Nobel week: light-controlled brains, particles from outer space and mirror moleculesNEWS | 12 October 2026Breaking down this year’s Nobel Prize–winning science, from switching brain cells on and off with light to catching cosmic neutrinos in Antarctic ice to building mirror-image molecules. Plus, a 194-year-old tortoise’s DNA might hold the key to a longer life.
Rachel Feltman: Happy Monday, listeners! For Scientific American’s Science Quickly, I’m Rachel Feltman. You’re listening to our weekly science news roundup.
Some of the biggest stories in science last week were the announcement of the Nobel Prize awards in Chemistry, Physics, and Physiology or Medicine. So we’re going to focus on those groundbreaking research topics today—with a fun little animal story at the end to send us off, of course.
Let’s start with the prize for physiology or medicine, which was announced last Monday. This year’s award went to Karl Deisseroth at Stanford University, Peter Hegemann at Humboldt University of Berlin, and Georg Nagel at the University of Wurzburg in Germany. They were recognized for their discoveries around light-gated ion channels and optogenetics.
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Optogenetics allows scientists to switch individual brain cells on and off. Because neurons use electrical signals to communicate with one another, scientists realized almost a century ago that they could use electrical stimulation to activate brain cells. Optogenetics combines this idea with genetic engineering to allow for more targeted, less invasive, safer cell stimulation than used to be possible. After genetically modifying neurons to make proteins that react to light, researchers can control those cells with a flash of light instead of an electrode.
Hegemann and Nagel contributed to the field by studying a single-celled alga that swims toward light, which they found had to do with a particular protein that opened up pores in the cell membrane when exposed to light. Deisseroth took those findings and applied them to experiments in living mammals.
We spoke to him about his win last week. Here he is explaining the impact of his discovery:
Karl Deisseroth: You know, once you know what matters for function, you can ask: How can dysfunction be addressed? You know, are there cells that cause dysfunction? Are there cells that can counteract dysfunction in a precise way? And what we're doing now is—and many others as well—is we're seeing: how can we leverage this precision to find new treatments, new medications, new neuromodulator approaches that build on this foundation of causality?
You know, this brings an opportunity that might help me communicate more with the public and to share the excitement of science, how discovery happens, how unlikely things get nurtured and that it takes time and it takes risk but that the outcome can be amazing if we’re willing to take the time and the risk.
Feltman: Last Tuesday saw Francis Halzen from the University of Wisconsin–Madison secure a rare solo award in Physics for the discovery of high-energy neutrinos of extraterrestrial origin. Here to tell us more about his contributions to the field is Joseph Howlett, a senior reporter at Scientific American and our resident physics expert. Tell us about those neutrinos, Joe!
Joseph Howlett: So neutrinos are my personal favorite fundamental particle. Of the 17 that we know about, the neutrinos are the ones we know the least. And that's why they've netted five times the Nobel Prize in Physics now.
The main thing that makes neutrinos different from other particles is that they pass through regular matter almost all the time without interacting. So there's neutrinos coming from space, from faraway black holes where super violent things are happening, like supernova and accretion, and these send out these very high-energy neutrinos. They make it all the way to Earth, but almost all the time they pass right through. We never notice that they're here. They're actually passing through us all the time. Neutrinos from the sun go right through our bodies without interacting.
It's really hard to build a detector that can catch a neutrino. And Halzen had this super ambitious idea to do so at the South Pole. He spearheaded the IceCube Neutrino Observatory. They chose Antarctica because it's a place with a lot of ice, and ice is great because when a neutrino interacts with ice, the light shines right through. It can go right through the ice like it's not there, all the way to whatever cameras you've buried inside.
So that was Halzen's great idea was that the Earth built this natural detector for us, right? All we have to do is put the cameras there to capture the light. So they bored these mile-deep holes with hot water jets and then lowered these strings of expensive cameras into each of them.
