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Researchers probed the transit of cations across a nanopore membrane for the generation of osmotic energy. The team controlled the passage of cations across the membrane using a voltage applied to a gate electrode. This control allowed the cation-selective transport to be tuned from essentially zero to complete cation selectivity. The findings are expected to support the application of blue energy solutions for sustainable energy alternatives worldwide.

The eyes of raptors such as eagles can accurately perceive prey from kilometers away. Is it possible to model the camera technology after the bird's eyes? Researchers developed a new type of camera, which was inspired by the structures and functions of bird's eyes.

Team utilizes advanced statistical techniques to project the future groundwater depletion risk.

Lenses are used to bend and focus light. Normal lenses rely on their curved shape to achieve this effect, but physicists have made a flat lens of only three atoms thick which relies on quantum effects. This type of lens could be used in future augmented reality glasses.

Lenses are used to bend and focus light. Normal lenses rely on their curved shape to achieve this effect, but physicists have made a flat lens of only three atoms thick which relies on quantum effects. This type of lens could be used in future augmented reality glasses.

Growing concern about data theft and counterfeiting has inspired increasingly sophisticated security technologies, like hologram seals, that can help verify the authenticity of currency, passports and other important documents. However, as security technologies evolve, so do the techniques criminals use to get past them. To stay one step ahead of these bad actors, researchers report that they have developed a new photopatterning technique that creates two light-reactive images on one material.

A team recently developed an adhesive sensing device that seamlessly attaches to human skin to detect and monitor the wearer's health.

Landing on the far side of the moon is rarely attempted, due to difficulties communicating with Earth, but China is about to try. If successful, its Chang'e 6 mission will then bring lunar samples back home

A 2020 rule that slashed air pollution from ships may have boosted global temperatures sooner than thought, helping to explain why 2023 was so hot

I may have mentioned this case before, but it’s one that’s guaranteed to cause arguments, for it involves the Netherlands’ policy of allowing doctor-assisted suicide of patients with incurable and debilitating mental illness. The description is at the Free Press, and you can read about Zoraya ter Beck by clicking on the screenshot below:

The U.S, has no such policy, although the following states and countries have medical aid in dying for physical illnesses (see the Wikipedia article for notes and qualifications):

Physician-assisted suicide is legal in some countries, under certain circumstances, including Austria, Belgium, Canada, Luxembourg, the Netherlands, New Zealand, Portugal, Spain, Switzerland, parts of the United States (California, Colorado, Hawaii, Maine,Montana, New Jersey, New Mexico, Oregon, Vermont, Washington and Washington DC) and Australia (New South Wales, Queensland, South Australia,Tasmania, Victoria and Western Australia). The Constitutional Courts of Colombia, Germany and Italylegalized assisted suicide, but their governments have not legislated or regulated the practice yet.

I haven’t looked carefully at all these places to see if they allow physician-assisted suicide for the mentally ill, but as far as I know the Netherlands is unique in this respect. Canada was supposed to allow it, but has put it on hold.

Opposition to general euthanasia is often based on religion (“God will take you when it’s time”), and opposition to euthanasia for mental illness is based on the supposition that the illness may be temporary, so that people might recover and be glad they didn’t choose doctor-assisted suicide.

In my view, not only should people with any intractable illness that causes great pain should be allowed to die legally, and I don’t exempt mental illness. In fact, severe depression or bipolar disorder can be the equivalent of cancer: although mental illness might not kill you by itself, it can make life not worth living, so that death would seem to be an ethical choice for both the patient and the state. Further, at least in the Netherlands there are sufficient protections in place to ensure that a person who has a good chance of recovering will not be euthanized, and that the illness must be intractable as judged from previous medical interventions.

But I digress: click to read (it’s archived here):

The details:

Even as a child, Zoraya ter Beek had a persistent wish to die. Growing up in the quaint Dutch town of Oldenzaal, she never felt as if she fit in. At the age of 21, she was diagnosed with autism; a year later, she started wearing a “Do Not Resuscitate” tag around her neck. Last Wednesday, her wish was finally granted: after a three-year wait, Zoraya ended her life through physician-assisted suicide. She had just turned 29.

. . . .Zoraya received little or no support from her family. When she turned 18, she moved out of her childhood home to live with her boyfriend, Stein. He was ten years older than her, and her parents didn’t approve of the age difference. When I first contacted her, Zoraya had been estranged from her mother and three older sisters for six years. Her father died last year from cancer.

As a young adult, Zoraya felt unable to study, or embark on a career. She told me Stein, who is an IT programmer, was worried about how she felt, and encouraged her to get therapy. Over the course of a decade, she tried everything to relieve the symptoms of her mental illness—including, at last, 33 rounds of electroconvulsive therapy, where electric currents jolt the brain.

Zoraya’s last treatment was in August 2020, after which she says her psychiatrist told her: “There’s nothing more we can do for you. It’s never going to get any better.”

“After we heard that, we all kind of knew what that meant,” Zoraya told me, referring not only to herself but her boyfriend, her friends, and her doctors. “I was always very clear: if it doesn’t get better, I can’t do this.”

I ask you: who would insist that this young woman, in deep pain from mental illness that could not be cured or even helped, stay alive? And why?

And so Zoraya went ahead:

Earlier this month, she told The Guardian: “People think that when you’re mentally ill, you can’t think straight, which is insulting.”

“In the Netherlands,” she added, “we’ve had this law for more than 20 years. There are really strict rules, and it’s really safe.”

Zoraya had great faith in not only the law but also the medical profession.

