A planet's north pole is defined by its position relative to the solar system's invariable plane. The invariable plane is a fixed reference point perpendicular to the solar system's rotation. A planet ...

Astronomers using NASA’s Hubble Space Telescope have measured the rotation rate of an extreme exoplanet by observing the varied brightness in its atmosphere. This is the first measurement of the ...

Our Earth is well-suited for life because it is perfectly spit-roasted by our Sun thanks to our planet’s axial rotation — but other planets aren’t so lucky. A new study from Peking University reveals ...

Tracking the rotation speed of solid planets, like the Earth and Mars, is a relatively simple task: Just measure the time it takes for a surface feature to roll into view again. But giant gas planets ...