rotation. Here’s the puzzle: That is about 6 minutes, or one percent, longer than the radio rotational period measured by the Voyager 1 and Voyager 2 spacecraft, which flew by Saturn in 1980 and 1981.

Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes and 4 seconds with respect to other distant stars. Scientists call this difference crucial to ...

A day on Neptune lasts precisely 15 hours, 57 minutes and 59 seconds, according to the first accurate measurement of its rotational period made by University of Arizona planetary scientist Erich ...

Hi’iaka is the larger outer satellite of the dwarf planet Haumea. Using relative photometry from the Hubble Space Telescope and Magellan and a phase dispersion minimization analysis, we have ...

Astronomers have found that the rotational profile of a nearby star, V889 Herculis, differs considerably from that of the Sun. The observation provides insights into the fundamental stellar ...

For nearly a billion years, Earth’s rotation stopped slowing down. Locked in a rare cosmic balance, the planet’s day remained fixed at 19 hours, stalling the normal progression toward longer days.