“Doctors want to help people feel better,” she told me. “Doctors don’t become doctors to kill people, even if that’s what you’re wishing for.”

Nevertheless, Zoraya had a plan B—or, as she called it, an “escape plan”—in case her application didn’t get final approval. It was a suicide kit, which she told me she’d obtained from Exit International, an NGO that advocates for the legalization of voluntary euthanasia.

In the end, she didn’t need it. Zoraya had hoped to be euthanized on her birthday, May 2. But there had been some last-minute bureaucratic delays. Nevertheless, her assisted suicide was approved a couple of weeks ago.

Another argument against assisted suicide for the mentally ill is that it could lead to a “slippery slope,” in which people who aren’t that ill, or pretend that they’re suffering, use it as an exit when they could be cured. But although the number of cases of euthanasia for mental illness is increasing, I know the Netherlands’ criteria are sufficiently strict to halt any slope. The increasing numbers reflects, I think, the public’s increasing acceptance of euthanasia as a humane way to end a miserable life, as well as increasing dissemination of information:

The fact is an increasing number of people suffering from mental illness in the Netherlands are choosing to end their lives. Zoraya is right that the assisted dying law has been around for years, but even as recently as 2010, there were only two recorded cases of medically assisted suicide that involved psychiatric suffering. Last year, there were 138.

But Zoraya is all on board with the regulations as they are, and agrees that they should be strict. And so, with the help of a doctor, she ended her life:

Zoraya told me she didn’t want a funeral, because she didn’t think her friends would want to say goodbye. But she did want her boyfriend to be with her at the end. When I spoke to her, she described how she wanted to die:

I will take my place on the couch. [The doctor] will once again ask if I am sure, and she will start up the procedure and wish me a good journey. Or, in my case, a nice nap, because I hate it if people say, “Safe journey.” I’m not going anywhere.

On Wednesday, a friend of hers posted an announcement on X: “Zoraya passed away today at 1:25 p.m. Or as she saw it herself: she went to sleep.”

Few details of her death have been reported—except that her boyfriend was at her side.

It’s sad to envision this, but we are not at the point where conditions like Zoraya’s can be treated. But again, who can gainsay that she did what was best for her? Who could be so churlish as to say she must stay alive.

The answer: the faithful.

If you want to see religious jobs who argue that prayer and recognize the value of suffering should have kept her alive, read this article in the Catholic Herald: “Zoraya ter Beek deserved doctors who cherished her life as precious.”  A quote from that:

As Catholics, we have a powerful message to tell that there is value to be found in suffering: when we step into church, we are met with the sight of Christ crucified, and are reminded of the agony he bore because he loved us. In fact, it’s because Christ experienced being human that we can be sure that he understands and cares for us in our suffering. Still, most of us are not lawmakers. We’re not campaigners or politicians. Trying to justify our Catholic beliefs to the world can seem overwhelming – almost pointless, when our faith is so often denigrated.

As Catholics, we must continue to remind ourselves of the power of prayer; not exclusively praying for a change of heart of those in positions of power who may choose to legalise assisted dying, though that is of course important, but rather praying in order to cultivate closeness to God in our own lives. We must rely on God first, and only then can we show others that we can help them bear their pain. We must confide in the one who bore the greatest pain for us, and petition, in prayer, to be given the strength to imitate his goodness and his compassion in our own lives. Finally, we must never lose hope, even in cases where a person appears determined to die. We must pray for them to the very end, for by God’s grace, no soul is ever truly beyond saving.

This is the maliciousness of religion: keep the suffering going, for superstition tells us that God will make it all right in the end.  It’s horrible.

Here she is in a video made by The Free Press:

Humans from many cultures tend to associate the nonsense words “bouba” and “kiki” with different shapes – and now it seems that 3-day-old chicks have the same inclinations

Astronomy is a profession that, so far, has only been done at night, at least on Earth. Light from the Sun overwhelms any light from other stars, making it impractical for both professional and amateur astronomers to look at the stars during daytime. There are several disadvantages to this, not the least of which is that many potentially exciting parts of the sky aren’t visible at all for large chunks of the year as they pass too close to the Sun. To solve this, a team from Macquarie University, led by graduate student Sarah Caddy, developed a multi-camera system for a local telescope that allows them to observe during daytime.

The University has a system known as the Huntsman Telescope, named after the famous Australian spider species. Its design was inspired by the Dragonfly Telescope Array, initially designed by researchers at the University of Toronto and Yale, among other institutions. Both telescopes feature an array of 10 telephoto lenses from Canon, the camera manufacturer, arranged in a honeycomb pattern.

Typically, the telescope is used for nighttime astronomy at the Siding Spring Observatory, about a seven-hour drive from Sydney. However, Ms. Caddy thought it could do better and potentially continue observations during the day.

An image of Betelgeuse during the day using the Huntsman Telescope.
Credit – Macquarie University

They originally tested their ideas, which focused on a number of broadband filters and a single-lens test version of the Huntsman telescope. This allowed them to optimize things like exposure times and timing and show a proof of concept that they then wrote up in a paper in the Publications of the Astronomical Society of Australia. 

In particular, Ms. Caddy and her colleagues are excited about several use cases. One is tracking particular stars that might soon undergo an exciting event. Betelgeuse comes to mind, as astronomers expect it to undergo a supernova sometime “soon,” though soon in astronomical terms could mean anywhere between tomorrow and 10 million years from now. If Betelgeuse happens to be on the other side of the Sun when it goes supernova, without daylight astronomy, there would be months of a gap where we would miss out on collecting data on the supernova that happened nearest to us in recorded history, and astronomers everywhere would be frustrated.

