The International Astronomical Union defines a planet as a celestial body that orbits the sun, is massive enough that gravity has forced it into a spherical shape, and has cleared away other objects ...

What is design? What makes it distinct from art, science, or engineering? The editors of this site decide dozens of times a day what is or isn’t “design.” But is it ultimately subjective, or can it be ...

In this video segment adapted from NOVA scienceNOW, learn about the debate over the definition of a planet. Historically, there has been no scientific definition for a planet, leaving astronomers with ...

Who’d have thought such a tiny planet would stir up such a big controversy? Everyone seems to have an opinion on the recent vote by the International Astronomical Union to change the official ...