If a sheet of standard printer paper could be folded 42 times, it would have the same thickness as the distance from the Earth to the moon.

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.

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.

Watch what would happen if you literally had all the money in the world.

Why time ticks faster on the moon, which may need its own time zone

Because Earth exerts a stronger gravitational pull than the moon, it lags behind between 56 and 59 microseconds each day, or about one second every 46.5 years. This impacts essential synchronous operations of future electronic equipment on the lunar surface, which could be alleviated by a standardized conversion system between Earth and moon time zones.

The moon's little-known, incredibly thin atmosphere

Earth's colorless, lifeless moon is often portrayed as devoid of an atmosphere. However, this fascinating article describes the very thin layer of gases floating above the surface of our celestial neighbor, a layer so thin it's technically known as...

The moon is moving 3.8 centimeters farther away from Earth each year

Driven by tidal forces, the effect is minimal and slow, ensuring stable tidal patterns and lunar cycles. Earth's rotation slows down as the Moon gains orbital momentum, slowly lengthening the day over time.

Geological tremors on the moon provide evidence that it is shrinking

Apollo seismometers have collected moonquake data, which scientists have analyzed to map the moon's interior and reveal that fault slips producing tremors are the result of sublunar cooling and contraction. It also revealed that the moon's inner core is about 500 kilometers (311 miles) across.

Lasers have been used to create natural adhesives for paper

German researchers at four Fraunhofer institutes have developed a method to seal paper packaging using a carbon monoxide laser. Without the need for glue or plastic adhesives, the Papure project is expected to improve the recyclability of paper. (Some readers may experience a paywall.)

Paper check usage is down 83% over 25 years

At the start of the millennium, more than 68 million checks were processed daily. Amid the adoption of automated clearinghouse (ACH) payment systems, that number has sunk to 12 million a day.

The lifespan of a dollar bill

Durable, made of a cotton blend, and with billions in circulation, the common dollar bill is made to last. This video from 1440 goes inside the life of the country's paper currency, from printing to purchasing, in this quick 60-second overview.

If the moon were less than one-twelfth its current distance from Earth, the planet's tidal forces would overcome the moon's internal gravity, tearing it apart and forming a ring of debris.

Because it loses more atmospheric gas to outer space than the cosmic dust it collects as it moves through space, the Earth loses about 50,000 metric tons of mass every year.

Our brains trick us into seeing an enlarged Moon when on the horizon

Humans perceive the sky as a flattened bowl and judge the size of an object by accounting for its perceived distance away from us. Combined, studies have found that the Moon on the horizon is perceived to be larger because the terrain makes it seem like it is farther away, similar to the Ponzo illusion.

Watch a visualization of what it would look like to move along Earth's surface as fast as the International Space Station, or about 23 times the speed of sound.

The applications and industrial uses of graphene, the single-atom-thick material

Shortly after its discovery in 2004, the strength, flexibility, optical properties, and conductivity of this thin layer of carbon atoms earned it the designation of a "wonder material," but breakthroughs in its use have taken decades of research. As of 2026, graphene-enhanced electronic sensors, optical microchips, concrete, and supercapacitors are available, though scale production challenges remain.

Earth's total mass is equivalent to 13 quadrillion Egyptian pyramids of Khafre

Newton's law of universal gravitation was used to calculate the value after Henry Cavendish torsion balance experiments determined the missing value of the universal gravitational constant from Newton's equation.

If there were a swimming pool on the moon, where gravity is about one-sixth that of Earth, championship finswimmers could potentially launch themselves up to 5 meters (16 feet) in the air.

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.

Zooming out from Earth to the edge of space

For perspective on the universe's absolute massiveness, watch this four-minute video. Beginning at a facility in Germany, the "camera" pulls back revealing the surrounding countryside, Germany itself, Europe, the Earth, and so on. At one point stars form galaxies and galaxies, at a distance, become as seemingly "small" as the individual stars.

In the third century BCE, the Greek astronomer Aristarchus of Samos estimated the distance to the moon using geometry after measuring the length of Earth's shadow during a lunar eclipse.

The weight of Earth's atmosphere is equivalent to a 33-foot deep, global ocean

Because air is made up of gas molecules with mass, it is not weightless. On the planet's surface, we are effectively living in what is the equivalent of the bottom of an invisible ocean of these particles pressing against us, just as water molecules do when we are submerged.

Microgravity environments improve the success of 3D bioprinting

Gravity can cause gaps, such as those in the chambers of a 3D-printed heart, to collapse before stem cells, hydrogels, and biochemicals bind together during the bioprinting process. Rather than Earth's surface, some bioprinting is done on the International Space Station, where defective organs are also printed to test treatment methods.

In a standard deck of 52 cards, shuffling produces one of approximately 8.07 × 10⁶⁷ potential card orders—a number about as large as the number of atoms in the Milky Way.

Watch how DNA is packaged to a 10,000th of its original size in a cell

In humans, the 2-meter (6.56-foot) molecule wraps around spool-like proteins called histones, forming beads—nucleosomes—that fold up into fibers. These fibers—chromatin—form loops through folding that compress into larger fibers, which tightly coil together to form a chromosome.

Why some people say the moon is made of cheese

Mental Floss digs into the history behind the fable, which dates back as far as the 1500s, when it was mentioned in "The Proverbs of John Heywood." Even NASA has gotten in on the joke, tweeting a (supposedly) doctored photograph showing the moon's expiration date.

Units involving light, such as light-seconds and light-years, describe the distances traveled by light across that amount of time.

The moon is slowly contracting as its interior cools, creating moonquakes and lobate scarps—cliffs that are steep on one side and gently sloping on the other—as the moon's surface buckles.

