Computer simulations suggest that there is an undiscovered Earth-like planet lurking in the distant ... [+] Kuiper Belt, well past the orbit of Neptune (artistic illustration). There may be an ...

A distinctive blue and green image of Earth reveals our planet's most remarkable features. At 4.54 billion years old, our home world is a venerable object. But it was only with the arrival of the ...

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 ...