Friday, April 17, 2026

What Happens When Light Goes Boom? Part 3: Brad Bradington Sprints

The Advanced Test Reactor at Idaho National Laboratory — the blue glow is Cherenkov radiation from electrons outracing light in water. Argonne National Laboratory. CC BY-SA 2.0, via Wikimedia Commons.

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.



Small Trojan Asteroids Defy Expectations

Concept art of Lucy visiting a Trojan asteroid. Credit - NASA / Goddard Spaceflight Center / SwRI

Understanding the beginning of the solar system requires us to look at some very strange places. One such place is at the so-called “Trojan” asteroids that share Jupiter’s orbit in front of and behind it. But for a long time, these cosmic time capsules have held a mystery for astronomers: why are they color-coded? The populations of larger asteroids are very clear split into two distinct groups - the “reds” and the “less reds”, because apparently they’re all red to some extent. A new paper from researchers in Japan tried to solve this mystery by taking a close look at even smaller asteroids, and their findings, published in a recent edition of The Astronomical Journal, actually brings up a completely different question - why don’t smaller Trojan asteroids have the same color-coding?



Life Beyond Biosignatures: A New Method In The Search For Life

This artist's illustration shows what Mars might look like if it were terraformed. New research shows how the effects of terraforming, whether intentional or not, could help identify clusters of planets the are habitable and that life has spread to. Image Credit: Daein Ballard / CC BY-SA 3.0.

Researchers from the Earth-Life Science Institute (ELSI) and National Institute for Basic Biology have developed a new method to detect extraterrestrial life without relying on traditional biosignatures. By modelling how life might spread between planets, they demonstrate that life could be detected through statistical patterns across planetary populations rather than on individual planets. This "agnostic biosignature" approach could assist in guiding future searches for life beyond Earth.



To Survive Deep Space, Astronauts May Owe a Debt to Microscopic Worms

A fluorescing C. elegans worm. Credit - University of Exeter

Living long-term on the Moon means surviving the devastating toll that deep space takes on a human body. Astronauts in low gravity environments suffer muscle and bone loss, vision-altering fluid shifts, and heavy radiation exposure - all of which are incredibly hazardous to our biology. So, to help future lunar explorers survive, a new crew just arrived at the International Space Station (ISS). That might not sound surprising, except this crew is composed of worms.



Watch This Dark Volcanic Ash Creep Across the Red Planet

Picutre of the ash creeping across Utopia Planitia. Credit - ESA/DLR/FU Berlin

Mars is well known as a static, frozen desert. We tend to think of the only thing changing on the surface of the Red Planet is due to the occasional dust storm. But if you look closely - and are willing to wait decades - you’ll see the planet is very much alive - at least in the environmental sense. The European Space Agency just released some spectacular new images from the High Resolution Stereo Camera (HRSC) on its Mars Express Orbiter, one of which shows a surprisingly “fast” geological change happening in Utopia Planitia. A dark, ominous-looking blanket of volcanic ash is actively creeping across the bright red sands - and it's moving (relatively) fast.



Thursday, April 16, 2026

What Happens When Light Goes Boom? Part 2: The Crowd, the Molasses, and the Speed of Light (Sort Of)

James Clerk Maxwell, ca. 1870. Unknown author. Public domain, via Wikimedia Commons.

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.



Early Galaxies Were Surrounded by Huge Clouds of Hydrogen, and Astronomers Found a Whole Bunch!

This illustration depicts a gas halo surrounding a quasar in the early Universe. Credit: M. Kornmesser/ESO

Astronomers using data from the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) have discovered tens of thousands of gigantic hydrogen gas halos, called “Lyman-alpha nebulae,” surrounding galaxies 10 billion to 12 billion years ago.