Objective: Discover how to use the evaporation of water to keep chocolate-covered candy from melting Areas of science: Chemistry Difficulty: Medium beginner Time required: ≤ 1 day Prerequisites: None Material availability: Readily available Cost: Very low (under $20) Safety: No issues Credits: Kelsey Woods, Cyberchase Intern; edited by Sandra Slutz, PhD, and Sabine De Brabandere, PhD, Science Buddies You’ve probably noticed that when you’re outside on a hot summer day, your body starts to sweat. But did you know that sweat, or perspiration, is actually your body’s way of cooling do ..read more

A new gel can sponge up dirty water. When the water later comes out, it emerges clean and fresh. The new material is a hydrogel, spongy tangles of threadlike molecules that stick to — and absorb — water. Like a string of beads, it’s made of large molecules called polymers that are strung together from repeating units. A plain old hydrogel sitting in dirty water would get scummy on the outside. Clean water would get dirty again when it flowed out of the gel. But the new hydrogel is self-cleaning. Explainer: What is a hydrogel? When dropped in polluted water, the gel absorbs the water. It blocks ..read more

Accretion disk, (noun, “Uh-kree-shun disk”) An accretion disk is a swirl of gas, dust and plasma orbiting a massive celestial object, such as a star or a black hole. These materials spiral inward like a whirlpool, attracted by the central object’s gravity. An accretion disk’s velocity increases as it draws nearer the disk’s center. Friction and gravitational forces from the central object cause the gas and dust to emit energy — lots of it. Studying that energy gives scientists clues about the object at the disk’s center. For example, accretion disks that form around black holes emit X-rays an ..read more

Shape-shifting liquid-metal robots might not be limited to science fiction anymore. Robots that melt and reform have appeared in movies like Terminator 2. Now, researchers have created a material that can similarly switch from solid to liquid and back. They used it to build mini machines. These can squeeze into tight spaces and do tasks, such as soldering a circuit board. Someday, the new material could give flexible robots the ability to shimmy through narrow passages. Researchers described the work January 25 in Matter. The inspiration to build shape-shifting devices came from ..read more

Magnetism (noun, “MAG-net-izm”) Magnetism is a force that can push or pull objects. It is one aspect of a fundamental force of nature called electromagnetism. Moving electric charges create magnetism. Take the negatively charged electrons in atoms. These electrons spin as they swarm around the centers of atoms, creating tiny magnetic fields. Inside most materials, electrons spin in different directions. So, their magnetism cancels out and the material is not magnetic. But in some materials, such as iron, electrons tend to spin the same way. The particles’ magnetism adds up, and the material i ..read more

Roman concrete has stood the test of time. Some ancient buildings still stand after millennia. For decades, researchers have been trying to re-create the recipe that made them last — with little success. Finally, with some detective work, scientists have figured what’s behind their lasting power. Concrete is a mix of cement, gravel, sand and water. Admir Masic is a chemist at the Massachusetts Institute of Technology in Cambridge. He was part of a team that was trying to figure out what technique the Romans used to mix those ingredients. The researchers suspected the key was something called ..read more

Given enough time, jumping beans will always find their way out of the sun. Jumping beans are not actual beans. They’re seed pods with twitchy moth larvae inside. And they hop around in a way that will — if the larvae inside live long enough — eventually land them in shade. Researchers shared that finding January 25 in Physical Review E. Left out in the sun, a jumping bean might overheat and die. So, when a bean finds itself in a sunny spot, the moth larva inside will twitch. This makes the bean jump a short distance. But if these moth larvae can’t see where they’re going, how do they reach sh ..read more

Like a high-tech hammer of Thor, a powerful laser can grab hold of a lightning bolt and reroute its path through the sky. Scientists have used lasers to wrangle electricity in the lab before. But researchers now offer the first proof that this can also work in real-world storms. Their tests took place on a Swiss mountaintop. Someday, they say, it could lead to better protection against lightning. The most common anti-lightning tech is the lightning rod: a metal pole rooted to the ground. Because metal conducts electricity, it lures in lightning that might otherwise strike nearby buildings or p ..read more

This is another in our new series identifying technologies and actions that can slow climate change, reduce its impacts or help communities cope with a rapidly changing world. It takes a lot of energy to keep buildings comfortably cool in hot parts of the world. Researchers hope to reduce that energy use with a new window coating. Unlike air conditioners and fans, it doesn’t need power to work. As it comes through windows, sunshine is a big source of heat in buildings, explains Tengfei Luo. He hopes to change that. Luo is an engineer at the University of Notre Dame in Indiana. His team has jus ..read more

If you ever happen to fall through a wormhole, you won’t be coming back. It will snap shut behind you. But on the way, you may have just enough time to send one last message home. That’s the finding of a new analysis. A wormhole is a tunnel in the fabric of space. It would link two points in the cosmos. Wormholes are just theoretical. That is, scientists think they could exist, but no one has ever seen one. If they do exist, wormholes could provide shortcuts to distant parts of the universe. Or they might serve as bridges to other universes. There even may be multiple types of w ..read more