Meet Irene Curie, the Nobel-winning atomic physicist who changed the course of modern cancer treatment
Artemis Spyrou, Michigan State University and Andrea Richard, Ohio University The adage goes “like mother like daughter,” and in the case of Irene Joliot-Curie, truer words were never spoken. She was the daughter of two Nobel Prize laureates, Marie Curie and Pierre Curie, and was herself awarded the Nobel Prize in chemistry in 1935 together with her husband, Frederic Joliot. While her parents received the prize for the discovery of natural radioactivity, Irene’s prize was for the synthesis of artificial radioactivity. This discovery changed many fields of science and many aspects of our everyday lives. Artificial radioactivity is used today in medicine, agriculture, energy production, food sterilization, industrial quality control and more.Frederic Joliot and Irene Joliot-Curie.Wellcome Collection, CC BY We are two nuclear physicistswho perform experiments at different accelerator facilities around the world. Irene’s discovery laid the foundation for our experimental studies, which use artificial radioactivity to understand questions related to astrophysics, energy, medicine and more.
Early years and battlefield training
Irene Curie was born in Paris, France, in 1897. In an unusual schooling setup, Irene was one of a group of children taught by their academic parents, including her own by then famous mother, Marie Curie.Marie Curie and her daughter Irene were both scientists studying radioactivity.Wellcome Collection, CC BY World War I started in 1914, when Irene was only 17, and she interrupted her studies to help her mother find fragments of bombs in wounded soldiers using portable X-ray machines. She soon became an expert in these wartime radiology techniques, and on top of performing the measurements herself, she also spent time training nurses to use the X-ray machines. After the war, Irene went back to her studies in her mother’s lab at the Radium Institute. This is where she met fellow researcher Frederic Joliot, whom she later married. The two worked together on many projects, which led them to their major breakthrough in 1934.
A radioactive discovery
Isotopes are variations of a particular element that have the same number of protons – positively charged particles – and different numbers of neutrons, which are particles with no charge. While some isotopes are stable, the majority are radioactive and called radioisotopes. These radioisotopes spontaneously transform into different elements and release radiation – energetic particles or light – in a process called radioactive decay. At the time of Irene and Frederic’s discovery, the only known radioactive isotopes came from natural ores, through a costly and extremely time-consuming process. Marie and Pierre Curie had spent years studying the natural radioactivity in tons of uranium ores. In Irene and Frederic’s experiments, they bombarded aluminum samples with alpha particles, which consist of two protons and two neutrons bound together – they are atomic nuclei of the isotope helium-4. In previous studies, they had observed the different types of radiation their samples emitted while being bombarded. The radiation would cease when they took away the source of alpha particles. In the aluminum experiment, however, they noticed that even after they removed the alpha source, they could still detect radiation. The amount of radiation decreased by half every three minutes, and they concluded that the radiation came from the decay of a radioisotope of the element phosphorus. Phosphorus has two additional protons compared to aluminum and was formed when the alpha particles fused with the aluminum nuclei. This was the first identification of an artificially made radioisotope, phosphorus-30. Because phosphorus-30 was created after bombarding aluminum with alpha particles – rather than occurring in its natural state – Irene and Frederic induced the radioactivity. So, it is called artificial radioactivity.In Irene and Frederic’s experiments, an isotope of aluminum was hit with an alpha particle (two neutrons and two protons bound together). The collision resulted in two protons and a neutron from the alpha particle binding to the aluminum, making it an isotope of phosphorus, which decayed, releasing a particle called a positron.Artemis Spyrou After her major discovery, Irene stayed active not only in research but in activism and politics as well. In 1936, almost a decade before women gained the right to vote in France, she was appointed under secretary of state for scientific research. In this position, she laid the foundations for what would become the National Centre for Scientific Research, which is the French equivalent of the U.S. National Science Foundation or National Institutes of Health. She co-created the French Atomic Energy Commission in 1945 and held a six-year term, promoting nuclear research and development of the first French nuclear reactor. She later became director of the Curie Laboratory at the Radium Institute and a professor at the Faculty of Science in Paris.
