Brain
Purple exists only in our brains
Most colors represent a single wavelength of light. But your brain invents purple to deal with wavelengths from opposite ends of the visible spectrum.
Featured Articles in this Issue
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Cover Story
Why are scientists suddenly interested in UFOs?
For decades, science mostly ignored UFOs. Then in 2015 Navy pilots started reporting them. The U.S. government enlisted scientists to investigate.
Explainer
Technically Fiction
Humans
A real-life vampire probably couldn’t survive on blood alone
Vampires often have human bodies. To survive on blood, they’d need to shed millions of years of evolution.
Profile
Space
This astronomer searches for alien chemistry and tech
At the SETI Institute, Chenoa Tremblay uses radio telescopes to look for molecules and emissions given off by alien technology.
Features
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What’s so noble about the Nobel Prize?
The Nobel Prize might be the one science prize you’ve heard about. But does it really recognize the most important science?
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Why are scientists suddenly interested in UFOs?
For decades, science mostly ignored UFOs. Then in 2015 Navy pilots started reporting them. The U.S. government enlisted scientists to investigate.
More Stories from the October 1, 2025 issue
- Earth
Earth farts may explain some spooky floating lights
The gases released by earthquakes might occasionally ignite, triggering ghostly lights sometimes witnessed in South Carolina.
- Tech
This squirrel-like robot has some serious hops
Salto the jumping robot has a claw-like gripper. Like a squirrel, it can adjust its movement to help it stay balanced to stick a landing on "branches."
- Animals
Sheep, llamas and goats fall for optical illusions too
These findings could help reveal when and why falling for optical illusions evolved in animals.
- Plants
A genetic trick leaves these stinky plants reeking of rotting flesh
This DNA tweak in plants harnesses the same molecule behind our bad breath and transforms it into something worse: the stink of rotting flesh or dung.
- Materials Science
This electric ‘slime’ might help injuries heal faster
Our bodies call in healing cells with an electrical signal. When stretched or squeezed, this gel makes electricity that could boost that alert.
- Math
Experiment: M&M’S geometry
The amount of candy in an M&M’S bag is never enough, but just how much is it? Let’s find out which geometric formula gives the best estimate.
- Brain
Brain cells that make you feel full also make you crave dessert
If you want a sweet treat when you feel full after a big meal, blame your brain. Tests in mice and people suggest that the same cells signal satiety and a hunger for sugar.
