theconversation.com – James Wray, Professor of Earth and Atmospheric Sciences, Georgia Institute of Technology – 2024-10-11 12:36:00
The human mind may find it difficult to conceptualize: a cosmic cloud so colossal it surrounds the Sun and eight planets as it extends trillions of miles into deep space.
The spherical shell known as the Oort Cloud is, for all practical purposes, invisible. Its constituent particles are spread so thinly, and so far from the light of any star, including the Sun, that astronomers simply cannot see the cloud, even though it envelops us like a blanket.
It is also theoretical. Astronomers infer the Oort Cloud is there because it’s the only logical explanation for the arrival of a certain class of comets that sporadically visit our solar system. The cloud, it turns out, is basically a gigantic reservoir that may hold billions of icy celestial bodies.
Two of those bodies will pass by Earth in the days leading up to Halloween. Tsuchinshan-ATLAS, also known as Comet C/2023 A3, will be at its brightest, and likely visible to the naked eye, for a week or two after Oct. 12, the day it’s closest to Earth – just look to the western sky shortly after sunset. As the days pass, the comet will get fainter and move to a higher part of the sky.
The second comet, C/2024 S1 (ATLAS), just discovered on Sept. 27, should be visible around the end of October. The comet will pass closest to Earth on Oct. 24 – look low in the eastern sky just before sunrise. Then, after swinging around the Sun, the comet may reappear in the western night sky right around Halloween. It’s possible, however, that it could disintegrate, in part or in whole, as sometimes happens when comets pass by the Sun – and this one will come within 1 million miles (1.6 million kilometers) of our star.
As a planetary astronomer, I’m particularly curious about the Oort Cloud and the icy bodies inhabiting it. The Cloud’s residents may be a reason why life ignited on Earth; crashing on our planet eons ago, these ice bodies may have supplied at least some of the water that all life requires. At the same time, these same objects pose an ever-present threat to Earth’s continuation – and our survival.
Billions of comets
If an Oort Cloud object finds its way to the inner solar system, its ices vaporize. That process produces a tail of debris that becomes visible as a comet.
Some of these bodies, known as long-period comets, have orbits of hundreds, thousands or even millions of years, like Tsuchinshan-ATLAS. This is unlike the so-called short-period comets, which do not visit the Oort Cloud and have comparatively quick orbits. Halley’s comet, which cuts a path through the solar system and orbits the Sun every 76 years or so, is one of them.
The 20th-century Dutch astronomer Jan Oort, intrigued by the long-period comets, wrote a paper on them in 1950. He noted about 20 of the comets had an average distance from the Sun that was more than 10,000 astronomical units. This was astounding; just one AU is the distance of the Earth from the Sun, which is about 93 million miles. Multiply 93 million by 10,000, and you’ll find these comets come from over a trillion miles away. What’s more, Oort suggested, they were not necessarily the cloud’s outermost objects.
Nearly 75 years after Oort’s paper, astronomers still can’t directly image this part of space. But they do estimate the Oort Cloud spans up to 10 trillion miles from the Sun, which is almost halfway to Proxima Centauri, the next closest star.
The long-period comets spend most of their time at those vast distances, making only brief and rapid visits close to the Sun as they come in from all directions. Oort speculated the cloud contained 100 billion of these icy objects. That may be as numerous as the number of stars in our galaxy.
How did they get there? Oort suggested, and modern simulations have confirmed, that these icy bodies could have initially formed near Jupiter, the solar system’s largest planet. Perhaps these objects had their orbits around the Sun disturbed by Jupiter – similar to how NASA spacecraft bound for destinations from Saturn to Pluto have typically swung by the giant planet to accelerate their journeys outward.
Some of these objects would have escaped the solar system permanently, becoming interstellar objects. But others would have ended up with orbits like those of the long-period comets.
