Category: The Conversation

Source: The Conversation – USA – By Keri K. Stephens, Professor & Co-Director, Technology & Information Policy Institute, The University of Texas at Austin

Flash floods like the one that swept down the Guadalupe River in Texas on July 4, 2025, can be highly unpredictable. While there are sophisticated flood prediction models and different types of warning systems in some places, effective flood protection requires extensive preparedness and awareness.

It also requires an understanding of how people receive, interpret and act on risk information and warnings. Technology can be part of the solution, but ultimately people are the critical element in any response.

As researchers who study emergency communications, we have found that simply providing people with technical information and data is often not enough to effectively communicate the danger and prompt them to act.

The human element

One of us, Keri Stephens, has led teams studying flood risk communication. They found that people who have experienced a flood are more aware of the risks. Conversely, groups that have not lived through floods typically don’t understanding various flood risks such as storm surges and flash floods. And while first responders often engage in table-top exercises and drills – very important for their readiness to respond – there are only a few examples of entire communities actively participating in warning drills.

Messages used to communicate flood risk also matter, but people need to receive them. To that end, Keri’s teams have worked with the Texas Water Development Board to develop resources that help local flood officials sort through and prioritize information about a flood hazard so they can share what is most valuable with their local communities.

The commonly used “Turn Around Don’t Drown” message, while valuable, may not resonate equally with all groups. Newly developed and tested messages such as “Keep Your Car High and Dry” appeal specifically to young adults who typically feel invincible but don’t want their prized vehicles damaged. While more research is needed, this is an example of progress in understanding an important aspect of flood communication: how recipients of the information make decisions.

Interviews conducted by researchers often include responses along these lines: “Another flash flood warning. We get these all the time. It’s never about flooding where I am.” This common refrain reveals a fundamental challenge in flood communication. When people hear “flood warning,” they often think of different things, and interpretations can vary depending on a person’s proximity to the flooding event.

Some people equate flood warnings with streamflow gauges and sensors that monitor water levels – the technical infrastructure that triggers alerts when rivers exceed certain thresholds. Others think of mobile phone alerts, county- or geographic-specific notification systems, or even sirens.

Beyond technologies and digital communication, warnings still come through informal networks in many communities. Emergency managers directly coordinate with and share information with major businesses and organizations, saying, “Hey, John, be sure you have somebody up tonight watching the National Weather Service alerts and rivers.”

This human-centered approach, similar to neighborhood-level systems we have studied in Japan, can provide direct confirmation that warnings have been received. This is something mass media and mobile systems cannot guarantee, especially during infrastructure failures such as power and cell tower outages.

Effective messages

Research shows that effective warning messages need to include five critical components: a clear hazard description, location-specific information, actionable guidance, timing cues and a credible source. The Federal Emergency Management Agency’s integrated public alert and warning system message design dashboard assists authorities in rapidly drafting effective messages.

This warning system, known as IPAWS, provides nationwide infrastructure for wireless emergency alerts and Emergency Alert System messages. While powerful, IPAWS has limitations − not all emergency managers are trained to use it, and messages may extend beyond intended geographic areas. Also, many older mobile devices lack the latest capabilities, so they may not receive the most complete messages when they are sent.

Hyperlocal community opt-in systems can complement IPAWS by allowing residents to register for targeted notifications. These systems, which can be run by communities or local agencies, face their own challenges. People must know they exist, be willing to share phone numbers, and remember to update their information. Social media platforms add another communication channel, with emergency managers increasingly using social media to share updates, though these primarily reach only certain demographics, and not everyone checks social media regularly.

The key is redundancy through multiple communication channels. Research has found that multiple warnings are needed for people to develop a sense of urgency, and the most effective strategy is simple: Tell another person what’s going on. Interpersonal networks help ensure the message is delivered and can prompt actions. As former Natural Hazards Center Director Dennis Mileti observed: The wireless emergency alerts system “is fast. Mama is faster.”

Warning fatigue

Professionals from the National Weather Service, FEMA and the Federal Communications Commission, along with researchers, are increasingly concerned about warning fatigue – when people tune out warnings because they receive too many of them.

However, there is limited empirical data about how and when people experience warning fatigue – or about its impact.