As of 2025, the Factory of the Future 1.0 is the world's largest 3D printer

Housed at the University of Maine, the machine incorporates AI and can utilize bio-based materials to construct homes exceeding 3,000 square feet in size. Homes made from these materials are fully recyclable, as their components can be deconstructed, ground up, and reused as raw materials for printing.

A map of the moon, using lidar

When planning to land on the moon, knowing the topography matters. This map of the lunar surface was created by using 6 billion measurements from NASA's Lunar Orbiter Laser Altimeter, a type of lidar. Check out the technically accurate depths of craters and ancient oceans on our beloved lunar neighbor with this fun, impressive map.

Moon 101: NASA's complete overview of our lunar companion

From modulating our tides to impact our climate, Earth's lone natural satellite plays a key role forming the planet's habitat. Before diving into the rest of the resources on this page, check out NASA's overview of the basics of the Moon—how it got its name, its size and distance from Earth, its structure, and much more.

Paper boarding passes have become rarer in recent years

Many travelers have shared their attachment to the documents as their utility fades. This sharply illustrated timeline reviews the development of the paper boarding pass as technology evolved.

Visualizing Earth's space garbage

An unsavory byproduct of humanity's brilliant exploration of space, the Moon, and more, is the rapid production of space debris floating around in orbit. Its estimated over 25,000 objects are in orbit, a number that grows everyday as satellites are decommissioned, rockets enter orbit, and more. Now, you can visualize what this debris looks like from a zoomed-out perspective with this brief video.

Just as the moon deforms the Earth to create tides, Jupiter deforms its moon, Io, generating the thermal energy in Io's interior that powers the more than 400 volcanoes on its surface.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Anticipating moon tourism by 2000, Pan Am issued 'First Moon Flights' club cards

More than 93,000 cards were issued between 1968 and 1971, creating a waitlist that began when Gerhard Pistor, an Austrian journalist, visited a Viennese travel agency to request a flight to the moon. The cards were issued at no cost and numbered in the order they were issued.

Lining up every microbe on Earth would stretch to about 105,000 light-years

There are about 10²⁷ such organisms on the planet, many of which are adapted to produce energy through uncommon reactions in unconventional environments, such as within rocks or near volcanoes on the ocean floor. Studies of these organisms have reframed astrobiologists' search for life beyond Earth by broadening the parameters under which life can exist.

Some maps may incorrectly identify the boundaries of a solar eclipse's totality because they assume the Earth is a smooth surface.

NASA funded research into creating pizza with a 3D printer

The agency awarded a contract for the development of devices that can create edible structures from long-lasting dry powders when mixed with liquids or pastes. By delaying this integration until the time of consumption, food could last longer than the current six-month expiration of freeze-dried meals for Mars expeditions.

Voyager 1 captured Earth as a 'Pale Blue Dot' from 6 billion kilometers away

On Feb. 14, 1990, NASA's Voyager 1 space probe took the farthest photo of Earth ever captured. Earth appears so small in the image that it takes up less than a single pixel out of 640,000 in the photo's frame.

Mass market paperbacks—the chunky, cheaply made books—were originally designed to fit in a pocket.

The crew of Artemis II captured a photograph of Earth setting as they orbited the moon

On April 6, 2026, the Artemis II astronauts captured a striking image of Earth setting as their spacecraft orbited the Moon, echoing the iconic Earthrise photo taken by Apollo 8's Bill Anders 58 years earlier.

Solar eclipses are a cosmic coincidence because the moon is 400 times smaller than the sun but about 400 times closer to Earth, allowing it to block sunlight for those on Earth within its shadow.

How the moon moves, an interactive lesson

How exactly does the moon move, and why does it move that way? In this ridiculously comprehensive interactive explainer, you can conduct experiments to see how the moon rotates and as it moves around the Earth, while learning how gravity works by controlling the path and speed of different objects. Dive into this beautiful, simple explainer to learn the basics on gravity and the moon.

Earth's circumference was estimated over 2,000 years ago using geometry and shadows

By measuring the angle of the shadow cast in Syene when no shadow was cast in Alexandria, Eratosthenes used the distance between the two cities and trigonometry to estimate the Earth's circumference to within a few percentage points of the actual value.

Explore how far you've traveled through space while living on Earth

Using the "Cosmic Odometer," users can enter their birthday and learn how far they have moved through space due to the combined effects of Earth's rotation around its axis, the planet's orbit around the sun, the solar system's trajectory through the Milky Way, and the galaxy's motion through the universe.

If the Earth stopped spinning, 85% of the world's population would experience supersonic winds

The planet's equator moves about 470 meters per second—over 1,000 miles per hour—and air there would continue moving at this speed for several minutes if the ground stopped rotating. These conditions would cause tsunamis, global storms, and fling debris fast enough to destroy nearly all human-made structures.

How 3D printing inside cells paves the way for microscopic machines

In 2026, scientists in Slovenia developed a method to 3D print a small elephant, several microscopic geometric objects, and barcodes for cell labeling within living human cells, which continued to grow and divide thereafter. The experiment opens the door to fabricating devices within cells to study and manipulate cellular functions.

Over thousands of years, the frequency of solar eclipses is greatest around the Arctic and Antarctic Circles and lowest near the equator.

Dive into the fascinating journey of a Federal Reserve note

Ever wondered how long an individual dollar bill lasts? After cash is designed and produced, money circulates in the economy, with $100 bills staying in use for the longest on average—roughly 15 years—and the $10 lasting just less than five.

A solar eclipse viewer can be made from everyday objects, such as a cereal box, aluminum foil, tape, and paper, to safely view the cosmic event.