Threats to Earth
Long-period comets present a particular potential danger to Earth. Because they are so far from our Sun, their orbits are readily altered by the gravity of other stars. That means scientists have no idea when or where one will appear, until it does, suddenly. By then, it’s typically closer than Jupiter and moving rapidly, at tens of thousands of miles per hour. Indeed, the fictional comet that doomed Earth in the film “Don’t Look Up” came from the Oort Cloud.
New Oort Cloud comets are discovered all the time, a dozen or so per year in recent years. The odds of any of them colliding with Earth are extremely low. But it is possible. The recent success of NASA’s DART mission, which altered the orbit of a small asteroid, demonstrates one plausible approach to fending off these small bodies. But that mission was developed after years of studying its target. A comet from the Oort Cloud may not offer that much time – maybe just months, weeks or even days.
Or no time at all. ‘Oumuamua, the odd little object that visited our solar system in 2017, was discovered not before but after its closest approach to Earth. Although ‘Oumuamua is an interstellar object, and not from the Oort Cloud, the proposition still applies; one of these objects could sneak up on us, and the Earth would be defenseless.
One way to prepare for these objects is to better understand their basic properties, including their size and composition. Toward this end, my colleagues and I work to characterize new long-period comets. The largest known one, Bernardinelli–Bernstein, discovered just three years ago, is roughly 75 miles (120 kilometers) across. Most known comets are much smaller, from one to a few miles, and some smaller ones are too faint for us to see. But newer telescopes are helping. In particular, the Rubin Observatory’s decade-long Legacy Survey of Space and Time, starting up in 2025, may double the list of known Oort Cloud comets, which now stands at about 4,500.
The unpredictability of these objects makes them a challenging target for spacecraft, but the European Space Agency is preparing a mission to do just that: Comet Interceptor. With a launch planned for 2029, the probe will park in space until a suitable target from the Oort Cloud appears. Studying one of these ancient and pristine objects could offer scientists clues about the origins of the solar system.
As for the comets now in Earth’s vicinity, it’s OK to look up. Unlike the comet in the DiCaprio movie, these two will not crash into the Earth. The nearest Tsuchinshan-ATLAS will get to us is about 44 million miles (70 million kilometers); C/2024 S1 (ATLAS), about 80 million miles (130 million kilometers). Sounds like a long way, but in space, that’s a near miss.
theconversation.com – John Sommers-Flanagan, Clinical Psychologist and Professor of Counseling, University of Montana – 2024-10-11 07:32:00
Uncommon Courses is an occasional series from The Conversation U.S. highlighting unconventional approaches to teaching.
Title of Course
Evidence-Based Happiness for Teachers
What prompted the idea for the course?
I was discouraged. For nearly three decades, as a clinical psychologist, I trained mental health professionals on suicide assessment. The work was good but difficult.
I consulted my wife, Rita, who also happens to be my favorite clinical psychologist. We decided to explore the science of happiness. Together, we established the Montana Happiness Project and began offering evidence-based happiness workshops to complement our suicide prevention work.
In 2021, the Arthur M. Blank Family Foundation, through the University of Montana, awarded us a US$150,000 grant to support the state’s K-12 public school teachers, counselors and staff. We’re using the funds to offer these educators low-cost, online graduate courses on happiness. In spring 2023, the foundation awarded us another $150,000 so we could extend the program through December 2025.
What does the course explore?
Using the word “happiness” can be off-putting. Sometimes, people associate happiness with recommendations to just smile, cheer up and suppress negative emotions – which can lead to toxic positivity.
As mental health professionals, my wife and I reject that definition. Instead, we embrace Aristotle’s concept of “eudaimonic happiness”: the daily pursuit of meaning, mutually supportive relationships and becoming the best possible version of yourself.
The heart of the course is an academic, personal and experiential exploration of evidence-based positive psychology interventions. These are intentional practices that can improve mood, optimism, relationships and physical wellness and offer a sense of purpose. Examples include gratitude, acts of kindness, savoring, mindfulness, mood music, practicing forgiveness and journaling about your best possible future self.
