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This week’s news roundup explores how the brain is affected by pregnancy, the way “scuba diving” lizards breathe underwater, and much more.

Find out what's going on at the International Space Station.

The Sentinel-1B satellite, the second satellite of the Copernicus Sentinel-1 mission, completed its disposal process – which included lowering its orbit and passivating its systems to ensure re-entry into Earth’s atmosphere within 25 years.

This careful operation highlights the European Union’s and ESA’s commitment to space safety and sustainability and provides valuable experience for the disposal of current and future spacecraft.

CAPTCHA tests are supposed to distinguish humans from bots, but an AI system mastered the problem after training on thousands of images of road scenes

CAPTCHA tests are supposed to distinguish humans from bots, but an AI system mastered the problem after training on thousands of images of road scenes

A gravitational lens is the ultimate funhouse mirror of the Universe. It distorts the view of objects behind them but also supplies amazing information about distant galaxies and quasars. Astronomers using Hubble Space Telescope (HST) recently released a new image of one of these weird apparitions called “The Carousel Lens”. It’s a rare alignment of seven background galaxies that all appear distorted by an intervening galaxy cluster.

According to Berkeley Lab senior scientist David Schlegel, this gravitational lens is a great find for astronomers. “This is an amazingly lucky ‘galactic line-up’—a chance alignment of multiple galaxies across a line-of-sight spanning most of the observable universe,” he said. “Finding one such alignment is a needle in the haystack. Finding all of these is like eight needles precisely lined up inside that haystack.”

The Carousel Lens was uncovered in Dark Energy Survey data a few years ago. Now astronomers are zeroing in on it to measure its mass and the effects on the images of more distant galaxies. This gravitational lens alignment of seven galaxies and a foreground galaxy cluster could well provide new insights into the early Universe via the high-redshift galaxy sources, the properties of the lensing cluster, and unanswered questions in cosmology.

An example of the Carousel gravitational lens found in the DESI Legacy Surveys data. There are four sets of lensed images in DESI-090.9854-35.9683. They correspond to four distinct background galaxies — from the outermost giant red arc to the innermost bright blue arc. All of them appear gravitationally warped — or lensed — by the orange galaxy at the very center. Deconstructing the Carousel Gravitational Lens

Typical large-scale gravitational lenses in the Universe consist of a “lensing object” and more distant objects behind it. Generally, those distant objects are galaxies and quasars. (Small-scale gravitational lenses occur when a planet passes in front of its star, for example.) However, the Carousel Lens is more “cosmic” in nature, covering objects millions of light-years apart. In particular, the cluster doing the lensing is about 5 billion light-years from Earth. It’s also designated as DESI-090.9854-35.9683 and has at least four large galaxy members as well as several other possible cluster members.

The Carousel lenses at least seven distant galaxies. They lie anywhere from 7.62 to 12 billion light-years away from Earth. Their alignment with the lensing cluster resulted in multiple images of each of the more distant galaxies. Their shapes are the result of the “funhouse mirror” effect that stretches their apparitions. The galaxy labeled “4a, 4b, 4c, 4d” actually forms a nearly perfect “Einstein Cross”, which shows the symmetrical distribution of mass in the lens.

The Carousel is a great example of a “strong lens” in the Universe, according to Xiaoshang Huang, who is part of the team at Berkeley studying it. “Our team has been searching for strong lenses and modeling the most valuable systems,” said Huang. “The Carousel Lens is an incredible alignment of seven galaxies in five groupings that line up nearly perfectly behind the foreground cluster lens. As they appear through the lens, the multiple images of each of the background galaxies form approximately concentric circular patterns around the foreground lens, as in a carousel. It’s an unprecedented discovery, and the computational model generated shows a highly promising prospect for measuring the properties of the cosmos, including those of dark matter and dark energy.”