This is exactly why the Huntsman team used a daytime image of Betelgeuse as part of their proof of concept. While it might not look like a typical image of the star that is 650 light years away, the fact that it is visible at all during the daytime is striking.

Betelgeuse is one of the most interesting stars in the sky – a potential supernova that goes through occasional dimming periods, as Fraser explains.

Another use case is the tracking of satellites. As the orbital space around Earth becomes increasingly crowded, there’s a higher likelihood that satellites will begin colliding, which could eventually result in something as severe as Kessler syndrome, which we’ve discussed before here at UT. Unfortunately, astronomers can only track satellites during the night, so if one of their orbits happens to shift for some reason during a day cycle, it would be impossible for them to suggest changes to the orbital paths of other satellites that are close by.

Unless you have daytime astronomy, which allows you to track satellites during the day, there’s a significantly decreased risk of two running into each other unexpectedly. This data can be combined with radar readings to help avoid catastrophic collisions, no matter how crowded orbital space gets.

This proof of concept is a step toward making those observations a reality. As it is more fully tested, the southern sky will become much more accessible, and it could pave the way for other daytime astronomy projects in other parts of the world.

Learn More:
Macquarie University – Stargazing in broad daylight: How a multi-lens telescope is changing astronomy
Caddy, Spitler & Ellis – An Optical Daytime Astronomy Pathfinder for the Huntsman Telescope
UT – Astro-Challenge: Adventures in Daytime Astronomy
UT – Why Can We See the Moon During the Day?

Lead Image:
Macquarie’s Huntsman Telescope can potentially observe space during the day.
Credit – Macquarie University

The post A New Telescope Can Observe Even in Broad Daylight appeared first on Universe Today.

We asked New Scientist staff to pick their favourite science fiction books. Here are the results, ranging from 19th-century classics to modern day offerings, and from Octavia E. Butler to Iain M. Banks

One of the things that worried me about the protestors (i.e., the encampers), most of whom were affiliated with the consortium UChicago United for Palestine (UCUP, one of whose subgroups is the Students for Justice in Palestine), is that they will attempt to disrupt graduation on Saturday by making noise, chanting, and generally creating a ruckus with their pro-Palestinian vigor. These were, after all, the people who were largely behind the Encampment, and their main function seems to be disrupting campus activities. Even though they’ve gained nothing I can see from all legal or illegal demonstrations, and in fact have angered a lot of people with their performative activism, they’ve vowed to keep on keeping on, and that includes disrupting graduation. (The Encampment didn’t make the administration yield to any of the protestors’ demands.)

As The Chicago Tribune reported yesterday, the University of Chicago is withholding the degrees of four students who participated in the encampment, all pending resolution of formal disciplinary hearings about their participation. This doesn’t mean they won’t graduate if the hearings exculpate them, but if they’re found guilty they don’t get their degrees. As the Tribune said:

A U. of C. spokesman said the school could not comment on individual student disciplinary matters, but noted that the process is standard practice after a formal complaint is reviewed by the university’s Disciplinary Committee.

“The recent protests on campus brought about multiple formal complaints alleging that students violated University policies, including by engaging in disruptive conduct,” the university said. “Once a formal complaint is received and, if the Disciplinary Committee faculty lead concurs that the complaint is credible, the matter may be referred to the Standing Disciplinary Committee on Disruptive Conduct to determine if policies have been violated.”

The four students are still able to participate in graduation and other end-of-year events, and their degrees can be later conferred depending on the resolution of the disciplinary process. But if the committee finds that certain policies have been violated, their degrees could be denied, despite four years of coursework and tuition.

Undergraduate tuition for the prestigious institution exceeds $67,000, and rises to more than $93,000 after including housing, food and other miscellaneous expenses.

The four students under investigation (the article implies there are others as well), along with many in the community in general, are furious that any such punishments are being levied on those who violated University rules. (The old notion of taking your punishment for civil disobedience seems to have vanished.)

My own view, which I’ve expressed here often, is that punishments for the guilty are needed if we’re going to tamp down the degree of illegal disruption on campus. So far the University doesn’t seem to have had much stomach for punishment, but that, of course, will only guarantee that disruption of campus life will continue.  The war in Gaza is going to last a while, and it’s easy to see that unless there are sanctions on the table, illegal disruptions could continue for several years. (I’m not, of course, opposed to pro-Palestinian demonstrations so long as they don’t violate the “time, place, and manner” rules of the University. Legal demonstrations are a manifestation of the free speech for which the University of Chicago is famous.)

Unfortunately, UCUP is not only threatening to disrupt graduation (an illegal activity), but is making concrete plans to do so. Have a gander at these two posts from the UCUP Instagram page (each screenshot links to the post):

Note: “Be sure to bring drums and noise makers as we rally for Rafah.” You know what that means: a lot of shouting, chanting, and banging during a ceremony that is really important to many graduates.

You might expect that UCUP would let these graduates enjoy the formal termination of their studies here, but you would expect wrongly. UCUP wants to disrupt, and are apparently heedless that they would lose sympathy from the community if they screw up graduation.  But changing minds is not, I think, their main aim.

Here’s another screenshot.

Rally at 10 AM on Saturday, with the location to be arranged (it’ll be given out on private chatrooms). Since the convocation (the ceremony) is scheduled to start at 9:15 a.m., this will be right when the ceremony is under way. I’ll be around to report what happens.

