What phenomenon is proven when a sunspot at 15° latitude takes measurably longer to return than one near the equator?
Answer
Differential rotation
Differential rotation is the characteristic behavior where different regions of a celestial body rotate at different speeds depending on their latitude. If the Sun rotated rigidly, like a solid sphere such as Earth, every feature regardless of its latitude would complete a full circuit in the exact same amount of time. The observation that features nearer the equator complete their circuit faster than those observed further toward the poles is the definitive proof that the Sun exhibits differential rotation, a behavior typical of fluid bodies held together by gravity.
Related Questions
Which visual markers are historically significant for charting the Sun's rotation across its surface?What phenomenon is proven when a sunspot at 15° latitude takes measurably longer to return than one near the equator?Why is the synodic period observed from Earth longer than the actual sidereal period of the Sun's rotation?How does analyzing spectral lines via the Doppler effect reveal the Sun's rotational velocity?What are the approximate synodic periods for solar rotation at the Equator ($\pm 5^\circ$) compared to near the Poles?Which European observer is credited with scientifically documenting solar rotation in the early 17th century using charting of sunspots?How does the Sun's differential rotation influence the organization of its magnetic field lines?What modern technique, which studies solar oscillations, allows measurement of rotation in internal layers below the photosphere?According to IAU educational recommendations for visual charting, approximately how long should one track a sunspot to clearly observe the Sun's rotation?How does the rotational behavior of the Sun fundamentally differ from that of a solid ball like Earth?