This creates a double bind: Officials have an obligation to warn people at risk, yet frequent warnings can desensitize recipients. More research is needed to determine the behavioral implications of and differences between warnings that people perceive as irrelevant to their immediate geographic area versus those that genuinely don’t apply to them. This distinction becomes especially critical when people might drive into flooded areas outside their immediate vicinity.

The key to effective emergency communication is to develop messages that resonate with specific audiences and build community networks that complement technological systems. We are now studying how to do this effectively in the United States and internationally. It’s also important to apply behavioral insights to the design of every level of communication warning systems. And it’s important to remember to test not just the technology but the entire end-to-end system, from threat identification to community response.

Finally, maintaining true redundancy across multiple communication channels is an important strategy when trying to reach as many people as possible. Technology supports human decision-making, but it doesn’t replace it.

Keri K. Stephens’ research reported here has been externally funded by the Texas Water Development Board, Texas General Land Office, and the National Science Foundation. Results published are peer-reviewed, and opinions reflect those of the author, not the funder.

Hamilton Bean has earned research funding from U.S. Department of Homeland Security and the National Oceanic and Atmospheric Administration. Results published are peer-reviewed, and opinions reflect those of the author, not the funder.

– ref. Why it can be hard to warn people about dangers like floods – communication researchers explain the role of human behavior – https://theconversation.com/why-it-can-be-hard-to-warn-people-about-dangers-like-floods-communication-researchers-explain-the-role-of-human-behavior-260780

Source: The Conversation – USA (3) – By Turgay Ayer, Professor of Industrial and Systems Engineering, Georgia Institute of Technology

Imagine walking into your doctor’s office feeling sick – and rather than flipping through pages of your medical history or running tests that take days, your doctor instantly pulls together data from your health records, genetic profile and wearable devices to help decipher what’s wrong.

This kind of rapid diagnosis is one of the big promises of artificial intelligence for use in health care. Proponents of the technology say that over the coming decades, AI has the potential to save hundreds of thousands, even millions of lives.

What’s more, a 2023 study found that if the health care industry significantly increased its use of AI, up to US$360 billion annually could be saved.

But though artificial intelligence has become nearly ubiquitous, from smartphones to chatbots to self-driving cars, its impact on health care so far has been relatively low.

A 2024 American Medical Association survey found that 66% of U.S. physicians had used AI tools in some capacity, up from 38% in 2023. But most of it was for administrative or low-risk support. And although 43% of U.S. health care organizations had added or expanded AI use in 2024, many implementations are still exploratory, particularly when it comes to medical decisions and diagnoses.

I’m a professor and researcher who studies AI and health care analytics. I’ll try to explain why AI’s growth will be gradual, and how technical limitations and ethical concerns stand in the way of AI’s widespread adoption by the medical industry.

Inaccurate diagnoses, racial bias

Artificial intelligence excels at finding patterns in large sets of data. In medicine, these patterns could signal early signs of disease that a human physician might overlook – or indicate the best treatment option, based on how other patients with similar symptoms and backgrounds responded. Ultimately, this will lead to faster, more accurate diagnoses and more personalized care.

AI can also help hospitals run more efficiently by analyzing workflows, predicting staffing needs and scheduling surgeries so that precious resources, such as operating rooms, are used most effectively. By streamlining tasks that take hours of human effort, AI can let health care professionals focus more on direct patient care.

But for all its power, AI can make mistakes. Although these systems are trained on data from real patients, they can struggle when encountering something unusual, or when data doesn’t perfectly match the patient in front of them.

As a result, AI doesn’t always give an accurate diagnosis. This problem is called algorithmic drift – when AI systems perform well in controlled settings but lose accuracy in real-world situations.

Racial and ethnic bias is another issue. If data includes bias because it doesn’t include enough patients of certain racial or ethnic groups, then AI might give inaccurate recommendations for them, leading to misdiagnoses. Some evidence suggests this has already happened.

Data-sharing concerns, unrealistic expectations

Health care systems are labyrinthian in their complexity. The prospect of integrating artificial intelligence into existing workflows is daunting; introducing a new technology like AI disrupts daily routines. Staff will need extra training to use AI tools effectively. Many hospitals, clinics and doctor’s offices simply don’t have the time, personnel, money or will to implement AI.