They span like a cubic kilometer of ice. And when a neutrino passes through that ice, usually it goes right through, but very rarely it will interact with one of the water molecules and produce a shower of light. And because the cameras are there, they can capture that light and say where that neutrino came from and how much energy it has.
So for the first time, we're able to see these neutrinos from these very, very faraway galaxies.
And actually, IceCube was the first experiment to see neutrinos from outer space, from outside of our solar system with this super high energy. So we've learned a lot about the universe thanks to this one experiment. It's also heralded this new era that astronomers call multimessenger astronomy. Basically, we've been looking at the sky with telescopes for hundreds of years, right? Measuring the light from faraway galaxies, from stars, X-rays even from black holes. But neutrinos are a whole new thing. They're not light. We're able to see the universe through a different lens. And when you combine this with the light measurements from all the telescopes in space and across the world, and you combine them additionally with gravitational wave detectors, which are another new technology that's won a Nobel Prize recently, now we have these three lenses that together can look at the same faraway objects and teach us all kinds of new things about them.
The thing about the multimessenger era is that it's just beginning. IceCube's only been operating for 16 years, and it's got a lot of life left to live, so we're gonna continue to learn all kinds of new things about the universe thanks to neutrinos, especially combined with these other experiments measuring light and gravitational waves.
Feltman: Thanks for breaking that down for us, Joe.
Last but not least is the Nobel Prize in Chemistry, which this year honored Henri Kagan of Paris-Sud University and Kenso Soai of the Tokyo University of Science for their pioneering research on autocatalysis in asymmetric organic synthesis. Try saying that one five times fast!
Many molecules come in two versions that are mirror images of each other. They can’t be superimposed over one another, the same way you couldn’t lay your right and left hands on top of each other and get them to line up. That’s called chirality, which happens to be one of my favorite words. When chemists create chiral molecules in the lab, they typically end up with equal amounts of each version. But that's not ideal, because the proteins in your cells—and in the natural world in general—are made from only one of those mirror images. Kagan and Soai figured out how to create just one of those mirror images at a time.
We’ll wrap up today’s news roundup with a story about a very, very old tortoise. The oldest tortoise, in fact. And not just the oldest tortoise, but the oldest terrestrial animal known to man. His name? Jonathan.
Giant tortoises are known generally for their long lifespans, but at around 190 years old, Jonathan is at least a century older than seems to be standard for his kind. And yeah, he is definitely that old. Photographs have confirmed that he was fully mature when he was brought to the island of Saint Helena in 1882, which means he had to have been at least 50 at the time.
A study published last week in Science Advances aims to explain how Jonathan is still alive and kicking all these years later. Genetic analysis of the tortoise compared with four of his peers apparently revealed mutations associated with DNA repair, cancer, telomere maintenance, mitochondrial health, insulin regulation, and other pathways associated with aging.
The researchers also took a look at the methylation of Jonathan’s genome. Methylation is when a small chemical tag gets added to DNA, which generally serves to turn a gene off. One sign of aging is a process called methylation entropy, which is where random patterns of methylation start to become more common. In other words, your body gets worse at targeting the right genes to switch off, which makes it more likely that some important protein won’t get made the way it’s supposed to.
In Johnathan’s genome, methylation entropy was unusually low in gene regions associated with mitochondrial function, RNA processing, and genome repair. That could give scientists some clues about what genes to target if they want to increase lifespan for other animals.
Speaking of longevity: We’ll be back on Wednesday to talk about why there’s so much shoddy science in this very buzzy field of research.
Science Quickly is produced by me, Rachel Feltman, along with Fonda Mwangi, Allison Rodgers and Jeff DelViscio. This episode was edited by Alex Sugiura. Marielle Issa and Aaron Shattuck fact-check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up-to-date and in-depth science news.
For Scientific American, this is Rachel Feltman. Have a great week!Author: Alex Sugiura. Rachel Feltman. Alli Rodgers. Source
