Take a deep breath. Even if the air looks clear, it is nearly certain that you will inhale millions of solid particles and liquid droplets. These ubiquitous specks of matter are known as aerosols, and they can be found in the air over oceans, deserts, mountains, forests, ice and every ecosystem in between.
Health Check: why do I get a headache when I haven’t had my coffee?
Oort clouds around other stars should be visible in the cosmic microwave background
For decades, scientists have theorized that beyond the edge of the Solar System, at a distance of up to 50,000 AU (0.79 ly) from the Sun, there lies a massive cloud of icy planetesimals known as the Oort Cloud. Named in honor of Dutch astronomer Jan Oort, this cloud is believed to be where long-term comets originate from. However, to date, no direct evidence has been provided to confirm the Oort Cloud’s existence.
Research Check: can sleeping too much lead to an early death?
Why the summer sound of noisy crickets is growing fainter
Designed to deceive: How gambling distorts reality and hooks your brain
To call gambling a “game of chance” evokes fun, random luck and a sense of collective engagement. These playful connotations may be part of why almost 80 percent of American adults gamble at some point in their lifetime. When I ask my psychology students why they think people gamble, the most frequent suggestions are for pleasure, money or the thrill.
Celebrating the 150th anniversary of helium’s discovery – why we need it more than ever
Watching helium gas lift balloons into the air is a lot of fun – or perhaps a tragedy if that balloon belonged to a small child who let it go. And, who hasn’t sipped the helium gas from a balloon and then quacked like Donald Duck? Although, that’s not the smartest thing to do since helium can displace the air in our lungs, or cause other problems with respiration.
Six Things About Opportunity's Recovery Efforts
NASA's Opportunity rover has been silent since June 10, when a planet-encircling dust storm cut off solar power for the nearly-15-year-old rover. Now that scientists think the global dust storm is "decaying" -- meaning more dust is falling out of the atmosphere than is being raised back into it -- skies might soon clear enough for the solar-powered rover to recharge and attempt to "phone home."
Hubble Paints Picture of the Evolving Universe
Astronomers using the ultraviolet vision of NASA’s Hubble Space Telescope have captured one of the largest panoramic views of the fire and fury of star birth in the distant universe. The field features approximately 15,000 galaxies, about 12,000 of which are forming stars. Hubble’s ultraviolet vision opens a new window on the evolving universe, tracking the birth of stars over the last 11 billion years back to the cosmos’ busiest star-forming period, which happened about 3 billion years after the big bang.
What are rare earths, crucial elements in modern technology? 4 questions answered
Watch This Lifelike Robot Fish Swim Through the Ocean
Hothouse Earth: our planet has been here before – here’s what it looked like
Even if carbon emissions are reduced to hold temperature rises at the 2°C guardrail of the Paris Agreement, changes already afoot in the environment such as melting permafrost and forest die-back could accelerate warming well into the future, potentially pushing our planet into what is being called a “Hothouse Earth” state.
Frontal lobe paradox: where people have brain damage but don’t know it
Ageing in human cells successfully reversed in the lab
As the Martian dust storm subsides, there’s still no word from opportunity
Martian dust storms are a pretty common occurrence, and generally happen whenever the southern hemisphere is experiencing summer. Though they can begin quite suddenly, these storms typically stay contained to a local area and last only about a few weeks. However, on occasion, Martian dust storms can grow to become global phenomena, covering the entire planet.
Trees are made of human breath
Outside my office window, two skilled workers complete a hard and dirty job. They’re cutting the felled trunk of a tree into small enough pieces to be thrown into the back of a truck with the rest of the chipped remains. I know that this act was ultimately for my own safety. I, like tens of thousands of others over the past 50 years, regularly walked beneath the canopy of that tree.