Also, many cutting-edge AI systems operate as opaque “black boxes.” They churn out recommendations, but even its developers might struggle to fully explain how. This opacity clashes with the needs of medicine, where decisions demand justification.

But developers are often reluctant to disclose their proprietary algorithms or data sources, both to protect intellectual property and because the complexity can be hard to distill. The lack of transparency feeds skepticism among practitioners, which then slows regulatory approval and erodes trust in AI outputs. Many experts argue that transparency is not just an ethical nicety but a practical necessity for adoption in health care settings.

There are also privacy concerns; data sharing could threaten patient confidentiality. To train algorithms or make predictions, medical AI systems often require huge amounts of patient data. If not handled properly, AI could expose sensitive health information, whether through data breaches or unintended use of patient records.

For instance, a clinician using a cloud-based AI assistant to draft a note must ensure no unauthorized party can access that patient’s data. U.S. regulations such as the HIPAA law impose strict rules on health data sharing, which means AI developers need robust safeguards.

Privacy concerns also extend to patients’ trust: If people fear their medical data might be misused by an algorithm, they may be less forthcoming or even refuse AI-guided care.

The grand promise of AI is a formidable barrier in itself. Expectations are tremendous. AI is often portrayed as a magical solution that can diagnose any disease and revolutionize the health care industry overnight. Unrealistic assumptions like that often lead to disappointment. AI may not immediately deliver on its promises.

Finally, developing an AI system that works well involves a lot of trial and error. AI systems must go through rigorous testing to make certain they’re safe and effective. This takes years, and even after a system is approved, adjustments may be needed as it encounters new types of data and real-world situations.

Incremental change

Today, hospitals are rapidly adopting AI scribes that listen during patient visits and automatically draft clinical notes, reducing paperwork and letting physicians spend more time with patients. Surveys show over 20% of physicians now use AI for writing progress notes or discharge summaries. AI is also becoming a quiet force in administrative work. Hospitals deploy AI chatbots to handle appointment scheduling, triage common patient questions and translate languages in real time.

Clinical uses of AI exist but are more limited. At some hospitals, AI is a second eye for radiologists looking for early signs of disease. But physicians are still reluctant to hand decisions over to machines; only about 12% of them currently rely on AI for diagnostic help.

Suffice to say that health care’s transition to AI will be incremental. Emerging technologies need time to mature, and the short-term needs of health care still outweigh long-term gains. In the meantime, AI’s potential to treat millions and save trillions awaits.

Turgay Ayer owns shares in Value Analytics Labs, a healthcare technology company. He received funding from government agencies, including NSF, NIH, and CDC.

– ref. AI in health care could save lives and money − but change won’t happen overnight – https://theconversation.com/ai-in-health-care-could-save-lives-and-money-but-change-wont-happen-overnight-241551

Source: The Conversation – USA (3) – By Jalees Rehman, Department Chair and Professor of Biochemistry and Molecular Genetics, University of Illinois Chicago

Tumors can destroy the blood vessels of muscles even when the muscles are nowhere close to the tumor. That is the key finding of a new study that my colleagues and I recently published in the journal Nature Cancer.

Muscle loss in cancer patients is a major health problem, but the exact causes of how precisely tumors affect muscles remain an active area of research.

Scientists in my lab were curious whether one explanation for the muscle loss in cancer patients could be that the cancer impairs the blood vessels that are necessary to supply nutrients and oxygen to muscles. Healthy blood vessels ensure that blood containing oxygen and nutrients is transported from the heart to all tissues and organs in the body, and then circulates back to the heart. Unhealthy blood vessels lose the ability to circulate sufficient blood and develop leaks, with nutrients seeping into the tissue prematurely and thereby cutting off the supply of nutrients to tissues that are further downstream.

To tackle this question, my colleagues and I worked with several other scientific research teams with expertise in advanced microscopy, cancer research and metabolism. We used animal models to study several kinds of tumors – lung cancer, skin cancer, colon cancer and pancreatic cancer. We consistently observed that the blood vessels in the muscles became fewer and leakier even before the muscle weakness set in.

We also found that tumors release a protein called Activin-A, which acts on blood vessels to cause the leakiness and, ultimately, loss of blood vessels in the muscle. When we used a gene therapy to restore blood vessel health by counteracting the effects of Activin-A, we were able to prevent the muscle loss.