When the Arecibo Observatory dish in Puerto Rico collapsed in 2020, astronomers lost a powerful radio telescope and a unique radar instrument to map the surfaces of asteroids and other planetary bodies. Fortunately, a new, next-generation radar system called ngRADAR is under development, to eventually be installed at the 100-meter (328 ft.) Green Bank Telescope (GBT) in West Virginia. It will be able to track and map asteroids, with the ability to observe 85% of the celestial sphere. It will also be able to study comets, moons and planets in our Solar System.

“Right now, there is only one facility that can conduct planetary radar, the 70-meter (230-foot) Goldstone antenna that is part of NASA’s Deep Space network,” said Patrick Taylor, the project director for ngRADAR and the radar division head for the National Radio Astronomy Observatory. “We had begun this process of developing a next generation radar system several years ago, but with the loss of Arecibo, this becomes even more important.”

The iconic Arecibo Radio Telescope, before its collapse in 2020: Credit: UCF

Planetary radar can reveal incredibly detailed information about the surfaces and makeup of asteroids, comets, planets, and moons. The ngRADAR system could provide unprecedented data on these objects. In fact, a recent test with a low-power prototype of ngRADAR at the GBT produced some of the highest resolution planetary radar images ever captured from Earth. But the hallmark of the new system will be seeking out near Earth asteroids and comets to evaluate any hazard they might present to our planet. 

“Radar is really powerful in determining the orbits of these asteroids and comets,” Taylor told Universe Today in an interview, “and the new system will deliver very precise data that will allow us to predict where these small bodies will be in the future. That will be one of the highest priority uses for the next generation radar system, where we can track and characterize near-Earth asteroids and comets to evaluate any hazard they might present to Earth in the future.”

A Radar Flashlight

Usually, radio telescopes collect weak light in the form of radio waves from distant stars, galaxies, and other energetic astronomical objects – including black holes or cold, dark objects that emit no visible light. While radio telescopes don’t take pictures in the same way visible-light telescopes do, the radio signals detected are amplified and converted into data that can be analyzed and used to create images. 

But radio telescopes can also be used to transmit and reflect radio light off planetary bodies in our Solar System. This is called planetary radar or Solar System radar.

This collage shows six planetary radar observations of 2011 AG5 a day after the asteroid made its close approach to Earth on Feb. 3, 2023. With dimensions comparable to the Empire State Building, 2011 AG5 is one of the most elongated asteroids to be observed by planetary radar to date. Credit: NASA/JPL-Caltech

What is planetary radar and how does it work?

“Essentially we have a flashlight that works in radio waves,” Taylor explained. “Our narrow flashlight beam does not look at the whole sky, but we point it in a very precise location – the surface of an asteroid or moon. We know very well what our flashlight’s properties are, so we know exactly what we send out. When we receive the echo back from wherever we pointed our flashlight, we analyze that signal and see how it changed compared to what we transmitted.”

That’s what makes planetary radar so powerful and different from any other type of astronomy.  

“When astronomers are studying light that is being made by a star, or galaxy, they’re trying to figure out its properties,” Taylor said. “But with radar, we already know what the properties of the signals are, and we leverage that to figure out the properties of whatever we bounced the signals off of. That allows us to characterize planetary bodies – like their shape, speed, and trajectory. That’s especially important for hazardous objects that might stray too close to Earth.”

In the past, planetary radar has been used to image asteroids, but also precisely measure the position and motion of the planets, allowing us to land spacecraft on Mars and to explore the outer Solar System. The technique has also made surprising discoveries, such as the finding the presence of water ice on Mercury.  

The 70m telescope at the Goldstone Deep Space Communications Complex in California’s Mojave Desert. (NASA/JPL)

Because radio waves are much longer than visible light waves, radio astronomy requires large antennas. The 70-meter Goldstone antenna located in California’s Mojave Desert, is primarily used to communicate with spacecraft as part of NASA’s Deep Space network. But it is also frequently used for planetary radar to study near Earth asteroids, and — as previously mentioned — is the only facility currently available to perform planetary radar. Previously, the workhorse for planetary radar was the 1,000-foot-diameter (305 meters) Arecibo Observatory, which was about 20 times more sensitive and could detect asteroids about twice as far away than Goldstone.

However, because Arecibo’s dish was stationary and built inside a round sinkhole, it was fixed to the Earth and could only view whatever part of the sky happened to be straight overhead. That meant Arecibo’s dish could only see about one-third of the sky. Goldstone is fully steerable, can see about 80 percent of the sky, can track objects several times longer per day, and can image asteroids at finer spatial resolution.

ngRADAR

The Robert C. Byrd Green Bank Telescope is the world’s largest fully steerable radio telescope. The maneuverability of its large 100-meter dish allows it to quickly track objects across its field of view, and see 85% of the sky.

The GBT’s new radar system will introduce a high-resolution tool that will be a vast upgrade, collecting data at higher resolutions and at wavelengths not previously available. Scientists at GBT and the National Radio Astronomy Observatory (NRAO) are also developing advanced data reduction and analysis tools that have not been available before, providing astronomers with unprecedented planetary radar capabilities.

To test out the proof of concept, Taylor and his team worked with the company Raytheon — a long-time developer of radar systems for both the military and science applications, and specifically the Raytheon Intelligence & Space (RIS)division — to build a small version of the transmitter, with a lot less power.

“Our friends at Raytheon built a transmitter that could output 700 watts, so about half the power of a microwave oven,” Taylor said. “Ultimately, we want to build a system with 500 kilowatts, so up by a factor of a thousand. But even with 700 watts, we were able to do some really impressive observations.”

Radar image of the Apollo 15 landing site. Credit: Raytheon/NRAO.

