Airports at high elevations, like Denver International Airport, have longer runways than most airports because airplanes cannot take off or land as quickly in thinner air.

Airplanes generate enough lift to fly by accelerating air faster over their moving wings, which makes the pressure above the wings lower than the pressure below.

Denver International Airport is associated with numerous dark conspiracy theories

Since opening in 1995, the country's largest airport has spurred a variety of conspiracy theories. Some believe the runways form a hate symbol; others believe its giant horse statue is cursed.

High-altitude kites can perform airborne collection of energy from high-speed winds

Winds at high altitude are stronger and more consistent than those near Earth's surface, where natural and artificial barriers disrupt airflow. Kites pulled by the wind can extend a tether like a yo-yo, creating electricity in an attached ground generator.

Why Japan builds airports on water

Some of Japan's roughly 100 airports are built on water—that is, engineers have created new land in bodies of water specifically to construct airports. This six-minute video explains why the country is doing so despite the higher cost of such airports.

In 2024, US airports generated over $1B of revenue—partly due to overpriced airport food

Some in the airport industry argue that charging street prices in airport restaurants isn't sustainable because it's more expensive to run a business inside an airport.

The informal boundary between the Earth and outer space lies within the atmosphere

Located approximately 100 kilometers (62.1 miles) above Earth's surface, the Kármán line serves as the approximate location where air density is too low to support aerodynamic lift to keep an aircraft airborne. Beyond this height, thrust is needed to propel objects through the air.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

Differences in pressure and temperature between atmospheric gases create wind

Because Earth's surface is not uniformly heated by the sun at all times, pockets of warmer and cooler air will form and interact. Warmer pockets of less dense air will rise, leaving gaps for cooler, denser air to move in. Wind is this movement of air from high-pressure to low-pressure areas.

Jet fuel is expensive—which is one reason why it's tough to make an airline profitable

Jet fuel is typically a commercial airline's second-largest expense, second only to labor. Oil prices can be volatile—there have been recent significant increases in jet fuel prices given the 2026 Iran conflict, for instance.

Turbulence is needed to make airplanes more stable and golf balls fly farther

Vortex generators—small fins placed along airplane wings—create small eddies that prevent airflow separation, maintaining lift and preventing stalls. Golf balls have dimples that create a turbulent boundary layer on their surface, minimizing drag forces.

Nearly 3 million people fly in and out of US airports every day—but not all of those passengers generate revenue for the airlines they purchase their tickets from.

Many airports have dedicated stores for luggage, despite most passengers having luggage with them already

This podcast episode argues that airport luggage stores exist due, in part, to the security measures implemented after 9/11, creating capitve audiences of travelers. Some argue that airport luggage store shoppers coming from places where luggage is more expensive could be purchasing luggage in international airports. Specifically, the episode traces airport history from the very beginning to today's luggage store in your local Terminal B.

Satellites in low Earth orbit can experience changes in their orbits due to shifts in solar activity, which alter the amount of energy Earth's atmosphere receives and its resulting density.

The turbulence experienced in airplanes results from unexpected changes in airflow

Pilots rely on forecasts, onboard tools, and air traffic control to avoid regions of severe turbulence during flight. Turbulence is generally weaker for those sitting in the front of the main cabin and for morning flights that follow cooler nighttime temperatures.

Why the edge of Earth's atmosphere varies depending on which property is considered

As the distance from Earth's center increases, the planet's gravitational force weakens, causing it to gradually lose its ability to retain gases at the farthest edge of its atmosphere—the exosphere. At a height of approximately 200,000 kilometers (124,000 miles)—halfway to the Moon—the exosphere has so little density that it is indistinguishable from interstellar space.

Commercial air travel's early days: Flights were short, cold, depressurized, and generally comfortable

After World War II, airlines competed for their high-end passengers by offering cocktails, meals, and plush seats, cultivating the image of the elite "Jet Set." By the 1960s, air transport was completely changing global trade and offering big profits to companies able to ship via plane.

