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The phrase “no two snowflakes are alike” is actually scientifically accurate. Snow forms high in the atmosphere, and despite its uniform appearance, each snowflake is different based upon where and how it was formed. Although snowflakes are non-living, they grow and change from the time they are formed to the time they reach the ground. Listen to learn how snow is formed and why it exists in some places but not others.
Cells are used in research to make scientific discoveries. A certain set of cells are among the most widely used in biomedical research worldwide. These HeLa cells have been used to research almost every disease and have played an important role in many scientific breakthroughs including the development of the polio vaccine. The cells come from a woman named Henrietta Lacks who has been mentioned in more than 70,000 published scientific papers. Listen to hear more about how these cells are used and the issues of privacy with her family.
For such a small molecule, caffeine has long been a controversial substance. Throughout the day, the human body produces a molecule called adenosine that can induce feelings of fatigue. Caffeine is a molecule that reverses the effects of adenosine. This results in feelings of alertness. But the impacts of caffeine can be dangerous. Listen to hear what determines whether caffeine is beneficial or harmful, and how to prevent caffeine-related deaths.
Our bodies react differently to extreme heat depending on how much humidity is in the air. Heat index is a measure of how hot it feels outside, taking into account both air temperature and relative humidity. As the humidity rises, the heat index rises. In dry heat, our sweat quickly evaporates, which helps lower our internal temperature; but on a humid day, our sweat cannot fully evaporate as the air is already damp, and this prevents us from effectively cooling off. It also raises our risk of heat stroke and even death. To illustrate the science, this podcast considers the case of a man who was lost for three weeks in a remote desert in southern Utah and survived. Listen to hear more about dry versus wet heat and how it affects the human body.
Woolly mammoths were large, elephant-like creatures that lived tens of thousands of years ago, during the last great ice age. The thick, furry coat is one of several traits that gave woolly mammoths an advantage in a very cold environment. Today, the closest biological relative is the Asian elephant, which prefers warmer climates. Scientists were curious about the genetic variations between the woolly mammoth and the Asian elephant, and what might account for the differences between the two species. In this audio story, we hear from a scientist who studied the DNA from the extinct mammoth and compared it to its contemporary descendant. Listen to learn more about what researchers discovered.
The glaciers in the European Alps started melting rapidly in the 1860s. But that didn’t correspond with the warming of the European climate at the end of what is known as the Little Ice Age. That warming didn’t occur until the 1910s. To understand the causes of the glacial melt, scientists considered the possible impact of the Industrial Revolution, which began in the 1840s. The recent melting in the Rocky Mountains of America could be caused by the same reasons. Listen to this story to learn about the theory that dust and soot are contributing to how quickly glaciers are melting.
One of the biggest earthquakes ever recorded struck recently, with minimal damage, no tsunami and it barely made the news. That’s because there are two kinds of earthquakes. This earthquake happened when two tectonic plates moved past each other horizontally, while more damaging earthquakes are caused when one plate slips beneath another. This radio story explains the two types of earthquakes and how they are gradually redefining the boundaries of the tectonic plates.
It's easy for some people to imagine what it's like to be a doctor, lawyer, or teacher. However, the day-to-day life of a shellfish and wetland ecologist can be a little more difficult to understand. Discover what an ecologist does by hearing from Danielle Kreeger, the science director for a group that works to protect and improve the Delaware River and Bay. Listen to hear more about her career as an ecologist.
The apples we are used to seeing in the supermarket are the same basic size and shape and they have familiar flavor profiles. But there are more apple varieties than you might imagine. There's a whole world of biodiversity in apples, but these apples don’t make it to the supermarket. Listen to learn more about America’s history with apples and the apple Renaissance taking place today!
While humans need food and water to survive, plants are able to get their energy from the sun through a process known as photosynthesis. Engineers are now trying to replicate this process of converting sunshine to power through artificial photosynthesis. They are trying to create an artificial leaf. Listen to learn how these problem solvers are approaching the challenge step by step.
Earthquakes can have far-reaching consequences not just on homes but on the power infrastructure. A 2008 earthquake in Southwest China left officials and engineers monitoring the structural integrity of enormous hydroelectric dams built to generate power. A fear of flooding caused by a cracked dam led some to wonder if they had taken the strengths of the region, its rivers and irrigation systems, and turned them into a potential threat. Listen to learn how hydroelectric power systems impact places and people.
Discussion of carbon dioxide (CO2) emissions often occur at the national level. Nations promise to lower emissions and scientists look for alternative energy sources. But new software is providing data for this emission reduction discussion at a local level. The software allows people to have a view into their carbon emissions on the level of a city, neighborhood, block and even household. Listen to learn how scientists and local officials are working together to track and understand emissions at the local level.