GBT’s planetary radar was aimed at the Moon, specifically at the Apollo 15 landing site in Hadley Rille, and at the giant Tycho Crater. ’s surface, and radar echoes were received with NRAO’s ten 25-meter VLBA antennas. At Tycho, the crater was captured with 5-meter resolution, showing unprecedented detail of the Moon’s surface from Earth. Taylor said the resolution with the ngRADAR prototype approached the optical resolution on Lunar Reconnaissance Orbiter, taking images with its high-resolution cameras from orbit around the Moon.

“The images of the crater floor were actually breathtaking,” Taylor said. “It’s pretty amazing what we’ve been able to capture so far, using less power than a common household appliance.”

A Synthetic Aperture Radar image of the Moon’s Tycho Crater, showing 5-meter resolution detail. Image credit Raytheon.

Additionally, the prototype radar also detected a potentially hazardous asteroid named (231937) 2001 FO32, which happened to be flying past Earth at about six times more distant than the Moon during their radar pings. The asteroid is considered potentially hazardous because of its size, approximately 1 kilometer in diameter, along with how close it can get to Earth, at just over 2 million kilometers away. The asteroid’s detection appeared as a spike in their data.

“Just from the spike in our data, we can now figure out how fast this object is moving, determine its orbit, and figure out its trajectory in the future,” Taylor explained. “We can determine its impact risk and assess how much of a hazard it is, and even constrain its spin state, its size, its composition, its scattering properties, and so on. So, even though the data spike doesn’t look like much, that one little detection can tell you a lot of information about the asteroid.”

Radar signals transmitted by the GBT will reflect off astronomical objects, and those reflected signals will be received by the Very Long Baseline Array (VLBA), a network of ten observing stations located across the United States.

“The idea is for GBT is to do the transmitting almost constantly and the VLBA — either all ten of those or any subset of those telescopes — doing the receiving,” Taylor said. “This new system will allow us to characterize the surfaces of many different objects in a different frequency or wavelength that hasn’t been used before.”

Next: Part 2 of this series will look at the details of ngRADAR, the history of planetary radar, and take you up close to the GBT.

The post Next-Generation Radar Will Map Threatening Asteroids appeared first on Universe Today.

We are rapidly entering the era of neuromodulation – using electrical and magnetic fields in order to increase or decrease the activity of specific regions and circuits in the brain. Such treatments are already shown to be effective in treating some Parkinson’s symptoms, depression, OCD, migraines, and other neurological and psychiatric conditions. Computational models of brain anatomy and the connectome have dramatically increased the utility of neuromodulation. We are still on the steep part of the curve, and it will be interesting to see how far this modality goes in the next 10-20 years.

But there is one technical challenge – reaching the deep brain structures where many of the potentially targeted conditions can be found. The problem is that any electrical or magnetic field has to go through the more superficial brain tissue to get to the deeper structures. The current solution to this problem is to use invasive techniques, such as placing wires in the brain. So called “deep brain stimulation” is now done routinely, using guided stereotactic techniques, but a non-invasive way to accomplish the same goal could lead to a dramatic increase in the utility of neuromodulation.

Researchers have now published a proof of concept study looking at what they call transcranial temporal interference stimulation (tTIS).  The idea of tTIS is actually rather simple – it exploits the phenomenon of interference. Waves, regardless of what kind of waves they are, display certain core behaviors, one of which is interference. Wave are basically additive. If a peak hits a peak you get a bigger peak. If the peak of one wave coincides with the trough of another wave, the two waves will cancel each other out. This is how noise cancelling headphones work, for example.

Brain activity has a rather low frequency, and hence responds to low frequency modulation. Much higher frequencies will not coincide with brain waves and therefore have little net effect on brain activity. With tTIS, therefore, you can use two electrical stimulations that are both high frequency but off by a small amount. In the current study they used one frequency of 2000 hz and one of 2080 hz. These are both too high to directly affect brain function, so they can pass through brain tissue harmlessly. You can then aim these beams so that they intersect on the desired deep brain tissue. There the 2000 hz will essentially be subtracted from the 2080 hz, leaving an 80 hz electrical frequency. And that is a frequency which does cause neuromodulation. Voila – non-invasive deep brain stimulation.

In the study they stimulated the striatum of 24 healthy human subjects during reinforcement learning tasks. They found that at 80 hz the tTIS interfered with reinforcement motor learning, while at 20 hz (or sh am stimulation) there was no effect. The subjects had to use the force of their grip on a hand-grip force sensor to control a cursor track a moving object. The hypothesis is that the activity of the striatum is causative of improvement in the task performance through reinforcement motor learning. They found that at 80 hz the subjects did not improve with motor learning, while at 20 hz or sham stimulation they did.

This brings up a nice feature of tTIS as a research tool (and other forms of neuromodulation). These studies are really easy to double blind. The subject has no idea what frequency of electrical stimulation they are receiving. This is now even more true for tTIS, because the effect comes from the small difference between two electrical frequencies – imperceptible to the subject.

It’s also a good example of the power of different technologies working in tandem. Here we use functional MRI scanning to see what’s happening in the brain, tTIS to modulate brain activity, and computers to model what is happening and which parts of the brain are doing what. Increasingly this computer modeling is incorporating AI to help make sense of lots of noisy data. The result is a dramatic increase in the pace of the kinds of research that can benefit from such technologies.

Think about how useful this is for neuroscience research. I wonder what that part of the brain does. Well, let’s turn it off or stimulate it and find out. The goal is to achieve not just a map of the brain or a map of all the connections in the brain, but a functional map of the brain – what are all the modules and circuits and what do they do? How does their function work as part of the whole, and what effect do they have on other circuits in the brain. This research will still take a long time, because the brain is horrifically complex, and there is a lot of neurodiversity out there. But the pace is accelerating.