A breakdown of Earth's atmospheric layers, including why it can get colder or hotter with altitude

Gases in the troposphere—the atmosphere's lowest layer—cool with increasing height as they get farther from the thermal energy emitted by Earth's warm surface. In the next layer—the stratosphere—ozone is increasingly heated by the sun's ultraviolet radiation with height. Because cooler air sinks and hotter air rises, the cooler troposphere and hotter stratosphere form a natural boundary keeping Earth's weather in the lowest layer.

Many budget airlines rely on baggage charges and other extra fees to make money.

The drastically different seat tiers on airplanes are a prime example of 'price segmentation,' which is key to keeping airlines profitable.

During flights, cell phones can act like signal jammers as they search for service

When farther from cell towers, these devices expend more energy to emit more powerful signals, which can overwhelm any ground-based tower or radio telescope they fly past. Rather than protecting the flight, airplane mode conserves a cell phone's battery.

Two main types of inflight WiFi connections are air-to-ground and satellite-based

ATG systems rely on aircraft antennae to catch signals from cellphone towers, while the latter uses a network of satellites transmitting data from space. As of 2022, airlines like Delta and United hosted over 1.5 million monthly WiFi sessions.

Some airlines—like American Airlines, which started the first modern airline loyalty program—have loyalty programs with higher valuations than the airline itself.

How endurance athletes can build resilience

Long-distance runners and other endurance athletes can improve their performances using tips explored in this article. Findings from two recent studies show that strength training, high-altitude training, and intense interval sessions are all potential methods for ameliorating long-term athletic capabilities.

Space tourism rockets emit up to 100 times more CO₂ per passenger than airplanes

Rocket launches release significant amounts of water vapor, nitrous oxide, and rocket propellants, which generate greenhouse gases and air pollutants. High-altitude emissions can persist for years, affecting the ozone layer.

Lightning storms are more common in coastal and tropical regions

Water-abundant areas that receive increased solar radiation, such as those near the equator, experience increased rates of evaporation, which produce tall clouds as moisture rises, cools, and condenses. Mountain ranges can also steer air to higher altitudes, creating collisions between atmospheric particles that generate charge imbalances—the precursors to lightning.

Find out how airlines quietly became banks

Some experts suggest airlines lose money on every flight. This video dives into how airlines have leveraged their loyalty programs to make billions of dollars, effectively evolving into banks.

Ingenuity and advanced engineering have allowed trains to overcome extreme landscapes

The Jungfrau Railway utilizes electric trains powered by hydroelectric energy to ascend the Swiss Alps, while Poland's Elbląg Canal hauls ships along cable-powered tracks driven by waterwheels. Germany's Wuppertal monorail navigates bends as it glides over a river valley, and New Mexico's Holloman High-Speed Test Track can achieve speeds of Mach 8.6 for rocket sleds.

How jet streams, which reside in the troposphere, shape and confine pockets of atmospheric air

These fast-flowing ribbons of air are hundreds of kilometers wide and typically travel from west to east due to Earth's rotation, with the polar front and subtropical jets serving as major drivers of global circulation. Warmer air near the equator pushes the polar front jets toward the poles, which can buckle and deform them as they contain frigid polar vortex systems.

According to the equivalence principle, objects in a closed space cannot tell the difference between whether they are accelerating or experiencing a uniform gravitational field.

Avalanches, which kill an average of 27 people in the US each year, typically require mountain slopes between 30 and 45 degrees and a layer of sturdy snow atop a weak, unstable layer, which can be put into motion by a trigger.

Hurricanes spin due to differences in air and ground speed as they move across Earth

The movement of an object across latitudes causes it to take a curved trajectory because its speed no longer matches that of the ground beneath it. This phenomenon, called the Coriolis effect, explains why hurricanes spin counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

The Wright Flyer was an engineering breakthrough, and modern aircraft still use the same principles of flight.

Gravity assists are crucial for space travel beyond Mars

By traveling near a moving celestial object, a passing object can gain or lose speed and change direction due to the acceleration provided by their mutual gravity. Some missions are planned around spacecraft performing multiple assists, or slingshots, to reduce fuel requirements for long-distance travel.