Medical uses of artificial radioactivity
The Joliot-Curie discovery opened the road to the extensive use of radioisotopes in medical applications. Today, radioactive iodine is used regularly to treat thyroid diseases. Radioisotopes that emit positrons – the positive equivalent of the electron – are used in medical PET scans to image and diagnose cancer, and others are used for cancer therapy. To diagnose cancer, practitioners can inject a small amount of the radioisotope into the body, where it accumulates at specific organs. Specialized devices such as a PET scanner can then detect the radioactivity from the outside. This way, doctors can visualize how these organs are working without the need for surgery. To then treat cancer, practitioners use large amounts of radiation to kill the cancer cells. They try to localize the application of the radioisotope to just where the cancer is so that they’re only minimally affecting healthy tissue.
An enduring legacy
In the 90 years since the Joliot-Curie discovery of the first artificial radioisotope, the field of nuclear science has expanded its reach to roughly 3,000 artificial radioisotopes, from hydrogen to the heaviest known element, oganesson. However, nuclear theories predict that up to 7,000 artificial radioisotopes are possible. As physicists, we work with data from a new facility at Michigan State University, the Facility for Rare Isotope Beams, which is expected to discover up to 1,000 new radioisotopes.Scientists graph the known isotopes in the chart of nuclei. They have discovered roughly 3,000 radioisotopes (shown with cyan boxes) and predict the existence of another 4,000 radioisotopes (shown with gray boxes).Facility for Rare Isotope Beams While the Joliot-Curies were bombarding their samples with alpha particles at relatively low speeds, the Michigan State facility can accelerate stable isotopes up to half the speed of light and smash them on a target to produce new radioisotopes. Scientists using the facility have already discovered five new radioisotopes since it began operating in 2022, and the search continues. Each of the thousands of available radioisotopes has a different set of properties. They live for different amounts of time and emit different types of radiation and amounts of energy. This variability allows scientists to choose the right isotope for the right application. Iodine, for example, has more than 40 known radioisotopes. A main characteristic of radioisotopes is their half-life, meaning the amount of time it takes for half of the isotopes in the sample to transform into a new element. Iodine radioisotopes have half-lives that span from a tenth of a second to 16 million years. But not all of them are useful, practical or safe for thyroid treatment.The iodine radioisotope used in cancer therapy has a half-life of eight days. Eight days is long enough to kill cancer cells in the body, but not so long that the radioactivity poses a long-term threat to the patient and those around them.Artemis Spyrou Radioisotopes that live for a few seconds don’t exist long enough to perform medical procedures, and radioisotopes that live for years would harm the patient and their family. Because it lives for a few days, iodine-131 is the preferred medical radioisotope. Artificial radioactivity can also help scientists study the universe’s mysteries. For example, stars are fueled by nuclear reactions and radioactive decay in their cores. In violent stellar events, such as when a star explodes at the end of its life, they produce thousands of different radioisotopes that can drive the explosion. For this reason, scientists, including the two of us. produce and study in the lab the radioisotopes found in stars. With the advent of the Facility for Rare Isotope Beams and other accelerator facilities, the search for new radioisotopes will continue opening doors to a world of possibilities. Artemis Spyrou, Professor of Nuclear Physics, Michigan State University and Andrea Richard, Assistant Professor of Physics and Astronomy, Ohio University This article is republished from The Conversation under a Creative Commons license. Read the original article.
A Short-Form Series from The Knowledge by STM Daily News
Every Friday, STM Daily News shines a light on brilliant minds history overlooked.
Forgotten Genius Fridays is a weekly collection of short videos and articles dedicated to inventors, innovators, scientists, and creators whose impact changed the world—but whose names were often left out of the textbooks.
From life-saving inventions and cultural breakthroughs to game-changing ideas buried by bias, our series digs up the truth behind the minds that mattered.
Each episode of The Knowledge runs 30–90 seconds, designed for curious minds on the go—perfect for YouTube Shorts, TikTok, Reels, and quick reads.
Because remembering these stories isn’t just about the past—it’s about restoring credit where it’s long overdue.
Feeding America is marking National Agriculture Day by recognizing farmers, ranchers, and producers as key partners in the fight against hunger.
