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 ...

THE first edition of this dictionary was published in 1920. Nine years later a second edition appears. Clearly the scientific workers for whom it was compiled have found the book useful. A Dictionary ...

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 ...

The definition of "planet" has for some time been the subject of intense debate. Although the word dates back thousands of years, no officially decreed scientific definition of "planet" existed before ...

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 ...

On Sunday, The New York Times reported that the Trump administration plans to define “gender” based on people’s external genitalia, as part of their larger efforts to roll back protections for ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...