Winter Olympic sports highlight various laws and principles of physics

Figure skaters leverage the conservation of angular momentum during spins by tightening their bodies, and the skintight suits used in ski jumping help reduce drag. Centripetal force allows speedskaters to make tight turns, while friction on skis helps ski mountaineers climb slopes. No action can violate the conservation of energy.

Hurricanes, which rely on air consistently spinning in the same direction, cannot cross the equator because air curves in opposite directions north and south of it.

Six stories of survivors who fell from the sky

Rarely are there survivors when airplanes explode in air or crash due to the extreme speeds and elevation of the craft. Sometimes, though, people survive. Here are six stories of people who defied the odds and lived after falling from a plane.

Why Water Towers Are Built This Way

Most commercial planes get struck by lightning multiple times a year

This piece explains why commercial aircraft rarely crash in thunderstorms, detailing how pilots use onboard radar, shared reports, and strict avoidance protocols to navigate storms that look far more dangerous on screen than in reality.

Explaining why Earth's atmosphere doesn't crush us, despite weighing 11.24 quintillion pounds

Gravity pulling down on over 5.1 quintillion kilograms of gases surrounding Earth's surface produces an atmospheric pressure of 15 pounds per square inch (101,325 Newtons per square meter). However, since air surrounds objects, the forces from opposing air pressures normally cancel each other out, eliminating any detectable weight.

When modeling the fastest way to board passengers onto an airplane, research shows that random boarding is often faster than boarding in groups.

Explosive volcanic eruptions happen when magma pressure overcomes rock strength

Magma usually stays underground because of a balance between its upward pressure, the weight of the Earth’s crust above, and the crust’s rock strength. Landslides can reduce crust weight, while built-up gas pressure can strengthen magmastatic pressure.

Engineering tall structures requires managing wind, earthquakes, and other destabilizing factors

Reinforced concrete, energy dampers, braced frames, flexible structures, and aerodynamic decks were among the methods implemented when building structures such as the Shanghai Tower, the Texas Super Skyscraper, and the South Rangitīkei Viaduct.

The engineers proposing massive airbags for airplanes

Though they are famously rare, airplane crashes are some of the most shocking catastrophes when they occur. These researchers are dreaming up an implausible safety feature to help crashing planes land safely.

Learn about the bodies that govern the US commercial airline industry, such as the FAA

The Federal Aviation Administration (FAA) regulates US air travel, monitoring both safety and advancement. But despite deregulation in the 1970s, the industry has other governing bodies, too, including the US Department of Transportation and the TSA.

'Breather holes' in airplane windows help manage cabin pressure

Airplane windows have three layers of acrylic: the super durable outside layer, the inner pane which acts like a "scratch" surface, and the middle pane with the tiny hole. This bleed hole allows pressurized cabin air to be borne by the strong outer pane while preventing the inner pane from breaking.

Explore a timeline of advancements in American aviation

From the Wright brothers' flight of the first powered plane in 1903 near Kitty Hawk, North Carolina, to SpaceX's debut of the Falcon 9 rocket in 2010 with reusable boosters, this interactive shows off the technological evolution of flight, from mechanical propulsion to ballistic spaceflight. (Some users may experience a paywall.)

How reusable rocket boosters work

Reusable rockets drastically reduce the costs of space travel, saving agencies and companies millions of dollars by preserving expensive, complex boosters and their engines. The advancement required engineers to develop systems that restarted a booster in mid-flight to slow it down before landing.

Hail forms in freezing temperatures thousands of feet above the ground

Even if surface temperatures are well above freezing during the summer, updrafts during thunderstorms can push raindrops high into the atmosphere, where they can freeze and form hail. Giant hailstones the size of softballs require updrafts of close to 100 mph.

Simulations suggest that a paper airplane launched from the International Space Station would maintain its orientation and gradually descend for 3.5 days before chaotically tumbling down and burning up.

Farm animals help maintain the grounds at Chicago's O'Hare International Airport

Since 2013, a herd of goats, sheep, and a donkey have grazed on the scrub vegetation at the airport. In the process, they also help keep out animals that can be dangerous for pilots, like coyotes.