Then, with this information we can make computer models to test how our models of the brain work, and to further test our hypotheses. Eventually, perhaps, the end result of all this research will be a complete computer model of a human brain. The question is – as I have speculated before – will this computer model of the human brain be, essentially, a human brain? Will it be capable of consciousness? I see no reason why not, as long as it is functioning. In fact, this is one pathway to achieving general AI, just modeling the human brain.

Imagine how useful this computer model will be to research. We would then have unlimited power to adjust the functional parameters of every aspect of brain function to see the effect this has on the whole. But then, if the computer model can be reasonably argued to be conscious, we would run into ethical considerations. Would we need consent from the computer model to mess with its function? Would that consent be free? What if we just keep making copies of the computer model with small tweaks until we get one that consents? What if we name it “Colossus” and put it in charge of our nuclear launch codes? It will be interesting times.

The post Non-Invasive Deep Brain Stimulation first appeared on NeuroLogica Blog.

A star in a distant galaxy appears to have been almost torn apart in a close shave with a supermassive black hole, not once but twice – and astronomers hope to see it happen again

Studying gas in the Universe is no easy task. We often look to ‘non-visible’ wavelengths of the electromagnetic spectrum such as X-rays. The Chandra X-Ray observatory has been observing a vent of hot gas blowing away from the centre of the Milky Way. Located about 26,000 light years away, the jet extends for hundreds of light years and is perpendicular to the disk of the Galaxy. It is now thought the gas has been forced away from the centre of the Milky Way because of a collision with cooler gas lying in its path and creating shockwaves. 

The Chandra X-ray observatory was launched by NASA in 1999. Since then, it has been orbiting above the atmosphere, probing space in high energy X-rays. It provides us with stunning, high resolution data that allows us to study black holes, supernova remnants and other high energy events in unprecedented detail. 

Artist’s illustration of Chandra

Using the power of the Chandra telescope to study the centre of our Galaxy, ridges that were perpendicular to the plane of the Milky Way were seen at a distance of 26,000 light years. The team of researchers believe the ridges are the walls of a tunnel that is shaped like a cylinder. The structure helps to funnel hot gas along, much as a chimney does over a fireplace, and away from the centre of the Galaxy. The vent is about 700 light years long and extends away from the core of the Milky Way. 

The structure was previously spotted using earlier data from Chandra but also from the XMM-Newton project too. The radio emission have been detected by the MeerKAT radio array ( based in South Africa this array is made up of 64 receivers ) too and shows the powerful effects of magnetic fields channeling gas along the chimney. Lead scientist Scott Mackey from the University of Chicago said “We suspected that magnetic fields are acting as the walls of the chimney and that hot gas is travelling up through them, like smoke.” He continued “Now we’ve discovered an exhaust vent near the top of the chimney.”

Exploring the Chandra data, the team think the vent formed from a collision as hot rising gas through the tunnel collided with cooler gas. The bright ridges in the walls are thought to be the result of shock waves generated by the collision. The left portion of the tunnel seems brighter because the gas flowing upwards has struck the chimney at a more direct angle and imparted more energy. 

As for the origins of the hot gas, it is thought this is coming from material falling into the black hole at the centre of the Galaxy. As material accretes around the black hole, a series of events can cause material to be ejected from the accretion disk, forcing the gas along the chimney.  X-ray flares are thought to take place every couple of hundred years near the black hole where blasts of X-ray radiation reflects off a build up of hot plasma. These flares are thought to drive the hot gas upwards and out through the vent. 

The diagonal line of bright objects in this image of the heart of our Milky Way Galaxy are all powerful sources of radio waves. The bright center is the home of the supermassive black hole, Sagittarius A*. The dense, bright circles are the nurseries of new, hot stars and the bubbles are the graveyards of exploded, massive stars. The thread-like shapes are not yet understood, but probably trace powerful magnetic field lines. This giant image was assembled from observations made by the Very Large Array (VLA).

One of the outstanding questions requiring extra research is the ultimate driving force behind the energy release. Is it a one off major event like the death of a star as it is ripped apart by the black hole or a series of smaller events that build up? Further studies are needed to fully understand the events at the centre of the Galaxy and to build a fuller picture of the nature of the vent at the centre of the Galaxy. 

Source : NASA’s Chandra Notices the Galactic Center is Venting

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As humanity returns to the Moon in the next few years, they’re going to need water to survive. While resupplies from Earth would work for a time, eventually the lunar base would have to become self-sustaining? So, how much water would be required to make this happen? This is what a recently submitted study hopes to address as a team of researchers from Baylor University explored water management scenarios for a self-sustaining moonbase, including the appropriate location of the base and how the water would be extracted and treated for safe consumption using appropriate personnel.

Here, Universe Today discusses this research with Dr. Jeffrey Lee, who is an assistant adjunct professor in the Center for Astrophysics, Space Physics & Engineering Research at Baylor University, and lead author of the study, regarding the motivation behind the study, significant results, the importance of having a self-sustaining moonbase, and what implications this study could have for the upcoming Artemis missions. Therefore, what is the motivation behind this study?

Dr. Lee tells Universe Today, “This paper is actually an eclectic diversion for me from my astrophysics research on primordial black holes, early universe cosmology, breakthrough propulsion physics, and my geophysics research on asteroid impacts. If human missions throughout the Solar System, particularly to Mars, are to be realized, then a permanent lunar facility seems to be a logical early step.”