The Carousel Lens as seen by the HST marked up by the galaxies. The “L” indicators near the center (La, Lb, Lc, and Ld) show the most massive galaxies in the lensing cluster. Seven unique galaxies (numbered 1 through 7) – located an additional 2.6 to 7 billion light years beyond the lens – appear in multiple, distorted “fun-house mirror” iterations (indicated by each number’s letter index, e.g., a through d), as seen through the lens. (Credit: William Sheu (UCLA) using HST data.) What Makes this Lens So Special?

In their recently released paper, Schlegel, Huang, and others described modeling the Carousel Lens to understand its structure. They point out that it shows nearly every lensing configuration that astronomers see in such apparitions. There are various arcs, diamond shapes, the Einstein Ring, and double lensing.

The big spread of distances between the lens itself and the galaxies it’s distorting also presents some interesting cosmological areas of study. In particular, the science team hopes to do more spectral studies to understand the lensing cluster’s matter distribution. At least seven lensed sources will help constrain the amount of matter in the cluster and aid in understanding the amounts of dark and baryonic matter in such systems.

In addition to matter distribution, the team can also use this lensing system as a way to understand the characteristics of the distant lensed sources. This is important because the most distant ones give insight into conditions in their various epochs of cosmic history. For example, source 7 is an interesting “nearby” source that could be a very high-redshift “quiescent” galaxy. It appears to be very “red” in infrared measures and others of this sort have been observed by HST. Source 7 could be an efficient example of what’s called “early galaxy quenching”.

That occurs when star formation shuts down and the galaxy becomes quiescent. There are several ways that could happen, but the most common is some kind of feedback loop between the central supermassive black hole and outlying regions. This could occur as a result of galaxy mergers, for example, which were very common in the early Universe. The Carousel Lens (and others of its type) provides a special way to study that epoch of cosmic history and the events that shaped the galaxies we see today.

For More Information

Magnifying Deep Space Through the ‘Carousel Lens
The Carousel Lens: A Well-modeled Strong Lens with Multiple Sources Spectroscopically Confirmed by VLT/MUSE

Gravitational lens found in the DESI Legacy Surveys data

The post This Might Be the Best Gravitational Lens Ever Found appeared first on Universe Today.

Solar flares are a fascinating thing and have a profound effect on what astronomers refer to as “space weather.” These events vary with the Sun’s 11-year solar cycle, releasing immense amounts of radiation across the electromagnetic spectrum (from extreme ultraviolet to X-rays) into space. The effects of flares have been observed since time immemorial, which include aurorae at high latitudes (Aurora Borealis and Australis), but have only been the subject of study and prediction for about a century and a half. Still, there is much that remains unknown about these dramatic events.

For instance, flares are known to affect the Sun’s atmosphere, from the visible surface (photosphere) to its outermost layer (corona). However, there are still questions about how these events influence the lower layers of the atmosphere. In a recent study led by the University of Colorado, Boulder, a team of researchers documented the rotation of two very small sunspots of the Sun’s surface (pores) using the Daniel K. Inouye Solar Telescope (DKIST) at Mauna Kea. These pores were linked to a less powerful flare and moved in a way that has never been observed, suggesting that the dynamics of the Sun’s atmosphere are more complex than previously thought.

The study was led by Rahul Yadav, a Research Scientist from the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado, Boulder (UC Boulder). He was joined by colleagues from UC Boulder’s Department of Astrophysical and Planetary Sciences, the U.S. National Science Foundation’s (NSF) National Solar Observatory (NSO), and the Institute of Solar-Terrestrial Physics of SB RAS. The paper that details their findings, “Photospheric Pore Rotation Associated with a C-class Flare from Spectropolarimetric Observations with DKIST,” recently appeared in the Astrophysical Journal Letters.

The NSO Daniel K. Inouye Solar Telescope atop Mauna Kea, Hawaii. Credit: NSF/NSO/AURA

Solar flares are thought to occur when stored magnetic energy in the Sun’s atmosphere accelerates charged particles in the surrounding plasma. They occur in active regions and are often accompanied by a significant amount of plasma being ejected into space – a Coronal Mass Ejection (CME) – and the release of accelerated particles – a Solar Particle Event (SPE). These can play havoc with satellites in Earth’s orbit, and interfere with radio antennas and electronic grids on the surface, which is why scientists are interested in learning more about them.

