Foreshadowing means
a. describing what happens at night—for example, in a dark basement.
b. showing the readers the dark side of a character's personality.
c. hinting at things that will occur later.
d. putting secondary characters in the foreground of the story.

the circled areas are referred to   as sunspots.   the sunspots are cooler than the   surrounding area.

sunspots are temporary phenomena on the photosphere of the sun that appear visibly as dark spots compared to surrounding regions. they correspond to concentrations of magnetic field flux that inhibit convection and result in reduced surface temperature compared to the surrounding photosphere.