For the study, the researchers investigated water management requirements for a 100-person self-sustaining lunar base measured at 500 m x 100 x 6 m (1640 ft x 328 ft x 20 ft), including the location of the lunar base near water ice deposits, the technology required to convert the water ice to water vapor (since liquid water can’t exist on the Moon), and the technology required for water treatment and recovery that would result in safe consumption for the 100-person base. The study used the current water usage estimates for American households, which is approximately 100 gallons per day (GPD) per person, which includes cleaning, cooking, drinking, flushing toilets, and washing clothes.

Additionally, the researchers examined the amount of water required for agricultural, technical, and overall needs for the lunar base. Regarding the location of the lunar base, the researchers deduced that the best location for the base would be either near, or exactly on, the Shackleton-de Gerlache Ridge, which is located at 89.9°S 0.0°E, or almost directly on the lunar south pole. The reason this location is ideal for water ice deposits is because Shackleton Crater resides within a permanently shadowed region (PSR), meaning it is shrouded in permanent darkness due to the Moon’s small axial tilt, and water ice has potentially built up over billions of years.

In the end, the team concluded the water requirements for the 100-person lunar base for human, agricultural, and technical needs are 12.3, 72, and 2 acre-feet per year. For context, one acre-foot is equivalent to approximately 326,000 gallons, so a 100-person lunar base would need more than 4,000,000 gallons per year for human needs, more than 23,000,000 gallons per year for agricultural needs, and 652,000 gallons per year for technical needs. So, based on these findings, what were the most significant results from this study, and what follow-up studies are currently in the works or being planned?

Dr. Lee tells Universe Today, “There is good evidence that sufficient water exists on the Moon to support a permanent lunar colony, and the acquisition, treatment, and distribution of the lunar water can be achieved with current technology. An appropriate administrative structure will be necessary to oversee all aspects of lunar water. The relative scarcity and management of water on the Moon can potentially provide insight for improving the management of water on Earth. The next study for my group will be to investigate the ways in which the management of lunar water could help to improve terrestrial water management. However, the timeline for this research is yet to be determined.”

The study discusses in-situ resource utilization (ISRU), which is using available, on-site resources for both sustainability and survivability. In this case, using water ice deposits on the Moon, and specifically near the south pole of the Moon, to meet the water needs of a 100-person, self-sustaining lunar base. The potential for NASA using ISRU has gained considerable traction in the last few years since sending water from the Earth to the Moon could prove to be extremely costly. But aside from the financial risks, if a resupply mission gets delayed or fails on the way to the Moon, the crew could face significant danger. Therefore, learning to “live off the land” for a lunar base could prove to be a viable, long-term option for mitigating the need of resupply missions from Earth. But what additional importance could a self-sustaining moonbase also provide?

Dr. Lee tells Universe Today, “Over the years, there has been a groundswell of excitement at the prospect of colonizing Mars. Indeed, at present, we are conceivably able to mount a short-term human voyage to the Red Planet in which the astronauts would collect samples, conduct experiments, plant flags, and when the next launch window occurs, return to Earth. However, the permanent colonization of Mars is much more ambitious and challenging. Mars is much farther away than the Moon, requiring 9 months to get there and a round trip time of 21 months (a 3-month stay on Mars is needed until the next launch window arrives).”

NASA’s goal is to send humans to Mars through the agency’s Moon to Mars Architecture, which is an elaborate, years-long endeavor to develop the necessary technologies on the Moon for use during a crewed mission to the Red Planet. This includes science, infrastructure, transportation, habitation, and operations, just to name a few. However, as noted, while we can (possibly) send humans to the Red Planet for short-term stays with our current technology, a long-term human presence on Mars would require significantly more time and resources.  

Dr. Lee tells Universe Today, “Beyond low Earth orbit, the Moon is a logical next destination. Lunar colonization is technologically achievable, and in comparison to Martian colonization, it is far easier. Being capable of establishing a moonbase seems like an obvious prerequisite for establishing a Mars base. Furthermore, the Moon would be an excellent jumping off point for further Solar System colonization including potentially the eventual establishment of small colonies in the interiors of Near-Earth Asteroids. Additionally, some have suggested that the Moon is an ideal location from which the interception of Earth-bound asteroids could be conducted.”

This study comes as NASA’s Artemis program plans to land the first woman and person of color on the lunar surface in the next few years. The current landing sites of the Artemis missions are near the south pole to access nearby water ice deposits within the aforementioned PSRs and could be ideal to develop ISRU technologies that can also be used on future Mars crewed missions, as well. Therefore, what implications could this study have for the upcoming Artemis missions?

“Short term lunar visits, such as the planned Artemis missions would not require lunar water,” Dr. Lee tells Universe Today. “In these instances, sufficient water could be brought from Earth. However, if at some point in the future, a lunar colony were to become a priority, future Artemis missions could serve to provide valuable in situ information about the presence and abundance of lunar water, particularly at the lunar south pole and in proximity to the Shackleton Crater (an ideal area for a moonbase).”

How will water management play a role in a self-sustaining lunar base in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post How Much Water Would a Self-Sustaining Moonbase Need? appeared first on Universe Today.

Over the last few months, Universe Today has explored a plethora of scientific fields, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, and organic chemistry, and how these various disciplines help scientists and the public better understand our place in the cosmos.

Here, we will discuss the fascinating and mysterious field of black holes with Dr. Gaurav Khanna, who is a Professor in the Department of Physics at the University of Rhode Island, regarding the importance of studying black holes, the benefits and challenges, exciting aspects of studying black holes, and how upcoming students with to pursue studying black holes. So, what is the importance of studying black holes?