Flares are classified according to their strength: B-class is the weakest, C and M-class are slightly more energetic, and X is the strongest. Previous studies have shown how intense solar flares can lead to large sunspots rapidly rotating and distorting active regions on the Sun’s surface. But as Dr. Yadav explained in an NSO press release, what they observed was quite unexpected. “[T]his study marks the first time that such rotation has been observed on a smaller scale—less than 2,000 kilometers [~1,245 mi] across—associated with a less intense C-class flare,” he said.

In addition, previous observations have found that rotational movements of sunspots occur directly at the flare ribbon, where the most intense emissions occur during a flare event. This time, the team observed a pre-flare rotation located a short distance from the flare ribbon, which suggests that the coupling between different layers of the Sun’s atmosphere during flares may be more complex than previously thought. Yadav and his colleagues suggest that the process they observed is driven by changes in the Lorentz force caused by interactions between solar charged particles (aka. solar wind) and its magnetic fields.

As Prof. Maria Kazachenko, an NSO scientist and co-author of the study, explained:

“As the magnetic field lines in the corona reorganize, they could induce changes in the lower atmosphere, leading to the observed rotation. This discovery adds a new dimension to our understanding of the complex magnetic interactions that occur during solar flares.”

This animation shows the temporal evolution of a solar flare region and the surrounding sunspots/pores as observed by the VBI instrument on the Inouye Solar Telescope. Credit: NSO–NSF

The unique observations the team made using the Inouye telescope offer new insights into the mechanisms through which solar flares influence the lower layers of the Sun’s atmosphere. For example, past observations have revealed much about sunspot rotations that occurred during more powerful flares (M—or X-class). However, the Inouye data revealed that similar rotational movements can occur with less intense flares and on smaller scales. These findings could lead to new research avenues and help refine our models of solar activity.

This will have implications for the growing constellations of telecom, research, internet, and Earth observation satellites in Earth’s orbit. Predicting space weather, which affects everything in the Solar System to the very edge of the Heliosphere, is also important for long-duration missions in space. For astronauts working on the Moon and Mars and transiting through deep space, knowing more about flare activity will help mitigate the risk of radiation exposure.

Further Reading: NSO, AJL

The post High-Resolution Images of the Sun Show How Flares Impact the Solar Atmosphere appeared first on Universe Today.

Why does this large crater on Mercury have two rings and a smooth floor?

When you get close to a black hole, things can get pretty intense. The tremendous gravity can squeeze gas to ionizing temperatures, and fierce magnetic fields can accelerate plasma into jets speeding at nearly the speed of light. That’s a lot of power, and wherever there is power someone will figure out how to harness it.

Back in 1969 Roger Penrose noted that you could theoretically extract energy from a black hole simply by dumping garbage into it. The idea was to pack a spaceship full of junk, fly really close to a black hole so that you travel within the region of strongly twisted space known as the ergosphere, then simply dump your trash. The trash gets consumed by the black hole and your spaceship gets a boost of energy. No need to reduce, reuse, recycle, just toss it down the cosmic hole.

How to turn trash into energy. Credit: Atomic Rockets, adapted from Misner, Thorne and Wheeler

While this should work in principle, the engineering needed to carry it off would be challenging, and harnessing energy from a fast-moving rocket wouldn’t be very efficient. Fortunately there should be another way, just using electromagnetic waves. In 1971 Yakov Zeldovich demonstrated how a rotating black hole could amplify electromagnetic waves. Essentially if you beam light toward a rotating black hole, some of the light will be ampified due to the frame dragging of gravity.

At least in theory.

Therein lies the problem. While all of this is theoretically sound, we don’t have a spare black hole lying around to prove it. Luckily the Zeldovich effect works for more than just black holes. Zeldovich showed that the effect should work for any rotating body that absorbs a bit of the energy aimed at it. So you should be able to bounce light against a rotating cylinder and see the effect. No black hole needed. The only problem is that the cylinder would need to rotate at relativistic speeds and the effect would be tiny. Then in 2020 a team showed how a similar effect worked with sound waves. They beamed low-frequency sound waves into an absorptive rotating disk and measured an increase in acoustic energy, proving the Zeldovich effect worked for sound.