So we examined the muscles of patients who had passed away because of cancer and found that the muscles of cancer patients contained fewer blood vessels than expected.

Why Activin-A matters

Millions of cancer survivors struggle with muscle weakness, which can be so profound that they may have difficulties walking up a couple of flights of stairs or going shopping for groceries on their own.

Severe muscle weakness and muscle loss during cancer is called cancer cachexia, which occurs in up to 80% of patients with advanced cancer.

Recent research indicates that cachexia is far more common among cancer patients than previously suspected, with approximately half the patients who see their cancer doctor for the first time already showing signs of muscle weakness.

Importantly, cachexia can persist even after the cancer is successfully treated and cured. This can have a devastating impact on the quality of life for cancer survivors.

Our discovery that the loss of blood vessel function in the muscles occurs early on during the progression of the cancer suggests that fixing blood vessels in cancer patients and cancer survivors could be a new way to prevent or reverse cachexia.

The reasons for the muscle loss in cancer are complicated and involve poor nutrition due to loss of appetite and inflammation, which are initially caused by the tumor but persist even when the tumor is removed.

What other research is being done

There are currently no treatments approved by the Food and Drug Administration for cachexia, but new therapies are on the horizon.

One such therapy is an antibody drug that targets the molecule GDF-15, a protein that is thought to suppress appetite.

Other studies are using a combination of targeted nutrition and exercise programs to help patients with cancer cachexia regain muscle mass and muscle strength.

All these studies suggest that we will need a combination of approaches to enhance exercise, nutrition, appetite, muscle regeneration and – as we propose – blood vessel health.

What’s next

We are now evaluating drugs and exercise programs that are known to improve blood vessel health. Repurposing these treatments that are traditionally designed for cardiovascular patients could be a rapid way to help cancer patients regain muscle strength.

We hope that our work highlights how important it is for cancer patients to receive comprehensive medical care, which includes improving cardiovascular health and overall quality of life.

The Research Brief is a short take on interesting academic work.

Jalees Rehman receives funding from the National Institutes of Health.

– ref. Muscle weakness in cancer survivors may be caused by treatable weakness in blood vessels – new research – https://theconversation.com/muscle-weakness-in-cancer-survivors-may-be-caused-by-treatable-weakness-in-blood-vessels-new-research-259765

Source: The Conversation – USA (3) – By Lloyd Hitoshi Mayer, Professor of Law, University of Notre Dame

Churches and other houses of worship can endorse political candidates without risking the loss of their tax-exempt status, the Internal Revenue Service said in a legal document the tax-collection agency filed on July 7, 2025. This guidance is at odds with a law Congress passed more than 70 years ago that’s known as the Johnson Amendment and applies to all charitable nonprofits, whether they are secular or religious.

The Conversation U.S. asked Lloyd Hitoshi Mayer, a law professor who has studied the regulation of churches’ political activities, to explain what this statute is, how the IRS seeks to change its purview and why this matters.

What’s the Johnson Amendment?

The Johnson Amendment is a provision that Lyndon B. Johnson added to a tax bill passed by Congress in 1954, when he was a senator. It says that any charity that wants to be tax-exempt under section 501(c)(3) of the Internal Revenue Code cannot “participate in, or intervene in … any political campaign on behalf of … any candidate for public office.” In the U.S., all houses of worship are designated as charities by the IRS.

The IRS has interpreted the Johnson Amendment for more than 70 years to mean that charities cannot speak in favor of political candidates or take any other action that supports or opposes them.

The IRS is prohibited from publicly disclosing audits of specific tax-exempt nonprofits under taxpayer privacy laws, so there’s no way to know the extent to which the law has been enforced. The public only learns about audits tied to possible Johnson Amendment violations if the nonprofit discloses that information or the IRS revoked their tax-exempt status.

However, the IRS did conduct a broad enforcement campaign in the 2000s known as the Political Activity Compliance Initiative. The reports it issued for 2004 and 2006 stated that it had audited hundreds of charities, including churches, for possible Johnson Amendment violations. The IRS generally found that most violations were minor and often inadvertent – warranting no more than a warning letter.

