformers to protect them from destructive pulses of power. The problem is the GIC blockers are still in development, and when they are installed, they can have what Welling calls a Whac-A-Mole effect. “You shut down the current [from the solar storm] over here, and it doubles over there,” he says.

That leaves transformers vulnerable—and vulnerable transformers are a very bad thing. “Transformers are the size of your living room, they’re custom-made and they’re shipped from overseas,” says Welling. If they are damaged or destroyed during a storm, it can take “weeks or longer to recover,” he adds.

Managing potential satellite damage is easier. One of the big risks here is phantom commands that cause the satellites to behave anomalously. The solution is to send them repeated “spam commands,” basically reminding them over and over again simply to continue functioning as they’re supposed to. Careful monitoring of trajectory can allow operators to fire the satellites’ thrusters in appropriate bursts, preventing orbits from decaying due to atmospheric drag.

Both oil pipelines and railroad systems can present problems as well since any long, metal, ground-based conductor can carry current during a geomagnetic storm. In the case of pipelines, there’s not much controllers can do but monitor them, looking for damage that can be done by the current. In the case of trains, says Welling, railway traffic controllers know not to trust automatic signals during a geomagnetic storm, and will instead take over manually. A similar rule applies to the oil industry and some aspects of the military that are heavily dependent on GPS systems.

“Those sectors will suspend operations until they get the all clear,” Welling says.

Air traffic controllers must also react, diverting airplanes from places that are experiencing communications blackouts, or grounding planes entirely if the absence of comms is more global. And passenger health will call for avoiding areas where high levels of dangerous radiation are present.

Last weekend, says Welling, “there were flights that normally fly over the pole being diverted to lower latitudes because of the radiation risk.”

For now, these decidedly imperfect protocols are the best measures the U.S. and most of the rest of the world have. Not only do better preventive and corrective solutions have to be developed, but the business of space weather prediction has to improve dramatically. And that could take a lot of time.

“There’s this saying that space weather is 50 years behind meteorology in terms of forecasting and statistics,” says Welling. “The events of [last] weekend really made that saying resonate with me.”


Thisgiant gas planet is as fluffy and puffy as cotton candy

MARCIA DUNN
Tue, 14 May 2024


This illustration provided by NASA depicts the planet WASP 193-b. Scientists reported Tuesday, May 14, 2024, that the exoplanet has such low density for its size that it's the consistency of cotton candy. (NASA via AP)


CAPE CANAVERAL, Fla. (AP) — Astronomers have identified a planet that’s bigger than Jupiter yet surprisingly as fluffy and light as cotton candy.

The exoplanet has exceedingly low density for its size, an international team reported Tuesday. The gas giants in our solar system — Jupiter, Saturn, Uranus and Neptune — are much denser.

“The planet is basically super fluffy” because it's made mostly of light gases rather than solids, lead author Khalid Barkaoui of Massachusetts Institute of Technology said in a statement

Scientists say an outlier like WASP-193b is ideal for studying unconventional planetary formation and evolution. The planet was confirmed last year, but it took extra time and work to determine its consistency based on observations by ground telescopes. It's thought to consist mostly of hydrogen and helium, according to the study published in Nature Astronomy.

The planet is located some 1,200 light-years away. A light-year is 5.8 trillion miles. It's the second-lightest exoplanet found so far based on its dimensions and mass, according to the researchers.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.


Scientists prove that plunging regions exist around black holes in space

Nina Massey, PA Science Correspondent
Wed, 15 May 2024



Scientists have proven one of Einstein’s theories, finding evidence that a plunging-region around black holes not only exists, but also exerts some of the strongest gravitational forces yet identified in the galaxy.

Einstein’s theory states that it is impossible for particles to safely follow circular orbits when close to a black hole.

Instead they rapidly plunge towards the object at close to the speed of light – giving the plunging region its name.


Experts say the findings show matter responding to gravity in its “strongest possible form”.

The new study focused on this region in depth for the first time, with Oxford University Physics researchers using X-ray data to gain a better understanding of the force generated by black holes.

Dr Andrew Mummery, of Oxford University Physics, who led the study, said: “What’s really exciting is that there are many black holes in the galaxy, and we now have a powerful new technique for using them to study the strongest known gravitational fields.”

He added: “Einstein’s theory predicted that this final plunge would exist, but this is the first time we’ve been able to demonstrate it happening.

“Think of it like a river turning into a waterfall – hitherto, we have been looking at the river. This is our first sight of the waterfall.”

“We believe this represents an exciting new development in the study of black holes, allowing us to investigate this final area around them.

“Only then can we fully understand the gravitational force.

“This final plunge of plasma happens at the very edge of a black hole and shows matter responding to gravity in its strongest possible form.”

Researchers say that there has been much debate between astrophysicists for many decades as to whether the so-called plunging region would be detectable.

The Oxford team spent the last couple of years developing models for it and, in the study just published, demonstrate its first confirmed detection found using X-ray telescopes and data from the international space station.

The study, published in the Monthly Notices of the Astronomical Society, focused on smaller black holes relatively close to Earth, using X-ray data gathered from space-based telescopes.

Later this year, a second Oxford team hopes to move closer to filming first footage of larger, more distant black holes.

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