In a March 24 press release, the organization said the agricultural community plays a vital role in helping food banks and pantries deliver fresh, nutritious food to families across the country. Feeding America noted that produce, dairy, and protein are among the most requested foods by neighbors facing hunger and make up half of all food distributed through its network.
The organization said that in 2025, its network worked with growers to rescue 971 million pounds of fresh produce, helping redirect surplus food to communities in need. Feeding America also pointed to federal nutrition and farm support programs, saying government purchases from U.S. growers provide more than 20% of the food distributed through its network.
Ami McReynolds, Feeding America’s chief advocacy and community partnerships officer, said supporting farmers is directly connected to helping families access healthy meals. The organization is also urging Congress to support additional farm aid and a Farm Bill that strengthens nutrition programs.
Feeding America said a recent poll found that 95% of voters view hunger as a nonpartisan issue, reinforcing support for collaborative solutions between agriculture, food banks, and policymakers.
The Bridge is a section of the STM Daily News Blog meant for diversity, offering real news stories about bona fide community efforts to perpetuate a greater good. The purpose of The Bridge is to connect the divides that separate us, fostering understanding and empathy among different groups. By highlighting positive initiatives and inspirational actions, The Bridge aims to create a sense of unity and shared purpose. This section brings to light stories of individuals and organizations working tirelessly to promote inclusivity, equality, and mutual respect. Through these narratives, readers are encouraged to appreciate the richness of diverse perspectives and to participate actively in building stronger, more cohesive communities.
Rod: A creative force, blending words, images, and flavors. Blogger, writer, filmmaker, and photographer. Cooking enthusiast with a sci-fi vision. Passionate about his upcoming series and dedicated to TNC Network. Partnered with Rebecca Washington for a shared journey of love and art.
McDonald’s First Job Confessional Turns Career Stories Into Free Meal Opportunity
McDonald’s is launching First Job Confessional, a campaign inviting fans to share first job stories for a chance to receive a $15 gift card in select cities.
McDonald’s is Asking Fans to Get Real About Their First Job Skills in Exchange for Free Meals
First Job Confessional
McDonald’s is putting first jobs in the spotlight with a new campaign that asks fans to share the real-world skills they gained early in their working lives. Launched on National Employee Appreciation Day, the brand’s First Job Confessional invites people to reflect on how those first roles helped shape their careers — and, in some cases, earn a free meal in the process.
The campaign is built around a simple idea: first jobs often teach lasting skills that deserve more recognition. Whether someone learned problem-solving while babysitting, communication during a lunch rush, or teamwork behind a counter, McDonald’s is framing those experiences as valuable career foundations. The company says those are the same kinds of skills employers continue to prioritize as workplace demands evolve.
McDonald’s is Asking Fans to Get Real About Their First Job Skills in Exchange for Free Meals
How the First Job Confessional Works
In select cities, McDonald’s is setting up confessional booths designed to look like ordering kiosks. But instead of placing a meal order, participants can record a story about their first job and the skills they picked up along the way. Those who take part in person will have the opportunity to receive a $15 McDonald’s gift card, while supplies last.
Fans who cannot attend in person can still join online by posting their stories using #FirstJobConfessional. McDonald’s says selected videos may also be featured on its YouTube channel, extending the campaign beyond the live events.
The Bridge is a section of the STM Daily News Blog meant for diversity, offering real news stories about bona fide community efforts to perpetuate a greater good. The purpose of The Bridge is to connect the divides that separate us, fostering understanding and empathy among different groups. By highlighting positive initiatives and inspirational actions, The Bridge aims to create a sense of unity and shared purpose. This section brings to light stories of individuals and organizations working tirelessly to promote inclusivity, equality, and mutual respect. Through these narratives, readers are encouraged to appreciate the richness of diverse perspectives and to participate actively in building stronger, more cohesive communities.
Why Phoenix’s Skyline Has Stayed Low — And How It Compares to Los Angeles
Discover why Phoenix’s skyline lacks supertall skyscrapers, from FAA flight path limits near Phoenix Sky Harbor International Airport to how it compares with Los Angeles’s skyline growth.