Measuring the electromagnetic Zeldovich effect. Credit: Braidotti, et al

Now the team is back with a new paper showing the effect with electromagnetic waves.[^4] The way they did it was to adapt a resonant circuit. The circuit could focus an oscillating magnetic wave through a through an aluminum cylinder. By itself the cylinder would act as a simple resistor and dampen the magnetic field, but when the team rotated the cylinder in a particular way the magnetic field was amplified just as Zeldovich predicted. Since aluminum isn’t magnetic, the isn’t due to some dynamo effect. Thus the team could demonstrate it is a new effect.

So we now know rotating bodies, including black holes, can amplify electromagnetic fields. What’s also interesting about this experiment is how surprisingly straight forward it is. The design is similar to an induction generator used in wind turbines. The experiment could have been done decades ago, it’s just that no one had thought of it before. Sometimes the answer to a scientific question is right in front of you.

Reference: Braidotti, M. C., et al. “Amplification of electromagnetic fields by a rotating body.” Nature Communications 15.1 (2024): 5453.

The post Researchers Mimic Extracting Energy From Black Holes in the Lab appeared first on Universe Today.

SpaceX's Crew-9 mission to the International Space Station on Sept. 26 will be a rescue mission of sorts, bringing up empty seats for two NASA astronauts currently in space without a ride home.

Canada's Avro Arrow supersonic jet was suddenly canceled in 1959, a controversial decision that benefited NASA. How is Canada preserving the few pieces of the aircraft that remain?

A NASA astronaut and two record-setting Russian cosmonauts are set to head back to Earth on Monday (Sept. 23), and you can watch their homecoming live.

The autumnal equinox brings fall to the Northern Hemisphere today as the sun passes directly over the equator at noon. But are day and night actually equal length today?

Earth’s average global temperatures have been steadily increasing since the Industrial Revolution. According to the National Oceanic and Atmospheric Agency (NOAA), Earth has been heating up at a rate of 0.06 °C (0.11 °F) per decade since 1850 – or about 1.11 °C (2 °F) in total. Since 1982, the average annual increase has been 0.20 °C (0.36 °F) per decade, more than three times as fast. What’s more, this trend is projected to increase by between 1.5 and 2 °C (2.7 to 3.6 °F) by mid-century, possibly more! This is a direct consequence of burning fossil fuels, which has increased exponentially since the mid-19th century.

Depending on the extent of temperature increases, the impact on Earth’s habitability could be catastrophic. In a recent study, a team of scientists examined how temperature increases are a long-term issue facing advanced civilizations and not just a matter of fossil fuel consumption. As they argue, rising planetary temperatures could be an inevitable result of the exponential growth of energy consumption. Their findings could have serious implications for astrobiology and the Search for Extraterrestrial Intelligence (SETI).

The study was conducted by Amedeo Balbi, an Associate Professor of Astronomy and Astrophysics at the Universita di Roma Tor Vergata, and Manasvi Lingam, an Assistant Professor with the Department of Aerospace, Physics and Space Sciences and the Department of Chemistry and Chemical Engineering at the Florida Institute of Technology (Florida Tech). The paper detailing their findings, “Waste Heat and Habitability: Constraints from Technological Energy Consumption,” recently appeared online and is being reviewed for publication in the journal Astrobiology.

This chart shows the meteorological summer (June, July, and August) temperature anomalies each year since 1880. Credit: NASA’s Earth Observatory/Lauren Dauphin

The idea that civilizations will eventually overheat their planet harkens back to the work of Soviet scientist Mikhail I. Budyko. In 1969, he published a groundbreaking study titled “The effect of solar radiation variations on the climate of the Earth,” where he argued that “All the energy used by man is transformed into heat, the main portion of this energy being an additional source of heat as compared to the present radiation gain. Simple calculations show that with the present rate of growth of using energy the heat produced by man in less than two hundred years will be comparable with the energy coming from the Sun.”

