Explanation:
Today, the Sun
crosses the celestial equator heading south at 03:09
Universal Time.
Known as an equinox, this
astronomical event
marks the first day of autumn in the northern hemisphere and
spring in the south.
Equinox means
equal
night.
With the Sun on the celestial equator,
Earth dwellers will experience
nearly 12 hours
of daylight and 12 hours of darkness.
Of course, in the north the days continue to grow shorter, the
Sun marching lower
in the sky as winter approaches.
To celebrate
the equinox, consider this view of the Sun in
extreme ultraviolet light from the Sun staring
Solar Dynamics Observatory.
Recorded yesterday, the false-color image shows emission from highly
ionized iron atoms.
Loops and arcs
trace the glowing plasma
suspended in magnetic fields above
solar active regions.