Are There Other Solar Systems?
Exoplanets and the search for other Earths.
Can People Live on Mars?
What would it take to build a human city on the red planet?
Can Plants Grow in Space?
Farming without gravity: how we might grow lettuce on Mars.
Can Real Robots Go to Space?
Meet the mechanical explorers on Mars and beyond.
Can We Hear Sound in Space?
Why the universe is actually completely silent.
Can We Travel Time?
What science says about going into the future or the past.
Could We Live on the Moon?
Building bases and jumping high in low gravity.
Do Other Planets Have Rain?
It doesn't rain water everywhere—sometimes it rains diamonds!
Do Stars Live Forever?
How stars are born, live, and eventually go out.
How Are Planets Made?
Dust, rocks, and gravity swirling together over millions of years.
How Big is the Universe?
Can we reach the edge? How gigantic is everything out there?
How Do Astronauts Sleep?
Strapping into sleeping bags so you don't float away!
How Do Rockets Work?
3... 2... 1... Blast off! The science of going to space.
How Do Satellites Stay Up?
Why don't the communication satellites crash back to Earth?
How Do Space Suits Work?
Why astronauts need big puffy suits to go outside the spaceship.
How Do We Know the Universe is Expanding?
Like a giant balloon, everything is moving further apart.
How Does a Telescope Work?
Using giant lenses and mirrors to see things millions of miles away.
How Far Away is the Moon?
Can we drive a car to the moon? Let's find out how far it is.
How Fast Can a Rocket Go?
Speeding through space faster than a cheetah or an airplane.
How Hot is the Sun?
Learn about our closest star and the incredible heat it makes.
How Long Does It Take to Get to Space?
Is it a quick trip or a long journey?
How Many Moons Does Jupiter Have?
Imagine looking up and seeing a dozen moons in the sky!
How Old is the Earth?
Looking back at billions of years of history.
Is There Gravity in Space?
If things float in space, how does gravity work?
What Are Aliens?
Have we found life on other planets yet?
What Are Constellations?
Connecting the dots with stars in the night sky.
What Are Rings Made Of?
Saturn has beautiful rings, but what are they actually built from?
What Are Shooting Stars?
Are they really stars falling out of the sky?
What Do Astronauts Eat?
Space food isn't just freeze-dried ice cream anymore.
What Happens If You Fall into a Black Hole?
Spaghettification and other wild space mysteries.
What is a Black Hole?
Explore the most mysterious vacuums in the universe!
What is a Comet?
Dirty snowballs flying through the solar system.
What is a Galaxy?
Discover billions of stars swirling together in massive groups.
What Is a Supernova?
The biggest, brightest explosion in the entire universe.
What is an Asteroid?
Giant space rocks floating between Mars and Jupiter.
What Is an Eclipse?
When the moon blocks the sun and turns day into night.
What is Dark Matter?
The invisible stuff that makes up most of the universe!
What Is the Coldest Planet?
Brrr! Pack your warmest jacket for a trip to the icy giants.
What is the Hottest Planet?
It's not the one closest to the Sun! Find out which planet sizzles.
What is the Milky Way?
Welcome to our home galaxy! Learn what it looks like from the outside.
What is the Solar System?
The sun and its family of planets, moons, and rocks.
What is the Space Station?
A giant laboratory floating right above our heads.
Why Are Planets Round?
Gravity squishes everything into a giant ball!
Why Do Stars Twinkle?
Find out why stars look like they are blinking in the night sky.
Why Do We Have Seasons?
The reason for summer, winter, fall, and spring.
Why Does the Moon Change Shape?
From full moon to crescent: the phases of the moon explained.
Why is Mars Red?
The rusty truth about our neighboring planet.
Why is Pluto Not a Planet?
The story of why Pluto lost its planet status.
Why Is Space Black?
If there are so many bright stars, why is the background dark?
Why Is the Sky Blue?
Ever wonder why the sky isn't green or purple?
What is Dark Energy?
The mysterious force hypothesized to be responsible for the accelerating expansion of the universe.
What is Dark Matter?
The invisible substance that makes up most of the universe's mass.