Why NASA ended Cassini’s mission at Saturn
Cassini still worked when it entered Saturn’s atmosphere. Its planned ending protected the moons, used a dwindling resource, and opened a final window into the planet.
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How ISSpresso Made Coffee Work in Space
An espresso machine, a sealed pouch and a capillary cup solved three different problems aboard the space station. Here is what each one did—and what the million-dollar comparison leaves out.
Apollo–Soyuz: When Cold War Rivals Opened the Hatch
The handshake in orbit depended on years of cooperation and hardware designed to meet in the middle.
Gemini 8: Docking, Then a Dangerous Spin
Follow a pioneering orbital docking and the emergency that cut the mission short.
The Tiny Mirror Flaw That Blurred Hubble
A telescope, an optical mistake and the mission to correct its view.
Voyager 1 and the Pale Blue Dot
Look back at Earth through Voyager's camera and consider what a tiny point of light can show.
X-37B and Buran: Returning Without a Pilot
Compare two spacecraft and the problem of bringing a winged vehicle back from orbit.
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Why Did Spaceships Lose Their Wings?
Explore why different spacecraft use different shapes to return to Earth.
Apollo 8 and the View Back at Earth
Follow the Apollo 8 crew to lunar orbit and the photograph that turned their attention home.
How the Sun Can Disrupt a Railway Telegraph
A railway message, a restless magnetic field and the engineering problem we now call space weather.
Why Are the Northern Lights Different Colors?
Trace an aurora's greens, reds and purples to collisions high in the atmosphere.
How Green Is an Electric Car, Really?
Follow the charging cable beyond the car to explore electricity, batteries and lifecycle emissions.
What's Inside This Hole on the Moon?
Explore the Marius Hills pit and the questions scientists ask about the space beneath the lunar surface.
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How Deep Is the Mariana Trench, Really?
Explore ocean depth, pressure and the challenge of picturing the distance to Challenger Deep.
Why the Eiffel Tower Was Almost Demolished
Explore the changing purpose of a landmark that was never meant to be permanent.
How Plastic Can Reach the Mariana Trench
A deep-sea observation raises a question: how can material that floats make its way down?
How Lake Peigneur Swallowed an Oil Rig
Follow the chain of events that connected a lake, a drill and a salt mine.
Why Are Cows Painted in the Sahara?
Rock art opens a window onto a landscape and a climate very different from today's desert.
Finding a Moon Crater Without Seeing the Impact
See how comparing orbital images can reveal a change no one watched happen.
Following the Journey of Malawi's Copper Ingots
Explore what the material in an archaeological object can reveal about its journey.
How Far Did the Deepest Hole on Earth Get?
Compare an extraordinary drilling project with the scale of the planet below our feet.
What Happened Inside Buzludzha?
Look beyond the ruined exterior to the monument's visitors, mosaics and political history.
How Do You Test an Extremely Precise Clock?
What clock comparisons can measure, what uncertainty means, and why a very large number needs context.
How Chandra Found Hidden Cosmic Sources
Discover what X-ray observations can uncover beyond the view of visible-light telescopes.
Why Aren't All Power Lines Underground?
The everyday engineering choices behind overhead lines, buried cables and repairs.
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Why the World Still Has Different Outlets
The standards, installed systems and everyday decisions behind familiar plugs.
What Marie Curie's Notebook Still Carries
A notebook connects the history of radioactivity with the physical traces research can leave behind.
Astronaut Training: Why the Freezing Forest?
Winter camps, underwater rehearsals and cave expeditions prepare astronauts for different parts of a mission. The key is knowing what each exercise can teach—and what it cannot reproduce.
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Nikola Tesla: Electricity and Invention
An illustrated introduction to Tesla and the electrical technologies associated with his work.
Voyager’s Golden Record: What We Sent and How It Works
How Earth’s sounds and pictures fit into a phonograph groove, and how an unknown finder might decode them.
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