Last Updated on March 25, 2026 by Daily News StaffTall buildings in downtown Phoenix Arizona
Phoenix is the fifth-largest city in the United States, yet its skyline doesn’t resemble other major metros like Los Angeles, Chicago, or Dallas. Despite rapid population and economic growth, downtown Phoenix has long lacked supertall skyscrapers — and until recently, didn’t even have a building tall enough to qualify as a true “skyscraper” under standard definitions.
The Basics: Phoenix’s Height Reality
The tallest structure in Phoenix for decades has been Chase Tower, rising to about 483 feet. Under the Council on Tall Buildings and Urban Habitat definition, a skyscraper reaches at least 492 feet — which means Phoenix has technically lacked one — despite its size and population.
Why doesn’t Phoenix have super tall skyscrapers? 🤔🌵 It’s not what you think… ✈️ From FAA flight paths over Phoenix Sky Harbor International Airport to the city’s sprawling growth, there’s a hidden reason the skyline stayed low for decades. But that might be changing… 👀🏙️ Phoenix Arizona CityFacts UrbanPlanning Skyline DidYouKnow Infrastructure RealEstate USCities #STMdailynews♬ original sound – STMDailyNews – STMDailyNews
A new project, the Astra Tower, is planned to rise around 540+ feet when it breaks ground, potentially giving Phoenix its first true skyscraper.
Airport Proximity: The FAA’s Height Grid
FAA Obstacle Evaluation & Downtown Limits
Phoenix’s skyline constraints are rooted in aviation safety.
📍 Phoenix Sky Harbor International Airport sits just a few miles from downtown.
The Federal Aviation Administration (FAA) regulates building heights near airports so they don’t obstruct flight paths, require planes to alter approaches, or interfere with climb-out safety.
In Phoenix, this results in a layered set of height limits that vary by location and elevation above sea level — often measured in feet above mean sea level (MSL) rather than simply building height from ground.
The city’s zoning code divides downtown into multiple contour zones with distinct maximum elevation values (e.g., 1,275 ft, 1,525 ft, 1,700 ft MSL), each tied to how close it sits under airport flight paths.
That means in some blocks you can’t build above a specific elevation even if ground levels are lower — a regulatory “roof” that varies across downtown.
City zoning also explicitly states that no building can exceed the FAA’s airport height limits, even if other bonuses or zoning allowances exist.
Phoenix vs. Los Angeles: A Quick Comparison
Los Angeles: Higher Limits, Different Constraints
Cities like Los Angeles also have nearby airports (e.g., Los Angeles International Airport), but their key business districts aren’t directly under major flight corridors.
LA’s downtown has:
Taller office and residential towers
A financial core with dense development
Fewer FAA-driven overlays because the flight paths stretch past the downtown edge
Los Angeles’s tallest buildings — including Wilshire Grand Center (~1,100 ft) and U.S. Bank Tower (~1,018 ft) — were built where FAA restrictions don’t force low ceilings. FAA evaluations were conducted but didn’t cut as deeply into downtown zoning compared to Phoenix.
Phoenix, by contrast, sits right under approach and departure corridors — leading to consistent FAA involvement in almost every proposed mid- or high-rise downtown.
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Economic and Planning Philosophies
Beyond FAA rules:
Phoenix developed in the automobile era, with vast inexpensive land encouraging horizontal growth.
Los Angeles grew earlier with heavier investment in centralized neighborhoods and higher density.
Phoenix’s village plan long encouraged multiple smaller hubs instead of concentrating all growth in one downtown core.
These historical differences mean Phoenix didn’t have the same economic “pressure” to build up — even with zoning that allows significant height if FAA permits are met.
What This Means for Phoenix’s Future
Phoenix still has room to grow vertically — but:
FAA height contours will remain the ceiling unless flight paths change
Developers must secure determinations of no hazard from the FAA before going taller
New projects like Astra show demand for taller buildings is rising
As Phoenix’s urban core densifies and land becomes scarcer, its skyline may yet reach higher — but always within the invisible grid drawn by aviation safety.
Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter. https://stmdailynews.com/the-knowledge/
