Black holes are absolutely silent, as they are creatures of pure gravity. But while black holes produce no sound of their own, they can generate sound waves in their environment. A Simple Black Hole Black holes are surprisingly simple objects. In the general theory of relativity, which is the framework we use to understand all things gravity, you only need three numbers to completely and totally describe a black hole: its mass, its spin and its charge. Seriously, that’s it. If you encounter an ...read more

Everyone — myself included — wants their cat to live forever. But it’s important to remember that as the years pile up, so does the likelihood of your feline friend developing age-related health issues. Among the most perplexing of these issues is cat dementia, also called feline cognitive dysfunction. Can Cats Get Dementia? Gary Landsberg, a veterinary behaviorist based in Ontario, has seen his fair share of it over the past few decades. He describes it as a progressive neurodegenerative ...read more

It is no secret that exercise can do wonders for our health. Exercise is good for losing weight, preventing illnesses, improving heart health and boosting well-being. Also, let’s be honest – if you are a workout buff, you know how good exercising feels. There is plenty of research to support these claims. Still, the benefits of exercising go beyond the physiological effects. Not surprisingly, it also impacts our neurobiology. As a machine working around the clock, the brain bears the brunt ...read more

With nothing more than an internet connection, you can improve your sleep, reduce anxiety, and … supposedly "enter the fourth dimension" (according to this video). Such are the bold promises of binaural beats, a kind of auditory illusion or digital drug that, some advocates say, can produce psychoactive effects resembling everything from ayahuasca to cocaine. While watching the above video, one commenter reported visiting a world “with trees that had crystals and seashells for leaves.” To ...read more

Smartphones are in pockets, purses and, for some people, under their pillows at night. Most Americans have a smartphone. About 95 percent of teenagers and people under 50 say they have one. For many people, smartphones are a convenience. But for phone addicts, they can feel like an obsession. There are apps to look at, games to play and websites to browse. One in five U.S. teens, for example, say they use YouTube “almost constantly,” and more than half say it would be difficult to stop ...read more

As life was first struggling to set foot on land in the Late Devonian Period, there was a predator waiting to snatch it back to the depths: the recently discovered Hyneria udlezinye, a toothy prehistoric fish estimated to have reached up to 9 feet long. It represents the largest monster fish yet uncovered from this period and appears to have lurked in the brackish waters of the modern-day Waterloo Farm site in South Africa, in wait for its prey. An excavation exposed a wall of fossils there in 2 ...read more

Atoms touch all the time! But to understand why we first have to decide what we mean by the word “touch.” Our normal conception of touching is grounded in the macroscopic world. I put a cup on the table – the cup is touching the table. You dip your toes in the water – you are touching the water, and so on. In all these cases, one solid boundary or surface (the bottom of the cup, the edge of your toe) touches another solid boundary or surface (the top of the table, the surface of the ocea ...read more

Stars are among the most identifiable objects in the sky. They light up the darkness and dot the galaxy. Stars are born within a dusty cloud and eventually form a mass of gas and chemicals that burns brightly in the sky. But ultimately, all stars, no matter how big and bright, must also die.  How Long Do Stars Live? The sun, for example, is a 4.5 billion-year-old star that will continue its lifespan for another 10 billion years. The sun lights up through a combination of hydrogen and helium in ...read more

Animals use camouflage to avoid detection. Some do it to avoid predators, while it allows others closer access to prey. Color plays a role in several different ways, including helping animals fade into natural surroundings, causing confusion with their colored patterns  and even altering their color. Camouflaged Animals When animals change colors, it’s done by pigments containing cells called chromatophores, located in their organs and skin. Let’s take a look at the methods of camouflage f ...read more

The scent of death revealed the location of the grisly, cannibalistic end to a hopeful trip to California nearly 175 years ago. This is thanks to cadaver-sniffing dogs who seem to have proven the ability to detect death thousands of years after some burials at historic sites. The Donner Party was a group of pioneers that attempted to migrate from Illinois to California in search of opportunity via a wagon train that partly followed the Oregon Trail starting in the spring of 1846. Tragically, the ...read more