This is a simple consequence of all energy production and consumption invariably producing waste heat. While this waste heat is only a marginal contribution to global warming compared to carbon emissions, long-term projections indicate that this could change. As Lingam related to Universe Today via email:

“The current contribution of waste heat to a rise in global temperature is minimal. However, if waste heat production proceeds on an exponential trajectory for the next century, a further 1 degree Celsius (1.8 F) rise in temperature may stem from waste heat, independent of an enhanced greenhouse effect because of fossil fuels. If the waste heat generation maintains its exponential growth over centuries, we show that it can eventually lead to a complete loss of habitability and the demise of all life on Earth.”

The Dyson Sphere is a fitting example of waste heat resulting from the exponential growth of an advanced civilization. In his original proposal paper, “Search for Artificial Stellar Sources of Infrared Radiation,” Freeman Dyson argued how the need for more habitable space and energy could eventually drive a civilization to create an “artificial biosphere which completely surrounds its parent star.” As he described, these megastructures would be detectable to infrared instruments due to the “large-scale conversion of starlight into far-infrared radiation,” meaning they would radiate waste heat to space.

“The heating we explore in our paper results from the conversion of any form of energy and is an unavoidable consequence of the laws of thermodynamics,” added Balbi, who was the study’s lead author. “For present-day Earth, this heating represents only a negligible fraction of the warming caused by the anthropogenic greenhouse effect. However, if global energy consumption continues to grow at its current rate, this effect could become significant within a few centuries, potentially impacting Earth’s habitability.”

To determine how long it would take for advanced civilizations to reach the point where they would render their home planet uninhabitable, Balbi and Lingam crafted theoretical models based on the Second Law of thermodynamics (as it applies to energy production). They then applied this to planetary habitability by considering the circumsolar habitable zone (CHZ) – i.e., the orbits where a planet would receive sufficient solar radiation to maintain liquid water on its surface.

“We adapted the calculation of the habitable zone, a standard tool in exoplanetary studies. Essentially, we incorporated an additional source of heating—stemming from technological activity—alongside the stellar irradiation,” said Balbi. Another key factor they considered is the exponential growth rates of civilizations and their energy consumption, as predicted by the Kardashev Scale. Using humanity as a template, we see that global energy consumption rates went from 5,653 terawatt-hours (TWh) to 183,230 TWh between 1800 and 2023.

This trend was not only exponential but accelerated over time, similar to population growth in the same period (1 billion in 1800 to 8 billion in 2023). Balbi and Lingam extrapolated this trend to measure the implications for habitability and determine the maximum lifespan of an advanced civilization once it has entered a period of exponential growth. Ultimately, they concluded that the maximum lifetime of technospheres is about 1000 years, provided that they experience an annual growth rate of about 1% throughout the period of interest.

Humanity’s energy consumption has experienced accelerated and exponential growth in the past two centuries. Credit: OurWorldInData.org/Energy Institute – Statistical Review of World Energy (2024)

These findings, said Balbi, have implications for humanity and in the Search for Extraterrestrial Intelligence (SETI):

“Our results indicate that the effect of waste heat could become substantial not only in Earth’s future but also in the development of any hypothetical technological species inhabiting planets around other stars. Consequently, considering this constraint could influence how we approach the search for technologically advanced life in the universe and how we interpret the outcomes of such searches. For instance, it may offer a partial explanation for the Fermi paradox.”

Balbi and Lingam also stress how these results present some possible recommendations for how we could avoid rendering our planet uninhabitable. Once again, there are implications for SETI since any solution we can envision is likely to have already been implemented by another advanced species. Said Balbi:

“Although our paper focuses on physics rather than solutions to societal challenges, we envision a few scenarios that could help a technological species mitigate the constraints of waste heating and delay its onset. A sufficiently advanced civilization might use technology to counteract heating, such as employing stellar shielding.”