Students are required to implement at least 10 of 14 positive psychology interventions, and then to talk and write about their experiences on implementing them.
The lesson on sleep is especially powerful for educators. A review of 33 studies from 15 countries reported that 36% to 61% of K-12 teachers suffered from insomnia. Although the rates varied across studies, sleep problems were generally worse when teachers were exposed to classroom violence, had low job satisfaction and were experiencing depressive symptoms.
The sleep lesson includes, along with sleep hygiene strategies, a happiness practice and insomnia intervention called Three Good Things, developed by the renowned positive psychologist Martin Seligman.
I describe the technique, in Seligman’s words: “Write down, for one week, before you go to sleep, three things that went well for you during the day, and then reflect on why they went well.”
Next, I make light of the concept: “I’ve always thought Three Good Things was hokey, simplistic and silly.” I show a video of Seligman saying, “I don’t need to recommend beyond a week, typically … because when you do this, you find you like it so much, most people just keep doing it.” At that point, I roll my eyes and say, “Maybe.”
Then I share that I often awakened for years at 4 a.m. with terribly dark thoughts. Then – funny thing – I tried using Three Good Things in the middle of the night. It wasn’t a perfect solution, but it was a vast improvement over lying helplessly in bed while negative thoughts pummeled me.
The Three Good Things lesson is emblematic of how we encourage teachers in our course – using science, playful cynicism and an open and experimental mindset to apply the evidence-based happiness practices in ways that work for them.
I also encourage students to understand that the strategies I offer are not universally effective. What works for others may not work for them, which is why they should experiment with many different approaches.
What will the course prepare students to do?
The educators leave the course with a written lesson plan they can implement at their school, if they wish. As they deepen their happiness practice, they can also share it with other teachers, their students and their families.
Over the past 16 months, we’ve taught this course to 156 K-12 educators and other school personnel. In a not-yet-published survey that we carried out, more than 30% of the participants scored as clinically depressed prior to starting the class, compared with just under 13% immediately after the class.
The educators also reported overall better health after taking the class. Along with improved sleep, they took fewer sick days, experienced fewer headaches and reported reductions in cold, flu and stomach symptoms.
As resources allow, we plan to tailor these courses to other people with high-stress jobs. Already, we are receiving requests from police officers, health care providers, veterinarians and construction workers.
The 67 million Americans eligible for Medicare make an important decision every October: Should they make changes in their Medicare health insurance plans for the next calendar year?
The decision is complicated. Medicare has an enormous variety of coverage options, with large and varying implications for people’s health and finances, both as beneficiaries and taxpayers. And the decision is consequential – some choices lock beneficiaries out of traditional Medicare.
Beneficiaries choose an insurance plan when they turn 65 or become eligible based on qualifying chronic conditions or disabilities. After the initial sign-up, most beneficiaries can make changes only during the open enrollment period each fall.
The 2024 open enrollment period, which runs from Oct. 15 to Dec. 7, marks an opportunity to reassess options. Given the complicated nature of Medicare and the scarcity of unbiased advisers, however, finding reliable information and understanding the options available can be challenging.
We are health carepolicy experts who study Medicare, and even we find it complicated. One of us recently helped a relative enroll in Medicare for the first time. She’s healthy, has access to health insurance through her employer and doesn’t regularly take prescription drugs. Even in this straightforward scenario, the number of choices were overwhelming.
The stakes of these choices are even higher for people managing multiple chronic conditions. There is help available for beneficiaries, but we have found that there is considerable room for improvement – especially in making help available for everyone who needs it.
The choice is complex, especially when you are signing up for the first time and if you are eligible for both Medicare and Medicaid. Insurers often engage in aggressive and sometimes deceptive advertising and outreach through brokers and agents. Choose unbiased resources to guide you through the process, like www.shiphelp.org. Make sure to start before your 65th birthday for initial sign-up, look out for yearly plan changes, and start well before the Dec. 7 deadline for any plan changes.
