Mars is the fourth planet from the sun and has a distinct rusty red appearance and two unusual moons. The Red Planet is a ...

Earth, our home planet, is a world unlike any other. The third planet from the sun, Earth is the only place in the known universe confirmed to host life. With a radius of 3,959 miles, Earth is the ...

The rusty world is full of mysteries—and some of the solar system's most extreme geology. Learn more about Earth's smaller, colder neighbor.

How far it is from the sun: 886 million miles (1.4 billion kilometers), on average How big it is: 72,400 miles (116,500 km) across, or almost 10 times the size of Earth. How many moons it has: At ...

1. Earth is not a perfect sphere. Yes, we've all been taught that the Earth is not flat, but it may shock you to learn that it's not perfectly spherical either. As the National Oceanic and Atmospheric ...

There are secret planets hidden inside Solar Smash—and today we’re unlocking them all! From turning Earth into a frozen ice cube to triggering insane planetary destruction, each secret world requires ...

But Phobos won't zip around Mars forever. The doomed moon is spiraling inward at a rate of 1.8 centimeters (seven-tenths of ...