Question

The fairly regular pattern that the number and distribution of sunspots follow, in which the average number of spots reaches a maximum every 11 or so years, and then falls off to almost zero is _____________.

a) Solar minimum
b) Solar maximum
c) Solar cycle
d) Solar prominence

Answer 1

The pattern of sunspot activity, which peaks roughly every 11 years before diminishing, is known as the solar cycle.

Step-by-step explanation:

The fairly regular pattern that the number and distribution of sunspots follow, in which the average number of spots reaches a maximum every 11 or so years, and then falls off to almost zero, is known as the solar cycle. Heinrich Schwabe was the astronomer who observed that the total number of sunspots visible on the Sun was significantly higher during certain times, called periods of sunspot maximum, as opposed to other times, known as periods of sunspot minimum.

While individual spots are short-lived, during the sunspot maxima, it is possible to see over 100 sunspots at once, although they still cover less than one-half of one percent of the Sun's surface. The number of sunspots then decreases towards the solar minimum, when sometimes no spots are visible.

These observations led to understanding that the Sun operates on an 11-year cycle, with variations between 9 and 14 years. The Sun's most recent activity maximum was experienced in 2014.