2 paths with many decisions
Within Medicare, beneficiaries have a choice between two very different programs. They can enroll in either traditional Medicare, which is administered by the government, or one of the Medicare Advantage plans offered by private insurance companies.
Within each program are dozens of further choices.
Traditional Medicare is a nationally uniform cost-sharing plan for medical services that allows people to choose their providers for most types of medical care, usually without prior authorization. Deductibles for 2024 are US$1,632 for hospital costs and $240 for outpatient and medical costs. Patients also have to chip in starting on Day 61 for a hospital stay and Day 21 for a skilled nursing facility stay. This percentage is known as coinsurance. After the yearly deductible, Medicare pays 80% of outpatient and medical costs, leaving the person with a 20% copayment. Traditional Medicare’s basic plan, known as Part A and Part B, also has no out-of-pocket maximum.
People enrolled in traditional Medicare can also purchase supplemental coverage from a private insurance company, known as Part D, for drugs. And they can purchase supplemental coverage, known as Medigap, to lower or eliminate their deductibles, coinsurance and copayments, cap costs for Parts A and B, and add an emergency foreign travel benefit.
The Medicare Advantage program allows private insurers to bundle everything together and offers many enrollment options. Compared with traditional Medicare, Medicare Advantage plans typically offer lower out-of-pocket costs. They often bundle supplemental coverage for hearing, vision and dental, which is not part of traditional Medicare.
Different Medicare Advantage plans have varying and large impacts on enrollee health, including dramatic differences in mortality rates. Researchers found a 16% difference per year between the best and worst Medicare Advantage plans, meaning that for every 100 people in the worst plans who die within a year, they would expect only 84 people to die within that year if all had been enrolled in the best plans instead. They also found plans that cost more had lower mortality rates, but plans that had higher federal quality ratings – known as “star ratings” – did not necessarily have lower mortality rates.
While many Medicare Advantage plans boast about their supplemental benefits , such as vision and dental coverage, it’s often difficult to understand how generous this supplemental coverage is. For instance, while most Medicare Advantage plans offer supplemental dental benefits, cost-sharing and coverage can vary. Some plans don’t cover services such as extractions and endodontics, which includes root canals. Most plans that cover these more extensive dental services require some combination of coinsurance, copayments and annual limits.
Even when information is fully available, mistakes are likely.
At 65, when most beneficiaries first enroll in Medicare, federal regulations guarantee that anyone can get Medigap coverage. During this initial sign-up, beneficiaries can’t be charged a higher premium based on their health.
Older Americans who enroll in a Medicare Advantage plan but then want to switch back to traditional Medicare after more than a year has passed lose that guarantee. This can effectively lock them out of enrolling in supplemental Medigap insurance, making the initial decision a one-way street.
For the initial sign-up, Medigap plans are “guaranteed issue,” meaning the plan must cover preexisting health conditions without a waiting period and must allow anyone to enroll, regardless of health. They also must be “community rated,” meaning that the cost of a plan can’t rise because of age or illness, although it can go up due to other factors such as inflation.
People who enroll in traditional Medicare and a supplemental Medigap plan at 65 can expect to continue paying community-rated premiums as long as they remain enrolled, regardless of what happens to their health.
Information about Medicare coverage and assistance choosing a plan is available but varies in quality and completeness. Older Americans are bombarded with ads for Medicare Advantage plans that they may not be eligible for and that include misleading statements about benefits.
A November 2022 report from the U.S. Senate Committee on Finance found deceptive and aggressive sales and marketing tactics, including mailed brochures that implied government endorsement, telemarketers who called up to 20 times a day, and salespeople who approached older adults in the grocery store to ask about their insurance coverage.
The Department of Health and Human Services tightened rules for 2024, requiring third-party marketers to include federal resources about Medicare, including the website and toll-free phone number, and limiting the number of contacts from marketers.
