Short Wave

Did Earth’s Water Come From Space?

Choose your fighter for the origin of water on Earth! Was it always here or did it come to this planet from somewhere else in space? And, either way, what does this mean for other water worlds in our galaxy? To find out, we talk with Michael Wong [https://carnegiescience.edu/dr-michael-l-wong], an astrobiologist and planetary scientist at Carnegie Science. He gets into scientists’ strongest candidates for the ways water could have come to our planet many, many years ago – including whether it could have been made here. Buckle up: This is a hot debate in astrobiology right now. If you enjoyed this episode, check out our Space Camp [https://www.npr.org/series/g-s1-3299/short-wave-space-camp] series and our episode on whether life started on the ocean floor [https://www.npr.org/2025/08/11/nx-s1-5495449/life-space-moon-ocean-hydrothermal-vents].. Interested in more space science and more unresolved hypotheses about how the universe came to be how it is today? Email us your question at shortwave@npr.org [shortwave@npr.org]. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave [http://plus.npr.org/shortwave]. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

The trouble of zero

What better time to contemplate the conundrum that is zero than the start of a new year? Zero is a fairly new concept in human history and even more recent as a number. It wasn't until around the 7th century that zero was used as a number. That's when it showed up in the records of Indian mathematicians. Since then, zero has, at times, been met with some fear — at one point the city of Florence, Italy banned the number. Today, scientists seek to understand how much humans truly comprehend zero — and why it seems to be different from other numbers. That's how we ended up talking to science writer Yasemin Saplakoglu [https://www.yaseminsaplakoglu.com/] in this encore episode about the neuroscience of this number that means nothing. Read more [https://www.quantamagazine.org/how-the-human-brain-contends-with-the-strangeness-of-zero-20241018/] of Yasemin's reporting on zero for Quanta Magazine. Plus, check out [https://www.npr.org/2024/01/03/1198909057/brain-struggles-big-numbers-neuroscience] our episode on why big numbers break our brains. Interested in more math episodes? Let us know what kind of stories you want to hear from us in 2026 by emailing shortwave@npr.org [shortwave@npr.org]! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave [http://plus.npr.org/shortwave]. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Science In 2025 Took A Hit. What Does It Mean?

Science in the United States took some big hits this year. The Trump Administration disrupted federal funding for all kinds of scientific pursuits. Administration officials say those changes were a step towards reinvigorating federal agencies like the National Institutes of Health. But many scientists disagree. NPR health and science correspondents Rob Stein [https://www.npr.org/people/146944972/rob-stein] and Katia Riddle [https://www.npr.org/people/1128948946/katia-riddle] chat with host Emily Kwong [https://www.npr.org/people/767284140/emily-kwong] about what these cuts could mean for the future of science. Interested in more stories on the future of science? Email us your question at shortwave@npr.org [shortwave@npr.org]. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave [http://plus.npr.org/shortwave]. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Climate Anxiety Is Altering Family Planning

Gen Z and younger millennials are generally the most climate literate generations. As an age cohort that started learning about climate change in school, they're worried about how to plan for their future jobs, houses and, yes, kids. With climate-related disasters and global warming likely to worsen, climate anxiety is giving way to reproductive anxiety. So, what do experts say about how to navigate the kid question? On this encore episode of Nature Quest, Short Wave speaks to Alessandra Ram [https://www.alessandraram.com/], a journalist covering climate [https://www.goodluckmedia.co/]change, who just had a kid. We get into the future she sees for her newborn daughter and ask, how do we raise the next generation in a way that's good for the planet? Here are the resources recommended by the experts we interviewed for this story: Action Tools and Community Resources * The High-Impact Climate Action Guide [https://jpydatnf1hz.typeform.com/to/pUIM6hoy?typeform-source=wecanfixit.substack.com] by Kimberly A. Nicholas * The Climate Mental Health Network [https://www.climatementalhealth.net/] and Climate Emotions Wheel [https://www.climatementalhealth.net/wheel] * The Climate Café® Hub  [https://www.climate.cafe/]- for finding a local group Books and Research Papers * Climate Anxiety and the Kid Question: Deciding Whether to Have Children in an Uncertain Future [https://www.ucpress.edu/books/climate-anxiety-and-the-kid-question/paper], by Jade S. Sasser * Parenting in a Changing Climate: Tools for cultivating resilience, taking action, and practicing hope in the face of climate change [https://bookshop.org/p/books/parenting-in-a-changing-climate-tools-for-cultivating-resilience-taking-action-and-practicing-hope-in-the-face-of-climate-change-elizabeth-bechard/17505251], by Elizabeth Bechard * Under the Sky We Make: How to Be Human in a Warming World [https://www.penguinrandomhouse.com/books/665274/under-the-sky-we-make-by-kimberly-nicholas-phd/], by Kimberly A. Nicholas * The role of high-socioeconomic-status people in locking in or rapidly reducing energy-driven greenhouse gas emissions [https://www.nature.com/articles/s41560-021-00900-y], Nielsen, K.S., Nicholas, K.A., Creutzig, F. et al.  Got a question about changes in your local environment? Send a voice memo to shortwave@npr.org [shortwave@npr.org] with your name, where you live and your question. You might make it into our next Nature Quest episode! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave [http://plus.npr.org/shortwave]. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Why Kratom Is At The Heart Of A Big Public Health Debate

Kratom and 7-OH products are available in many smoke shops. But earlier this year, the FDA recommended certain 7-OH products be scheduled alongside opioids. This isn’t the first time kratom has come under scrutiny. Nearly a decade ago, the DEA wanted to make certain active ingredients in kratom controlled substances. Meaning products would go from being widely available to highly restricted. After a massive wave of protest, the DEA decided not to move forward. Producer Rachel Carlson [https://www.npr.org/people/1112796909/rachel-carlson] joins host Emily Kwong [https://www.npr.org/people/767284140/emily-kwong] to talk about what could happen this time around, and what scientists know – and don’t know – about kratom and 7-OH.  Interested in more of the science behind drugs and supplements? Email us your question at shortwave@npr.org [shortwave@npr.org]. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave [http://plus.npr.org/shortwave]. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]