“Gravity is the oldest known, but the least understood force in nature,” Dr. Khanna tells Universe Today. “For students of gravity, black holes are amongst the most interesting objects to study because gravity is the dominant force there — in fact, it is infinitely strong! Then there are astrophysical reasons of interest in black holes. They play important roles in galaxies, perhaps even in the large-scale behavior of the universe and more. The other thing to note about black holes is that they are very ‘simple’ especially when compared to stars and other astrophysical objects. This is a consequence of the so-called ‘no hair’ theorem that states that black holes can be fully characterized by only 3 attributes — their mass, charge and spin. That simplicity makes them particularly appealing to study and research.”

Black holes are known for exhibiting gravity so strong that light can’t even escape, and while Albert Einstein’s theory of general relativity in 1915 is often credited with first proposing the concept of black holes, the concept of an object whose size and gravity would not allow light to escape was first proposed in a November 1784 letter by English philosopher and clergyman, John Mitchell. In this letter, Mitchell referred to these objects as “dark stars” since he postulated that stars whose diameters exceeded 500 times that of our Sun’s diameter would trigger the formation of these objects. Additionally, he suggested that gravitational waves influencing nearby celestial bodies would enable these objects to be detected.

Fast forward to Einstein’s theory of general relativity, which also predicted both the existence of black holes and gravitational waves, both of which continued to be scrutinized throughout the 20th century, which includes what’s called the “golden age of general relativity” during the 1960s and 1970s. This includes the first object accepted by the scientific community as a black hole, called Cygnus X-1, which was discovered in 1964. However, it took another 52 years for the existence of gravitational waves to be confirmed through a black hole merger, which was accomplished by the LIGO Scientific Collaboration. Therefore, given the extensive history combined with key discoveries only occurring within the last few years, what are some of the benefits and challenges of studying black holes?

Dr. Khanna tells Universe Today, “As I stated above, studying black holes, which are a consequence of Einstein’s relativity theory, offers insight on the nature of gravity, space and time at the most fundamental levels. As physicists, we are yet to develop a complete understanding of the quantum nature of gravity, and black holes are the key to unlocking that mystery. On the challenges, I’d say that the clearest one perhaps is that black holes can only be observed indirectly. Unlike stars, since they don’t emit radiation themselves, it is difficult for astronomers to collect data on them. At best, we can observe their influence on their environment (like gas, stars, etc.) and infer their properties and behavior. On the theoretical side, while it is indeed true that black holes are very “simple” compared to stars, there are still challenges. The mathematics and physics that describe them is fairly advanced and even computer simulations involving them are challenging requiring massive processing power and memory.”

While it took over 100 years between Einstein introducing his theory of general relativity in 1915 and the confirmation of gravitational waves in 2016, it only took another three years for astronomers to publish the first direct image of a black hole at the center of the Messier 87 galaxy. The results were published in The Astrophysical Journal Letters and based on observations taken in 2017 by the powerful Event Horizon Telescope (EHT). While Messier 87 is located approximately 53 million light-years from Earth, the closest hypothesized black hole, Gaia BH1, is located approximately 1,560 light-years from Earth. In 2022, astronomers published a direct image of Sagittarius A*, which is the supermassive black hole at the center of our Milky Way Galaxy.

Additionally, scientists hypothesize the number of black holes in our Milky Way Galaxy is in the hundreds of millions, despite only a few dozen known black holes having been confirmed, thus far. But what are the most exciting aspects about black holes that Dr. Khanna has studied during his career?

Dr. Khanna tells Universe Today, “I suppose I’d probably refer to my recent work on how very rapidly rotating black holes attempt to ‘grow hair’ but ultimately fail. The project is interesting because it appears to suggest a violation of the ‘no hair’ theorem that I mentioned earlier, but it ultimately doesn’t. So, it is provocative, but then relieving! More importantly, we are now using the main context of that research to develop a new observational ‘signature’ or test for rapidly rotating black holes, a.k.a. near-extremal black holes. Such black holes have several peculiar properties and aspects and are an area of active research.”

Black holes are studied by astronomers, physicists, and astrophysicists, who use a combination of theory and observations to construct what black holes might look like, and in rare cases, as discussed, obtain direct images of them. Regarding theory, researchers use mathematical calculations and computer models to simulate what black holes might look like, and then have used powerful ground-based telescopes like EHT to obtain the few direct images of black holes. It is important to note that these direct images don’t capture the black hole itself, but the gases that are encircling the black hole’s event horizon, or the unofficial boundary where light can’t escape the black hole. But what advice can Dr. Khanna offer upcoming students who wish to pursue studying black holes?

Dr. Khanna tells Universe Today, “I would offer them a lot of encouragement! There is a lot to do in this space and many mysteries to solve. New observations are going to open many new doors and brand-new avenues for research. This is amongst the best times to be a black hole astrophysicist!”

Dr. Khanna continues, “The one thing that I could say perhaps that isn’t as much emphasized elsewhere is about computing as a tool to study black holes. Mostly there is heavy emphasis on learning advanced mathematics as the background for serious research in black holes — and for good reason — that continues to be critical for every student of Einstein’s relativity theory which is the foundation for black hole physics.  In recent years, computer simulations have advanced rapidly, and one can now make major discoveries about deep questions using computational tools. In the long run, computer programming would be a very promising tool for advancing research in this field and many others as well.”

How will black holes help us better understand our place in the universe in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Black Holes: Why study them? What makes them so fascinating? appeared first on Universe Today.