Although the government has the authority to review marketing materials, enforcement is partially dependent on whether complaints are filed. Complaints can be filed with the federal government’s Senior Medicare Patrol, a federally funded program that prevents and addresses unethical Medicare activities.
Nearly one-third of Medicare beneficiaries seek information from an insurance broker. Brokers sell health insurance plans from multiple companies. However, because they receive payment from plans in exchange for sales, and because they are unlikely to sell every option, a plan recommended by a broker may not meet a person’s needs.
Help is out there − but falls short
An alternative source of information is the federal government. It offers three sources of information to assist people with choosing one of these plans: 1-800-Medicare, medicare.gov and the State Health Insurance Assistance Program, also known as SHIP.
Telephone SHIP services are available nationally, but one of us and our colleagues have found that in-person SHIP services are not available in some areas. We tabulated areas by ZIP code in 27 states and found that although more than half of the locations had a SHIP site within the county, areas without a SHIP site included a larger proportion of people with low incomes.
Virtual services are an option that’s particularly useful in rural areas and for people with limited mobility or little access to transportation, but they require online access. Virtual and in-person services, where both a beneficiary and a counselor can look at the same computer screen, are especially useful for looking through complex coverage options.
As one SHIP coordinator noted, many people are not aware of all their coverage options. For instance, one beneficiary told a coordinator, “I’ve been on Medicaid and I’m aging out of Medicaid. And I don’t have a lot of money. And now I have to pay for my insurance?” As it turned out, the beneficiary was eligible for both Medicaid and Medicare because of their income, and so had to pay less than they thought.
The interviews made clear that many people are not aware that Medicare Advantage ads and insurance brokers may be biased. One counselor said, “There’s a lot of backing (beneficiaries) off the ledge, if you will, thanks to those TV commercials.”
Many SHIP staff counselors said they would benefit from additional training on coverage options, including for people who are eligible for both Medicare and Medicaid. The SHIP program relies heavily on volunteers, and there is often greater demand for services than the available volunteers can offer. Additional counselors would help meet needs for complex coverage decisions.
The key to making a good Medicare coverage decision is to use the help available and weigh your costs, access to health providers, current health and medication needs, and also consider how your health and medication needs might change as time goes on.
This article is part of an occasional series examining the U.S. Medicare system.
This story has been updated to remove a graphic that contained incorrect information about SHIP locations, and to correct the date of the open enrollment period.
This year’s award stood out because it honored research that originated at a tech company: DeepMind, an AI research startup that was acquired by Google in 2014. Most previous chemistry Nobel Prizes have gone to researchers in academia. Many laureates went on to form startup companies to further expand and commercialize their groundbreaking work – for instance, CRISPR gene-editing technology and quantum dots – but the research, from start to end, wasn’t done in the commercial sphere.
Although the Nobel Prizes in physics and chemistry are awarded separately, there is a fascinating connection between the winning research in those fields in 2024. The physics award went to two computer scientists who laid the foundations for machine learning, while the chemistry laureates were rewarded for their use of machine learning to tackle one of biology’s biggest mysteries: how proteins fold.
The 2024 Nobel Prizes underscore both the importance of this kind of artificial intelligence and how science today often crosses traditional boundaries, blending different fields to achieve groundbreaking results.
The challenge of protein folding
Proteins are the molecular machines of life. They make up a significant portion of our bodies, including muscles, enzymes, hormones, blood, hair and cartilage.
Understanding proteins’ structures is essential because their shapes determine their functions. Back in 1972, Christian Anfinsen won the Nobel Prize in chemistry for showing that the sequence of a protein’s amino acid building blocks dictates the protein’s shape, which, in turn, influences its function. If a protein folds incorrectly, it may not work properly and could lead to diseases such as Alzheimer’s, cystic fibrosis or diabetes.
A protein’s overall shape depends on the tiny interactions, the attractions and repulsions, between all the atoms in the amino acids its made of. Some want to be together, some don’t. The protein twists and folds itself into a final shape based on many thousands of these chemical interactions.