It’s unknown whether any nonprofits lost their tax-exempt status as a result of this initiative, which the IRS appears to have ended in 2008.

There’s only one known instance of a church losing its tax-exempt status because it violated the Johnson Amendment. In that case, a church in Binghamton, New York, published full-page newspaper ads criticizing Bill Clinton during his 1992 presidential campaign.

Why does the Trump administration want to change its enforcement?

The National Religious Broadcasters, two churches and another religious nonprofit sued the IRS in 2024, challenging the constitutionality of the Johnson Amendment on First Amendment free speech and free exercise of religion grounds and on Fifth Amendment due process grounds. The plaintiffs also argued that applying the Johnson Amendment to religious nonprofits violated the federal Religious Freedom Restoration Act.

The plaintiffs and the IRS filed a joint motion on July 7 to settle the case. They asked the U.S. District Court for the Eastern District of Texas to order the IRS not to enforce the Johnson Amendment against the two church plaintiffs. They also asked the court to incorporate in its order a statement that the Johnson Amendment does not apply to “speech by a house of worship to its congregation, in connection with religious services through its customary channels of communication on matters of faith, concerning electoral politics viewed through the lens of religious faith.”

This represents the first time the IRS has said there’s an exception to the Johnson Amendment for houses of worship. While lawmakers have periodically sought to repeal or modify the statute, neither chamber of Congress has ever passed such legislation.

President Donald Trump asserted during his first term that he had “gotten rid of” the Johnson Amendment. But that referred to his 2017 executive order that directed the Treasury Department – to which the IRS belongs – to respect freedom of religion with respect to religious organizations speaking about political issues as “consistent with law.”

Under the IRS interpretation of the Johnson Amendment at the time, it would not have been consistent with law for churches or other religious nonprofits to support or oppose candidates for elected public office.

How might the IRS treat religious political activity differently?

If the court approves this new joint motion, that order will only apply to the two churches that are plaintiffs in the case – not other religious nonprofits or the National Religious Broadcasters that joined them in suing the IRS. But the filing tells other houses of worship that the IRS will not enforce the Johnson Amendment against them for speech to their congregations, at least not during the Trump administration.

I think that the government may have a hard time applying this exception for several reasons.

The IRS will have to determine when a charity is a “church,” the term the IRS uses for a house of worship of any faith. That has become increasingly difficult in recent years, as some organizations that stretch the conventional definition of a church have won IRS recognition as such.

The IRS will also have to clarify what constitutes speech made “in connection with religious services” and what are “customary channels of communication.” For example, it’s unclear whether inviting a political candidate to address the congregation about how their religious faith relates to their candidacy falls within the exception.

Will only conservative politicians benefit?

Establishing this exception does not necessarily give conservative politicians any advantages.

It is true that recent attempts to repeal or modify the Johnson Amendment are associated with conservative Christian groups such as the Alliance Defending Freedom, which represented the plaintiffs in this lawsuit.

But historically, many progressive houses of worship have also pushed against the Johnson Amendment, including Black churches that often serve as political as well as religious centers for their communities.

A Texas Tribune and ProPublica investigation documented apparent violations of the Johnson Amendment in the 2022 midterm elections by almost 20 churches in Texas from across the political spectrum. Interestingly, most of the church leaders involved were aware of the amendment.

Many said they were not violating it because they avoided explicitly endorsing candidates, while at the same time clearly expressing their support for specific candidates by, for example, praying for an individual who was identified to the congregation as a candidate.

How could this new guidance change political campaigning?

Americans generally don’t want to see churches get involved in politics, including majorities in most denominations. Nonetheless, church leaders of all stripes who were already inclined to support particular candidates will probably feel emboldened to explicitly endorse candidates when preaching to their congregations.

There are two ways that this new exception could do more than that.

First, it isn’t limited to sermons by pastors, priests, rabbis, imams and other religious leaders. It extends to any speech to a house of worship’s congregation “in connection with religious services through its customary channels of communication on matters of faith.” It therefore almost certainly includes church bulletins and other written materials distributed as part of a religious service.

What’s less clear is whether “customary channels of communication” includes people who watch religious services streamed over the internet or on TV, rather than just those who attend services in person.

Second, the change will increase pressure on church leaders to support candidates.

