Big Picture Science

The reign of Le Grand K has come to an end. After 130 years, this hunk of metal sitting in a Parisian vault will no longer define the kilogram. The new kilogram mass will be defined by Planck’s constant, joining three other units for redefinition by fundamental constants. But as we measure with increasing precision – from cesium atomic clocks to gravitational wave detectors able to measure spaceti...

Sexist snow plowing? Data that guide everything from snow removal schedules to heart research often fail to consider gender. In these cases, “reference man” stands in for “average human.”  Human bias also infects artificial intelligence, with speech recognition triggered only by male voices and facial recognition that can’t see black faces. We question the assumptions baked into these numbers and...

(repeat) Looking to boost your brainpower? Luckily, there are products promising to help. Smart drugs, neurofeedback exercises, and brain-training video games all promise to improve your gray matter’s performance. But it’s uncertain whether these products really work. Regulatory agencies have come down hard on some popular brain training companies for false advertising. But other brain games have...

Without sand, engineering would be stuck in the Middle Ages. Wooden houses would line mud-packed streets, and Silicon Valley would be, well, just a valley. Sand is the building material of modern cities, and we use more of this resource than any other except water and air. Now we’re running out of it.  Hear why the Roman recipe for making concrete was lost until the 19th century, and about the sup...

“Diversity or die” could be your new health mantra. Don’t boost your immune system, cultivate it! Like a garden, your body’s defenses benefit from species diversity. Find out why multiple strains of microbes, engaged in a delicate ballet with your T-cells, join internal fungi in combatting disease. Plus, global ecosystems also depend on the diversity of its tiniest members; so what happens when th...

(repeat) Are you ready to defer all your personal decision-making to machines? Polls show that most Americans are uneasy about the unchecked growth of artificial intelligence. The possible misuse of genetic engineering also makes us anxious. We all have a stake in the responsible development of science and technology, but fortunately, science fiction films can help. The movies Ex Machina and Juras...

(repeat) The Earth is not round. Technically, it’s an oblate spheroid. But for some people, the first statement is not even approximately correct. Flat Earthers believe that our planet resembles – not a slightly squashed grapefruit – but a thick pancake.  A journalist who covered a Flat Earth convention describes the rationale behind this ever-more popular belief.  So how do you establish science...

Crowded subway driving you crazy? Sick of the marathon-length grocery store line? Wish you had a hovercraft to float over traffic? If you are itching to hightail it to an isolated cabin in the woods, remember, we evolved to be together. Humans are not only social, we’re driven to care for one another, even those outside our immediate family.   We look at some of the reasons why this is so – from t...

If you bake, you can appreciate math’s transformative properties. Admiring the stackable potato chip is to admire a hyperbolic sheet. Find out why there’s no need to fear math - you just need to think outside the cuboid. Also, how nature’s geometric shapes inspire the next generation of squishy robots and an argument for radically overhauling math class. The end point of these common factors is ac...

(repeat) Heredity was once thought to be straightforward. Genes were passed in an immutable path from parents to you, and you were stuck – or blessed – with what you got. DNA didn’t change.  But now we know that’s not true.  Epigenetic factors, such as your environment and your lifestyle, control how your genes are expressed. Meanwhile, the powerful tool CRISPR allows us to tinker with the genes t...

Neil, Buzz, and Michael made it look effortless, but the moon landing was neither easy nor inevitable. Soon after President Kennedy publicly stated the goal of sending Americans to the moon, NASA confessed that the chances of success were only about 50/50.  But on July 20, 1969, despite enormous difficulties, astronauts stepped onto the lunar regolith. In this special anniversary episode, we go be...

Laughing rats, sorrowful elephants, joyful chimpanzees. The more carefully we observe, and the more we learn about animals, the closer their emotional lives appear to resemble our own. Most would agree that we should minimize the physical suffering of animals, but should we give equal consideration to their emotional stress? Bioethicist Peter Singer weighs in. Meanwhile, captivity that may be ethi...

(repeat) SMS isn’t the original instant messaging system. Plants can send chemical warnings through their leaves in a fraction of a second. And while we love being in the messaging loop – frenetically refreshing our browsers – we miss out on important conversations that no Twitter feed or inbox can capture. That’s because eavesdropping on the communications of non-human species requires the abilit...

