Skip to main content

Whirling Dervish: Fastest-Spinning Exoplanet Beta Pictoris b Explained (Infographic)

Diagram of day length on various planets.
On Beta Pictoris b, a planet still forming nearly 64 light-years away, a day lasts only 8.1 hours. (Image credit: By Karl Tate, Infographics Artist)

Planets acquire their rotation when they are formed, taking angular momentum from the impacts that shape them. There is a relationship between the mass of a planet and the speed of its spin, except where tidal forces have decelerated planets and made their days longer.

Main Story: Length of Alien Planet's 'Day' Clocked for First Time, an 8-hour World

Exoplanet Beta Pictoris b is the fastest-spinning known planet.

Beta Pictoris b in Pictures: An Alien Planet Image Gallery

At between 8 million and 20 million years old, the Beta Pictoris system, 63.4 light-years away, is still in its formative stage. Young planets are still accreting as planetesimals collide in the debris disk that surrounds the star.

Follow us @Spacedotcom, Facebook and Google+.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: