Modern innovations have allowed rides to simultaneously become more extreme and safer

Several ingenious additions to roller coasters, such as extra wheels, magnetic brakes, and hydraulic system safety bars, have largely reduced discomfort and threats such as broken rides or ejected passengers.

Researchers are studying roller coasters to improve mental health treatments

Scary rides stimulate our fight-or-flight response while simultaneously releasing feel-good endorphins like dopamine, serotonin, and oxytocin. Once we realize we're in a safe space, we can enjoy the ride and even feel confident and relieved by the accomplishment of overcoming a fearful feat.

Why so many people love roller coasters even though they’re scary

When a threat arises, it triggers our bodies to go into fight-or-flight mode and prepare for danger. However, when no obvious threat to our safety is present, this natural high can become enjoyable. Some people are more likely to enjoy these thrills based on factors like individual brain chemistry or physical health.

The odds of getting seriously injured on a US roller coaster are one in 15.5 million rides taken

Understanding the mechanics of a ride can help explain why they are so safe. Lift hills, launches, and breaks are each crucial components of coasters and are designed to possess numerous safety features in case of any dysfunction.

The general theory of relativity defines gravity as the curvature of spacetime

The breakthrough that redefined Isaac Newton's picture of gravity came when Albert Einstein realized that freely falling is indistinguishable from weightlessness, leading him to the principle of equivalence between gravity and acceleration. His prediction that gravity bends light was confirmed in 1919 during a solar eclipse.

Uncertainties in measurements make finding gravity's Newtonian limit unclear

Although Newton's "universal" law is unreliable in strong gravitational fields when compared with the field equations of general relativity, it is still taught for its accuracy on everyday scales. However, gravity's effect on small scales is too weak to be measured reliably, its accuracy at atomic scales remains unknown.

The centrifugal force is associated with the feeling of being pushed outward when moving in a circle, but it is a fictitious force arising from objects' tendency to move in straight lines.

Observations of colliding neutron stars by the Laser Interferometer Gravitational-Wave Observatory in 2017 confirmed that gravity travels at the speed of light.

How water pressure affects the body

The extreme conditions of the deep sea include increasing amounts of pressure as explorers and organisms descend into its depths. The major danger for both fish and humans is the way pressure changes how body tissues absorb chemical molecules...

The underlying fabric of the universe—spacetime—changes shape in the presence of mass and energy, which affects measurements of space and time.

Longer-duration space missions may amplify astronaut motion sickness

NASA is using the Kraken, a 50-foot-long, 100-ton US Navy research device, to simulate space motion sickness and vertigo and test possible recovery strategies, including testing out different, specific head movements. The Kraken, located at Wright-Patterson Air Force Base near Dayton, Ohio, can rotate participants at exposures of up to 3G.

Microgravity environments reduce muscle mass and bone density

Muscles that assist with balance and resistance to gravity are not subjected to their usual workload on the International Space Station. See the type of exercises that astronauts must complete for roughly two hours daily, and learn why these movements are necessary to preserve astronauts' muscles, bones, and cardiovascular health.

Why we pay to be scared

Why do we love roller coasters? It’s not just the speed or height, it’s controlled fear. Your brain thinks you’re in danger, then rewards you with dopamine.

In a closed space, acceleration cannot be distinguished from gravity

Just as pressing into a door when in a car makes a turn resembles the feeling of being pushed from the side, Albert Einstein’s equivalence principle states that being in a gravitational field feels the same as when a floor accelerates up against you, as in a rocket.

You are more likely to be struck by lightning than injured on a roller coaster

The ASTM F24 Committee on Amusement Rides and Devices consists of consumer advocates, government officials, amusement park operators, ride manufacturers, and industry suppliers who work to establish a safety standard for the designs and modifications of roller coasters.

Eleven deaf men played a pivotal role in America's human spaceflight program

In the mid-20th century, 11 deaf men volunteered for a series of experiments that offered unprecedented insights into the effects of weightlessness on the human body. Most of the men had become deaf in early childhood as a result of spinal meningitis, a condition known to damage the vestibular system and make them less susceptible to motion sickness. For a decade, these men participated in extreme motion sickness situations, including living in a slowly spinning room, spending time in centrifuge pods designed to simulate hypergravity, and flying in parabolic flights sometimes referred to as the "Vomit Comet." (Some users may experience a paywall.)

Where you are located in a gravitational field affects how quickly you age

The closer something is to the center of a massive object, the greater the strength of the massive object's gravitational field as a result of space-time being depressed more severely. Time passes more slowly the deeper an object is in this gravitational depression, meaning objects in the universe naturally seek to age more slowly.

What is gravity made of?

Our world at very small scales is governed by quantum mechanics, in which forces and energy come in discrete packets. At large scales, our world is governed by gravity, which moves the planets and stars and can create waves in spacetime. To merge...

Why roller coaster loops are never circular

The beloved looped roller coaster rides used to be shapes as perfect circles and constructed with wood, resulting in wobbly machinery that gave people whiplash. After the invention of steel and further scientific understanding, Six Flags debuted The Great American Revolution—a modern, oval loop with steel that offered a safer and smoother experience.

