Universe Today
Interstellar Comet 3I/ATLAS Left a Trail of Methane in its Wake
A new analysis of data obtained by JWST on 3I/ATLAS as it was on its way out of the Solar System (in December 2025) showed that its interior is rich in methane ice.
Physics
The physics of the universe
Recent Articles
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The Most Energetic Neutrino Ever Detected Could Be Primordial
Neutrinos are very difficult to detect. And when they are detected, pinpointing their sources is likewise difficult. New research shows that the most energetic neutrino ever detected must have had an extraordinarly energetic source. It could even be primordial.
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What Happens When Light Goes Boom? Part 4: What Brad Bradington Is Good For
Cherenkov radiation isn't just a beautiful phenomenon. It turns up in nuclear reactors, in the upper atmosphere, in gamma ray telescopes on three continents, in a cubic kilometer of Antarctic ice, and in hospital imaging suites. Here's what a light boom is actually good for.
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What Happens When Light Goes Boom? Part 3: Brad Bradington Sprints
We have the crowd. We have the star. Now it's time to put them together. Here's exactly what happens — and why — when a charged particle outruns the local speed of light in a material. Also: why it's always blue.
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What Happens When Light Goes Boom? Part 2: The Crowd, the Molasses, and the Speed of Light (Sort Of)
Before Brad Bradington can sprint down the red carpet, we need to understand the crowd. Specifically, we need to understand why a crowd of atoms and molecules slows down light — and why that creates a loophole that changes everything.
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What Happens When Light Goes Boom? Part 1: The Scientist Who Stared at a Glow
In 1934, a Soviet physicist named Pavel Cherenkov shone gamma rays into a bottle of water and noticed a faint blue glow. So had others before him. They all shrugged and moved on. Cherenkov didn't. What he found — by refusing to dismiss something he didn't understand — turned into one of the most useful phenomena in modern physics.
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Are Neutrinos Their Own Evil Twins? Part 4: Majorana's Mystery
In 1937, Ettore Majorana asked a question nobody else was even thinking about: does a particle have to have a distinct antiparticle? For neutrinos — which carry no charge — the answer might be no. They might be their own antiparticles. Deep underground right now, experiments are watching atoms decay, waiting for the signal that would prove it. So far: nothing. But the case is not closed.
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The Incredible Shrinking Neutrino.
They are the most abundant particles in the universe, yet we barely know they exist. Neutrinos stream through everything, through walls, through planets and even through you…. in their billions every second, leaving no trace. We've known for decades that they have mass, but pinning down exactly how much has defeated physicists for years. Now, the most sensitive experiment ever built has pushed our knowledge to a new frontier, and what it found raises a profound question about why these ghostly particles are so extraordinarily light.
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Are Neutrinos Their Own Evil Twins? Part 3: Dirac's Direct Solution
Neutrinos have mass — yet they never flip between left- and right-handed states the way every other massive particle does. The most logical fix is Paul Dirac's: invisible right-handed neutrinos that interact with nothing whatsoever. The math works. It even produces a beautiful explanation for why neutrino masses are so absurdly tiny. But it requires believing in particles that are permanently, in-principle undetectable.
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Are Neutrinos Their Own Evil Twins? Part 2: The Weak Left-Hander
The weak nuclear force is the eccentric cousin of the four forces — the one that only shakes hands with left-handed particles. That bizarre preference turns out to be absolutely critical for stars, nuclear fusion, and the existence of most matter. And neutrinos love it. There's just one problem: neutrinos appear to only exist in one handedness, which makes no sense at all.
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Are Neutrinos Their Own Evil Twins? Part 1: So We're Going to Redefine "Particle"
A brilliant physicist vanished in 1938, leaving behind one strange, quiet paper. It described something that shouldn't exist: a particle that is its own antiparticle. To understand why that matters, we first need to rethink what a particle even is — and that means getting weird with chirality, the Higgs field, and the neutrino's stubborn refusal to follow the rules.
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SuperCDM Experiment Reaches Critical Temperature, Bringing it One Step Closer to Detecting Dark Matter
The Super Cryogenic Dark Matter Search (SuperCDMS) experiment has reached its coldest operating temperature, hundreds of times colder than outer space.
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Jupiter's Lightning Could Be Almost Unbelievably Powerful
Juno observations show that Jupiter's lightning, already known to be powerful, is far more energetic than thought. Lightning triggered by a stealth superstorm in 2021-22 could be up to one million times more powerful than terrestrial lightning.
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The Crab Pulsar's Puzzling Emissions Finally Explained.
Pulsars are rapidly rotating neutron stars. The Crab Pulsar, an often studied supernova remnant, is known for its unusual radio emission patterns. New researchs says it's because of a "tug-of-war" between magnetism and gravity. Gravity acts as a focusing lens and plasma in the magnetosphere acts as a defocusing lens.
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CERN Adds a New Particle to Large Hadron Collider's Subatomic Zoo
Scientists at Europe's CERN research center say the Large Hadron Collider's LHCb experiment has discovered a "doubly charmed" particle that's like a proton, but four times as weighty.
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Is the Universe Defective? Part 4: Hiding in Plain Darkness
The WHAT? Yeah, the vortons. It’s not an anime monster-hunting show. It’s not some AI startup company. It’s a…it’s a thing. I think.
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Is the Universe Defective? Part 3: The Great Vanishing Act
And yeah, we have a problem.
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Is the Universe Defective? Part 2: The Persistence of Memory
But here’s the thing about these defects. They can’t just go away. They’re stuck.
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Is the Universe Defective? Part 1: The Good Old Days
Every time you flip a light switch, or check the time, or feel the sodium ions wiggling in your brain — don’t think about that one too much—you’re assuming something fundamental. You’re assuming the universe is a finished product. A completed work. You think the Big Bang happened, the forces of nature settled into their seats, and we’ve been cruising on a smooth, predictable ride ever since.
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Hunting Cosmic Ghosts from the Edge of Space
After five years of development and a nail biting launch from Antarctica, the PUEO experiment has completed a 23 day balloon flight at the edge of space, hunting for some of the most energetic particles in the universe. The instrument flew at 120,000 feet above Antarctica, using the entire continent as a detector to search for ultra high energy neutrinos, elusive particles that could reveal secrets about the universe’s most violent events. Now safely back on the ice with 50-60 terabytes of data, scientists are preparing to search through the results to see if they’ve caught these messengers from distant galaxies.