Gravity keeps our feet on the ground, it creates a curveball, and it can also be used to find new planets. The star at the center of our solar system maintains life on Earth and its gravitational pull creates the orbit of planets. But our sun is just one of many stars in an ever expanding universe. Alpha Centauri is the closest star system to our solar system and new technology is allowing us to better understand our neighbor. Observations of Alpha Centauri date back to 1592, but it wasn’t until 2012 that astronomers in Chile were able to identify a planet orbiting one of the stars in Alpha Centauri because of its gravitational wobble. Listen to learn more about the properties and potential of this new planet.
Thomas Jefferson’s vegetable garden at Monticello contains over 300 varieties of more than 90 different plants, demonstrating the diversity of Earth’s ecosystem. The former President and founding father prided himself on his diversified and rare collection of plants. And he never failed to record his gardening achievements in his famed “garden book." Listen to learn more about the history of Jefferson’s garden and its current state following restoration.
Heirloom seeds are more than 50 years old and are not genetically modified. Jere Gettle, author of "The Heirloom Life Gardener," is particularly fascinated by heirloom seeds and he noticed they were being dropped by seed catalogs in the 1980s. The plants they produce are typically different from what we see in the grocery store. Listen to learn more about Gettle’s fight to bring heirloom plants back to our dinner tables.
It is difficult to conceptualize the magnitude of our solar system, but the journey of the Voyager spacecrafts can help. In September 1977 NASA launched the Voyager spacecrafts to gain information about the far off giant planets in our solar system. The spacecrafts and the project endured after studying Jupiter, Saturn, Uranus and Neptune and continued to travel away from earth and through our solar system. Thirty-five years after Voyager 1 left Earth, and over 11 billion miles away, it became the first man-made object to leave our solar system and enter interstellar space. Listen to learn what researchers have been researching from the edge of our solar system.
The Ebola outbreak in West Africa has inspired widespread fear throughout the U.S. and in many other countries. In reality, the threat of Ebola is actually quite small with only 1,700 deaths since 1976. The rarity of the Ebola virus has given major pharmaceutical companies very little incentive to develop a treatment for the virus given that the market for such a drug would be almost nonexistent. However, BioCryst Pharmaceuticals, a small pharmaceutical company based in Frederick, MD, has been given government help to develop a cure for the virus. Listen to learn more about the complexity of the Ebola virus and what is being done to develop a cure.
Tsunamis are created by tectonic plates thrusting against each other and then lifting the sea floor and dropping it down, which creates a giant wave. A 2010 earthquake in Chile was caused by a shift in the seafloor. This same shift set off tsunami detection buoys and left scientists waiting for the tsunami to hit. But it ended up being small. Listen to learn more about this quake and how tsunamis are created.
Food gives our body the energy needed to function and thrive. But what is energy? Where can you find it and how can you calculate it? This public radio story explores the energy in a cheese curl by burning it. Listen to learn about a great lab that allows you to calculate the energy in food.
As nations look for clean energy alternatives, many are turning to wind and solar, but Indonesia is turning to its volcanoes. Indonesia has 130 active volcanoes. These volcanoes generate geothermal heat that is released through vents and hot springs throughout the country. Power companies are learning to harness and redirect this heated steam into power plants in order to generate electricity. Indonesia’s geothermal energy potential is huge, but start up costs and oil subsidies might prevent this burgeoning clean energy from taking off.
As plants and animals reproduce over time, they are able to change and adapt to ensure or improve their chances of survival. The evolutionary goal of reproduction is paired with the concept of natural selection and survival of the fittest to determine who will reproduce. From colorful plumage to size, different species use different strategies to ensure reproduction and mate selection. The sand tiger shark has a unique strategy to ensure successful reproduction - and it depends on the timing of mating. Listen to learn more about the ultimate sibling rivalry while in the womb.
In 2014, astronomers discovered a new dwarf planet on the edge of our solar system. This discovery has changed scientists’ understanding of what exists in the solar system beyond the more well known dwarf planet, Pluto. The new planet is a pink ball of ice, and scientists believe there could be an unseen and undiscovered planet larger than Earth in the far reaches of our solar system.
Animals adapt to their environment in ways that protect them from predation and allow them to find prey. Electric eels look like water snakes but use electricity to hunt. New scientific studies have gained insight into how electric eels use different electric volts to find and kill their prey. Listen to learn how the eel’s hunting method is adapted to their environment.
Animal species evolve and adapt over time. This ability to change lays the groundwork for human evolution. Over 375 million years ago an important transition in this lineage occurred - animals living in the sea began living on land. This complex process happened gradually over generations and an unusual fish fossil found in the Canadian Arctic may help enhance our understanding of this progression.