Understanding time dilation

The faster you go, the slower time ticks for you. And the stronger the gravitational field acting on you, the slower time ticks for you. These phenomena – collectively called time dilation – were first explained by Albert Einstein’s theories of general and special relativity. In this 11-minute video, beloved astrophysicist Neil deGrasse Tyson explains them to comedian Chuck Nice.

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.

Understanding how gravity works at the quantum scale is physics's greatest challenge

While the theory of general relativity explains how gravity works and quantum mechanics explains interactions at the subatomic scale, the two frameworks contradict one another. Developing a model of gravity mediated by particles can help complete the Standard Model.

Through gravitational redshift, light loses energy as it leaves a massive object

Just as one becomes exhausted as they walk up a flight of stairs against gravity, light is predicted to lose energy as it travels out of a gravitational well created by an object warping spacetime. This is observable through a decrease in the frequency of light toward longer, redder wavelengths.

Falling into a black hole would stretch and shred your body beyond recognition

As you approach a black hole, you initially feel weightless. Eventually, the difference in gravity between your feet and head would create a powerful stretching force that overcomes the molecular bonds in your body and pulls you apart.

Scientists validated Albert Einstein's theory of gravity by measuring the apparent positions of stars via their starlight as it traveled near the sun on its way to Earth during a total solar eclipse.

Some online users believe gravity will 'switch off' for 7 seconds in August 2026

Conspiracy theorists believe NASA is preparing for the gravity blackout under a classified operation called "Project Anchor." They speculate that the purpose of the secret project is to test whether Earth can survive such an event. NASA has rejected the claim. Considering the physics of a gravity blackout, the outcome would likely be chaotic but not total destruction.

Massive objects can significantly bend light to produce gravitational lensing

The theory of general relativity posits that mass and energy bend space and slow down the passage of time. One consequence is that massive objects, such as black holes, curve spacetime to such an extent that light from background sources can loop around them, producing multiple images or ring-like patterns.

Prolonged space travel significantly impacts multiple human body systems

Astronauts can lose 20% of their muscle mass after two weeks and 10% of their bone mass after six months in space. Decreased sharpness of eyesight and changes in neural connectivity, brain structure and gut bacteria have also been observed.

What a railroad spike through the head taught science about the brain

In 1848, a railroad worker survived an accident that drove a 13-pound iron bar through his head. The injury changed his personality, and our understanding of the brain.

Within Einstein's picture of the universe, gravity is technically not a force because forces cause accelerations that deviate objects from their natural path, and moving solely due to gravity is natural.

Engineer explains VR at five levels of complexity

While its possible to grab a virtual reality headset and hop into an immersive world with little effort, a significant amount of technical and biological science has gone into creating the effect of a 3D world. This video breaks down the technology in five layers of increasing complexity.

Roller coasters can cost millions of dollars to make, but they often offer a substantial payoff

Over 6,000 roller coasters are in operation around the world as of 2025, with ongoing demand to build more each year. Despite being costly (some theme parks pay upwards of $50M for these rides), their financiers are able to justify the investment when considering the long-term value of a ride that sticks around for decades with daily streams of visitors.

LIGO can detect changes in spacetime one ten-thousandth the width of a proton

Gravity is the weakest of the fundamental forces in nature, meaning the length of objects only changes by minuscule amounts as gravitational waves ripple through space from distant, albeit massive, cosmic events. LIGO's sensitivity can measure an object shifting its position by one seven-hundred-trillionth of the width of a human hair.

Six Flags’ now defunct Green Lantern ride was known to many as a ‘pelvic nightmare’

The Defunctland YouTube channel focuses on telling the stories of extinct amusement rides and experiences, like the ambitious “Green Lantern” coaster that ran from 2011 to 2024. Critics, enthusiasts, and casual riders alike seemed to agree the ride was the worst at Six Flags due to its discomfort on the lower body.

Understanding why suction cups rely on Earth's atmosphere to work

When pressed against a surface, air is squeezed out of a sealed volume, causing the internal pressure to drop below the surrounding atmospheric pressure, and this imbalance creates the "sticking." For this reason, astronauts do not use suction cups or related technologies to stay on spacecraft during spacewalks.

Explore a visualization of curved spacetime under general relativity

While depictions involving bends in elastic fabrics are common to illustrate gravity, they are circular representations that rely on gravity in the real world to depict gravity in the model. The river model instead shows how bends in spacetime convert speed through time into speed through space, producing acceleration.

Gravitational waves—ripples in spacetime that result from the motion of objects—were detected a century after Albert Einstein predicted their existence upon developing his theory of gravity.

How neutron stars serve as laboratories for testing Einstein's theory of gravity

Data from a 16-year study of an orbiting pair of spinning neutron stars showed that measurements of gravitational wave energy and the bending of light around the system were consistent with predictions made by general relativity to an accuracy of at least 99.99% across seven tests. (Some readers may experience a paywall.)