Explanation:
Every eleven years, our Sun goes through a solar cycle.
A complete
solar cycle
has now been imaged by the sun-orbiting
SOHO
spacecraft,
celebrating the 12th anniversary of its launch yesterday.
A solar
cycle
is caused by the changing
magnetic field of the Sun, and varies from
solar maximum,
when
sunspot,
coronal mass ejection, and
flare phenomena are most frequent,
to solar minimum, when such activity is relatively infrequent.
Solar minimums occurred in 1996 and 2007, while the last solar maximum
occurred in 2001.
This
picture is composed of a SOHO image of the
Sun in extreme
ultraviolet light for each year of the last
solar
cycle,
with images picked to illustrate the relative
activity of the Sun.