For example, George W. Bush’s 2004 campaign reportedly sought to recruit thousands of congregations to distribute campaign information. It’s natural to expect such efforts to multiply and become more direct for both Democratic and Republican candidates from now on.

And church leaders will also likely face pressure from politically active congregants to endorse candidates, and have a harder time resisting it.

Lloyd Hitoshi Mayer previously worked at the law firm of Caplin & Drysdale, Chartered, including when the firm represented All Saints Episcopal Church of Pasadena, California with respect to an IRS audit of the church for allegedly violating the Johnson Amendment. He was not personally involved in this representation.

– ref. IRS says churches may endorse political candidates despite a decades-old federal statute barring them from doing that – https://theconversation.com/irs-says-churches-may-endorse-political-candidates-despite-a-decades-old-federal-statute-barring-them-from-doing-that-260854

Source: The Conversation – USA – By Mojtaba Akhavan-Tafti, Associate Research Scientist, University of Michigan

The burgeoning space industry and the technologies society increasingly relies on – electric grids, aviation and telecommunications – are all vulnerable to the same threat: space weather.

Space weather encompasses any variations in the space environment between the Sun and Earth. One common type of space weather event is called an interplanetary coronal mass ejection.

These ejections are bundles of magnetic fields and particles that originate from the Sun. They can travel at speeds up to 1,242 miles per second (2,000 kilometers per second) and may cause geomagnetic storms.

They create beautiful aurora displays – like the northern lights you can sometimes see in the skies – but can also disrupt satellite operations, shut down the electric grid and expose astronauts aboard future crewed missions to the Moon and Mars to lethal doses of radiation.

I’m a heliophysicist and space weather expert, and my team is leading the development of a next-generation satellite constellation called SWIFT, which is designed to predict potentially dangerous space weather events in advance. Our goal is to forecast extreme space weather more accurately and earlier.

The dangers of space weather

Commercial interests now make up a big part of space exploration, focusing on space tourism, building satellite networks, and working toward extracting resources from the Moon and nearby asteroids.

Space is also a critical domain for military operations. Satellites provide essential capabilities for military communication, surveillance, navigation and intelligence.

As countries such as the U.S. grow to depend on infrastructure in space, extreme space weather events pose a greater threat. Today, space weather threatens up to US$2.7 trillion in assets globally.

In September 1859, the most powerful recorded space weather event, known as the Carrington event, caused fires in North America and Europe by supercharging telegraph lines. In August 1972, another Carrington-like event nearly struck the astronauts orbiting the Moon. The radiation dose could have been fatal. More recently, in February 2022, SpaceX lost 39 of its 49 newly launched Starlink satellites because of a moderate space weather event.

Today’s space weather monitors

Space weather services heavily rely on satellites that monitor the solar wind, which is made up of magnetic field lines and particles coming from the Sun, and communicate their observations back to Earth. Scientists can then compare those observations with historical records to predict space weather and explore how the Earth may respond to the observed changes in the solar wind.

Earth’s magnetic field naturally protects living things and Earth-orbiting satellites from most adverse effects of space weather. However, extreme space weather events may compress – or in some cases, peel back – the Earth’s magnetic shield.

This process allows solar wind particles to make it into our protected environment – the magnetosphere – exposing satellites and astronauts onboard space stations to harsh conditions.

Most satellites that continuously monitor Earth-bound space weather orbit relatively close to the planet. Some satellites are positioned in low Earth orbit, about 100 miles (161 kilometers) above Earth’s surface, while others are in geosynchronous orbit, approximately 25,000 miles (40,000 km) away.

At these distances, the satellites remain within Earth’s protective magnetic shield and can reliably measure the planet’s response to space weather conditions. However, to more directly study incoming solar wind, researchers use additional satellites located farther upstream – hundreds of thousands of miles from Earth.

The U.S., the European Space Agency and India all operate space weather monitoring satellites positioned around the L1 Lagrange point – nearly 900,000 miles (1,450,000 km) from Earth – where the gravitational forces of the Sun and Earth balance. From this vantage point, space weather monitors can provide up to 40 minutes of advance warning for incoming solar events.

Advance warning for space weather

Increasing the warning time beyond 40 minutes – the current warning time – would help satellite operators, electric grid planners, flight directors, astronauts and Space Force officers better prepare for extreme space weather events.