(repeat) There’s evidence for a subsurface lake on Mars, and scientists are excitedly using the “h” word. Could the Red Planet be habitable, not billions of years ago, but today? While we wait – impatiently – for a confirmation of this result, we review the recipe for habitable alien worlds. For example, the moon Titan has liquid lakes on its surface. Could they be filled with Titanites? Dive into...

(repeat) Okay you animals, line up: stoned sloths, playful pandas, baleful bovines, and vile vultures. We’ve got you guys pegged, thanks to central casting.  Or do we? Our often simplistic view of animals ignores their remarkable adaptive abilities. Stumbly sloths are in fact remarkably agile and a vulture’s tricks for thermoregulation can’t be found in an outdoors store.  Our ignorance about some...

Poisonous snakes, lightning strikes, a rogue rock from space. There are plenty of scary things to fret about, but are we burning adrenaline on the right ones? Stepping into the bathtub is more dangerous than flying from a statistical point of view, but no one signs up for “fear of showering” classes.  Find out why we get tripped up by statistics, worry about the wrong things, and how the “intellig...

(repeat) The seas are rising.  It’s no longer a rarity to see kayakers paddling through downtown Miami. By century’s end, the oceans could be anywhere from 2 to 6 feet higher, threatening millions of people and property. But humans once knew how to adapt to rising waters. As high water threatens to drown our cities, can we learn do it again. Hear stories of threatened land: submerged Florida subur...

A new theory about life’s origins updates Darwin’s warm little pond. Scientists say they’ve created the building blocks of biology in steaming hot springs. Meanwhile, we visit a NASA lab where scientists simulate deep-sea vent chemistry to produce the type of environment that might spawn life. Which site is best suited for producing biology from chemistry? Find out how the conditions of the early...

The catastrophic explosion at the Chernobyl nuclear power plant in April 1986 triggered the full-scale destruction of the reactor. But now researchers with access to once-classified Soviet documents are challenging the official version of what happened both before and after the explosion. They say that the accident was worse than we thought and that a number of factors – from paranoia to poor engi...

(repeat) DNA is the gold standard of identification. Except when it’s not. In rare cases when a person has two complete sets of DNA, that person’s identity may be up in the air. Meanwhile, DNA ancestry tests are proving frustratingly vague: dishing up generalities about where you came from rather than anything specific. And decoding a genome is still relatively expensive and time-consuming.  So, w...

Your virtual assistant is not without a sense of humor. Its repertoire includes the classic story involving a chicken and a road. But will Alexa laugh at your jokes? Will she groan at your puns?  Telling jokes is one thing. Teaching a computer to recognize humor is another, because a clear definition of humor is lacking. But doing so is a step toward making more natural interactions with A.I.  Fin...

(repeat) Dinosaurs are once again stomping and snorting their way across the screen of your local movie theater. But these beefy beasts stole the show long before CGI brought them back in the Jurassic Park blockbusters. Dinosaurs had global dominance for the better part of 165 million years. Compare that with a measly 56 million years of primate activity. We bow to our evolutionary overlords in th...

DecodeHer They were pioneers in their fields, yet their names are scarcely known – because they didn’t have a Y chromosome. We examine the accomplishments of two women who pioneered code breaking and astronomy during the early years of the twentieth century and did so in the face of social opprobrium and a frequently hostile work environment. Henrietta Leavitt measured the brightnesses of thousand...

(repeat) There’s no place like “ome.” Your microbiome is highly influential in determining your health. But it’s not the only “ome” doing so. Your exposome – environmental exposure over a lifetime – also plays a role. Hear how scientists hope to calculate your entire exposome, from food to air pollution to water contamination. Plus, new research on the role that microbes play in the development of...

(repeat) Hundreds of thousands of scientists took to the streets during the March for Science. The divisive political climate has spurred some scientists to deeper political engagement – publicly challenging lawmakers and even running for office themselves.  But the scientist-slash-activist model itself is contested, even by some of their colleagues. Find out how science and politics have been his...