This photo, recorded last June from the International
Sun's limb still peeks above the distant horizon as seen from Earth orbit. Clouds appear in silhouette as
the sunlight is reddened
by dust in the dense lower atmosphere.
Molecules in the more tenuous upper atmosphere are preferentially scattering
On March 20, 2008, the Sun
crosses the celestial equator heading north at 0548
Known as the equinox, the geocentric astronomical event marks the
first day of spring in the northern hemisphere and autumn in the south. Equinox means
night and with the Sun on the celestial equator,
will experience nearly
12 hours of daylight and 12 hours of darkness.
Of course, for those
in the north, the days will grow longer with the
in the sky as summer approaches.
To celebrate the equinox, consider this
colorful view of the setting Sun.