For decades, one of biology’s greatest challenges was predicting a protein’s shape based solely on its amino acid sequence. Although researchers can now predict the shape, we still don’t understand how the proteins maneuver into their specific shapes and minimize the repulsions of all the interatomic interactions in a few microseconds.
To understand how proteins work and to prevent misfolding, scientists needed a way to predict the way proteins fold, but solving this puzzle was no easy task.
In 2003, University of Washington biochemist David Baker wrote Rosetta, a computer program for designing proteins. With it he showed it was possible to reverse the protein-folding problem by designing a protein shape and then predicting the amino acid sequence needed to create it.
It was a phenomenal jump forward, but the shape chosen for the calculation was simple, and the calculations were complex. A major paradigm shift was required to routinely design novel proteins with desired structures.
A new era of machine learning
Machine learning is a type of AI where computers learn to solve problems by analyzing vast amounts of data. It’s been used in various fields, from game-playing and speech recognition to autonomous vehicles and scientific research. The idea behind machine learning is to use hidden patterns in data to answer complex questions.
This approach made a huge leap in 2010 when Demis Hassabis co-founded DeepMind, a company aiming to combine neuroscience with AI to solve real-world problems.
Hassabis, a chess prodigy at age 4, quickly made headlines with AlphaZero, an AI that taught itself to play chess at a superhuman level. In 2017, AlphaZero thoroughly beat the world’s top computer chess program, Stockfish-8. The AI’s ability to learn from its own gameplay, rather than relying on preprogrammed strategies, marked a turning point in the AI world.
Soon after, DeepMind applied similar techniques to Go, an ancient board game known for its immense complexity. In 2016, its AI program AlphaGo defeated one of the world’s top players, Lee Sedol, in a widely watched match that stunned millions.
In 2016, Hassabis shifted DeepMind’s focus to a new challenge: the protein-folding problem. Under the leadership of John Jumper, a chemist with a background in protein science, the AlphaFold project began. The team used a large database of experimentally determined protein structures to train the AI, which allowed it to learn the principles of protein folding. The result was AlphaFold2, an AI that could predict the 3D structure of proteins from their amino acid sequences with remarkable accuracy.
This was a significant scientific breakthrough. AlphaFold has since predicted the structures of over 200 million proteins – essentially all the proteins that scientists have sequenced to date. This massive database of protein structures is now freely available, accelerating research in biology, medicine and drug development.
Designer proteins to fight disease
Understanding how proteins fold and function is crucial for designing new drugs. Enzymes, a type of protein, act as catalysts in biochemical reactions and can speed up or regulate these processes. To treat diseases such as cancer or diabetes, researchers often target specific enzymes involved in disease pathways. By predicting the shape of a protein, scientists can figure out where small molecules – potential drug candidates – might bind to it, which is the first step in designing new medicines.
In 2024, DeepMind launched AlphaFold3, an upgraded version of the AlphaFold program that not only predicts protein shapes but also identifies potential binding sites for small molecules. This advance makes it easier for researchers to design drugs that precisely target the right proteins.
For his part, David Baker has continued to make significant contributions to protein science. His team at the University of Washington developed an AI-based method called “family-wide hallucination,” which they used to design entirely new proteins from scratch. Hallucinations are new patterns – in this case, proteins – that are plausible, meaning they are a good fit with patterns in the AI’s training data. These new proteins included a light-emitting enzyme, demonstrating that machine learning can help create novel synthetic proteins. These AI tools offer new ways to design functional enzymes and other proteins that never could have evolved naturally.
AI will enable research’s next chapter
The Nobel-worthy achievements of Hassabis, Jumper and Baker show that machine learning isn’t just a tool for computer scientists – it’s now an essential part of the future of biology and medicine.
By tackling one of the toughest problems in biology, the winners of the 2024 prize have opened up new possibilities in drug discovery, personalized medicine and even our understanding of the chemistry of life itself.