period of rotation वाक्य

Historically, a second obstacle has been that Mercury's period of rotation is a slow 58 Earth days, so that spacecraft flybys are restricted to viewing only a single illuminated hemisphere.
However, we want our orthogonal trajectories to span every point on every circle, which means that f ( \ theta ) must have a range which at least include one period of rotation.
Artificial satellites that need to face the Earth at all times must be carefully spun so that their period of rotation matches their period of revolution, and this synchronization maintained by use of attitude controls.
Their period of rotation shortens dramatically as the stars shrink ( due to conservation of angular momentum ); observed rotational periods of neutron stars range from about 1.5 milliseconds ( over 600 revolutions per second ) to several seconds.
During the last 620 million years the period of rotation of the earth ( length of a day ) has increased from 21.9 hours to 24 hours; in this period the Earth has lost 17 % of its rotational energy.

Lightcurve data for Europa have been particularly tricky to interpret, so much so that for a long time its period of rotation was in dispute ( ranging from 5 and a half hours to 11 hours ), despite numerous observations.
Due to Mercury's 3 : 2 spin orbit resonance, a solar day ( the length between two transits of the Sun ) lasts about 176 Earth days . A sidereal day ( the period of rotation ) lasts about 58.7 Earth days.
This means that although a sidereal day ( the period of rotation ) lasts around 58.7 Earth days, a solar day ( the length between two transits of the Sun ) lasts around 176 Earth days . ( In contrast, the difference between Earth's sidereal and solar days is only 4 minutes .)