“Alternatively, they could relocate much of their technological infrastructure off-world, moving into space. Such mega-engineering projects would have significant implications for our search for technosignatures. A less ambitious but perhaps more feasible approach would be to reduce energy consumption by slowing growth. Of course, we cannot predict which of these options is the most plausible.”

Further Reading: arXiv

The post Advanced Civilizations Will Overheat Their Planets Within 1,000 Years appeared first on Universe Today.

In late June, the Chang'e 6 lunar lander returned to Earth with samples of the moon. Now, the first paper about these samples has been published.

On Episode 129 of This Week In Space, Rod and Tariq talk with Pascal Lee about his Mars Simulation Base in the Arctic.

NASA is seeking the public's help for innovative solutions to help Artemis astronauts navigate in and around the lunar south pole.

Have you ever seen the Man in the Moon?

Scientists have found a group of faults near the moon's south pole that could pose seismic hazards for NASA's Artemis Program of lunar exploration that seeks to establish a presence in the region.

Black holes often appear in science fiction movies, largely because elements of their existence are still a mystery. They have fascinating impacts on the surrounding region of space too with distortions in space and time high on the list. A team of astronomers have found a supermassive black hole with twin jets blasting out an incredible 23 million light years, the longest yet. To put this into context, if you lined up 140 Milky Way galaxies side by side, then that’s the length of the jet! 

The presence of mass in the Universe distorts space-time in its vicinity and the more massive, the greater the distortion. Black holes are regions where gravity is so strong that nothing, not even light can escape. They form when a massive star runs out of fuel in the core and collapses under its own gravity. The process creates a point of infinite density known as a singularity. Surrounding the singularity at a distance that depends on the properties of the progenitor star, is the event horizon. If matter of any sort, even a passing spacecraft, gets dragged in through the event horizon then it is never able to escape. 

After the death of a massive, spinning star, a disk of material forms around the central black hole. As the material cools and falls into the black hole, new research suggests that detectable gravitational waves are created. Ore Gottlieb

One of the properties of a black hole are powerful jets, high speed streams of particles ejected from the regions around a black hole. The material ejected never quite reaches the event horizon but instead has been ejected from within the accretion disk. The magnetic fields of a black hole and the rotation of the disks of heated gas and dust can launch jets from the polar regions. They can travel at speeds near the speed of light and can shoot across thousands and millions of kilometres of space. The exact mechanisms of the jets are still not well understood. 

Astronomers observing with LOFAR (the Low Frequency Array) radio system spotted a jet so massive that its the equivalent of 140 Milky Way galaxies lined up side by side! For comparison the jet emanating from Centaurus A at the centre of our Galaxy spans about 10 Milky Way’s! It’s been nicknamed Porphyrion after the mythological giant in Greek culture. Dating back to a time when the universe was 6.3 billion years old, the jet has been found to be producing power equivalent to trillions of Suns!

The LOFAR ‘superterp’, part of the core of the extended telescope located in the Netherlands. Credit: LOFAR/ASTRON

The team that have studied the jet suggest that if giant jets like this were common in the early universe then they may well have been an influential force in the formation of galaxies. Modern jets seen in the nearby universe (and therefore at a later era in the evolution of the universe) seem to be much smaller by comparison. The conclusion is that perhaps the giant jets would have connected and fed energy and material to other nearby galaxies, driving their evolution. 

The survey undertaken by LOFAR revealed more than 10,000 of these megajets. Previous studies revealed only a few hundred large jets suggesting they were more rare but this latest research shows otherwise. It was a real labour of love though as the team searched radio images by eye, used machine-learning tools to scan the images and even enlisted citizen scientists around the world to help. Their paper was published in the Astronomy and Astrophysical journal. 

What of Porphyrion? The team followed up with observations with the Giant Metrewave Radio Telescope in Kitt Peak and the W. M. Keck Observatory in Hawaii to reveal the host galaxy 7.5 billion light years away. 

Source : Gargantuan Black Hole Jets Are Biggest Seen Yet

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