Scientists say it’s nearly certain that human activity and fossil fuels are warming the planet. The mainstream discussion focuses on alternative energy and reducing fossil fuel emissions. But the field of geoengineering is looking for more large scale and proactive things we can do to offset warming. Some see this as an exciting way to help the planet, others as a threat. Listen to learn about the strategies geoengineers are exploring to prevent further global warming.
Scientists are using computer computations to link cases of extreme weather to global warming. Scientists set out to link major flooding in England and Wales in the fall of 2000 to climate change. This task was undertaken by scientists and citizens alike - running thousands of computer simulations and comparing the result in a world with climate change and one without it. Listen to learn what these simulations found.
To lower dependency on fossil fuels, some Americans have installed solar panels on their homes to produce their own clean energy. This decision involves a cost-benefit analysis of cost value and environmental impact. In some regions this cost-benefit ratio has been upset by fracking, and the cheap natural gas that it produces. How does supply and demand impact the cost of energy? How does the cost of energy impact people seeking alternatives such as solar energy? Listen to learn how one family has dealt is dealing with this shifting energy landscape.
The Grand Canyon has amazed visitors and scientist alike since it was discovered. The debate over what created this geologic wonder has been reignited in recent years. Is the Grand Canyon 6 million years old or 70 million? Listen to learn more about this debate between two geologists who have very opposing viewpoints.
Infectious diseases like plague don’t just impact humans, they can spread and decimate animal populations as well. One scientist saw the impact of plague in prairie dog colonies and among black footed ferrets. He questioned whether the scientific understanding of plague cycles and transmission was accurate. Listen to learn what scientists discovered about plague and its larger impact on ecosystems.
A United Nations report in 2014 shows that human activities are changing the planet. The scientists are more confident in their conclusions that humans are causing global warming. There are rising sea levels, higher temperatures and impacts on wildlife. This conversation with a public radio reporter looks at the long term trend in global temperatures and what humans can do to reverse the trend.
Throwing a curveball is one of the most difficult pitches in baseball. Bill Lee, a former pitcher for the Red Sox, explains how important it is to consider physics when trying to throw a curveball. Listen to learn how objects travel through space and how gravity affects a curveball.
The "cash for clunkers" program was a limited federal government program in the U.S. that gave people credits to trade in their old, gas guzzling, polluting cars for newer ones. The goal was to get older cars off the road to improve pollution. Because the “cash for clunkers” program did not allow the re-sale of old car engines, junkyards were forced to turn the cars into scrap metal. Listen to learn what this scrap metal can be turned into.
Toys play an important role in children's development. They are also important to animals, even elephants. This public radio story is about how artists designed and built toys of elephants that were based on animal behavior and their environment. You’ll be inside the zoo with the elephants, hearing their joy when playing with the new toys.
A new way of looking at live cells is revolutionizing our understanding of how molecular life works. However, it is how one scientist managed to complete his study despite facing World War II in Japan that makes his discovery so intriguing. By using an old machine gun, Shinya Inoue made a microscope that enabled him to start to see how a cell divides. Listen to learn how Inoue finished his microscope and why it is so important to the science community.
There is debate whether fish like the bluefin tuna are going to go extinct. Some argue that the decline in bluefin results from excessive fishing. However, longtime bluefin fishers like Eric Stewart disagree with this stance as he sees an increasing population of bluefin. Listen to hear from both sides, and how one bluefin tuna can swim across the entire ocean.
Scientists are creating bacteria batteries by using wastewater to generate electricity. The microbes from sewage can be harnessed to develop microbial fuel cells. The process could provide ways to provide energy in remote places for very little money. Listen to learn how scientists are developing this energy and what they are learning from it.
Manatees, the vegetarian aquatic mammals that inhabit the waters of Florida, depend on natural warm water springs to survive the winter. However, those warm water sources have diminished over the years due to an increase in development around the area. Listen to learn how local power plants are maintaining the warm water to try to help the manatees.
People lose weight when sleeping, and much of that weight loss comes from merely breathing. Through a process of matter being recycled along with sweating while sleeping, people lose weight. However, the atoms and molecules involved are so small that it is hard to believe they are so powerful in this process. Listen to learn how this cycle works.
As the ocean rises, some island nations might disappear and the coastlines change. This is critical for some island nations that are at risk of slipping under water as sea levels rise. Political, economic, and personal consequences are factors in how the climate problems in these nations are dealt with. Listen to learn what can be done to prevent these catastrophic changes in our geography.
Global warming is expected to increase summer temperatures making cities even hotter. As concrete and asphalt within cities retain heat, it can increase health risks. The sun mixes with city pollution to create ozone that can irritate people's lungs, especially if they have breathing problems such as asthma. Listen to learn how public health officials are trying to help those living in the hottest areas.