For instance, during geomagnetic storms, the atmosphere heats up and expands, increasing drag on satellites in low Earth orbit. With enough advance warning, operators can update their drag calculations to prevent satellites from descending and burning up during these events. With the updated drag calculations, satellite operators could use the satellites’ propulsion systems to maneuver them higher up in orbit.

Airlines could change their routes to avoid exposing passengers and staff to high radiation doses during geomagnetic storms. And future astronauts on the way to or working on the Moon or Mars, which lack protection from these particles, could be alerted in advance to take cover.

Aurora lovers would also appreciate having more time to get to their favorite viewing destinations.

The Space Weather Investigation Frontier

My team and I have been developing a new space weather satellite constellation, named the Space Weather Investigation Frontier. SWIFT will, for the first time, place a space weather monitor beyond the L1 point, at 1.3 million miles (2.1 million kilometers) from Earth. This distance would allow scientists to inform decision-makers of any Earth-bound space weather events up to nearly 60 minutes before arrival.

Satellites with traditional chemical and electric propulsion systems cannot maintain an orbit at that location – farther from Earth and closer to the Sun – for long. This is because they would need to continuously burn fuel to counteract the Sun’s gravitational pull.

To address this issue, our team has spent decades designing and developing a new propulsion system. Our solution is designed to affordably reach a distance that is closer to the Sun than the traditional L1 point, and to operate there reliably for more than a decade by harnessing an abundant and reliable resource – sunlight.

SWIFT would use a fuelless propulsion system called a solar sail to reach its orbit. A solar sail is a hair-thin reflective surface – simulating a very thin mirror – that spans about a third of a football field. It balances the force of light particles coming from the Sun, which pushes it away, with the Sun’s gravity, which pulls it inward.

While a sailboat harnesses the lift created by wind flowing over its curved sails to move across water, a solar sail uses the momentum of photons from sunlight, reflected off its large, shiny sail, to propel a spacecraft through space. Both the sailboat and solar sail exploit the transfer of energy from their respective environments to drive motion without relying on traditional propellants.

A solar sail could enable SWIFT to enter an otherwise unstable sub-L1 orbit without the risk of running out of fuel.

NASA successfully launched its first solar sail in 2010. This in-space demonstration, named NanoSail-D2, featured a 107-square-foot (10 m² ) sail and was placed in low Earth orbit. That same year, the Japanese Space Agency launched a larger solar sail mission, IKAROS, which deployed a 2,110 ft² (196 m² ) sail in the solar wind and successfully orbited Venus.

The Planetary Society and NASA followed up by launching two sails in low Earth orbit: LightSail, with an area of 344 ft² (32 m² ), and the advanced composite solar sail system, with an area of 860 ft² (80 m² ).

The SWIFT team’s solar sail demonstration mission, Solar Cruiser, will be equipped with a much larger sail – it will have area of 17,793 ft² (1,653 m² ) and launch as early as 2029. We successfully deployed a quadrant of the sail on Earth early last year.

To transport it to space, the team will meticulously fold and tightly pack the sail inside a small canister. The biggest challenge to overcome will be deploying the sail once in space and using it to guide the satellite along its orbital path.

If successful, Solar Cruiser will pave the way for SWIFT’s constellation of four satellites. The constellation would include one satellite equipped with sail propulsion, set to be placed in an orbit beyond L1, and three smaller satellites with chemical propulsion in orbit at the L1 Lagrange point.

The satellites will be indefinitely parked at and beyond L1, collecting data in the solar wind without interruption. Each of the four satellites can observe the solar wind from different locations, helping scientists better predict how it may evolve before reaching Earth.

As modern life depends more on space infrastructure, continuing to invest in space weather prediction can protect both space- and ground-based technologies.

Mojtaba Akhavan-Tafti receives funding from NASA. He is the Principal Investigator of Space Weather Investigation Frontier (SWIFT).

– ref. Spacecraft equipped with a solar sail could deliver earlier warnings of space weather threats to Earth’s technologies – https://theconversation.com/spacecraft-equipped-with-a-solar-sail-could-deliver-earlier-warnings-of-space-weather-threats-to-earths-technologies-259877