autumnal equinox en Fall is officially here! <p>The autumnal equinox happened today at 5:05 a.m. ET. It marks the beginning of autumn in the northern hemisphere and spring in the southern hemisphere.</p><p>It&rsquo;s the time of year when temperatures start to drop and the days start to get shorter.</p><p>Every year there are two equinoxes, one in March that marks the beginning of spring and one in September that marks the beginning of fall.</p><p>National Geographic explains:</p><blockquote><p>The autumnal equinox and vernal equinox are also the only days of the year when a person standing on the Equator can see the sun passing directly overhead. On the Northern Hemisphere&#39;s autumnal equinox, a person at the North Pole would see the sun skimming across the horizon, signaling the start of six months of darkness. On the same day, a person at the South Pole would also see the sun skim the horizon, beginning six months of uninterrupted daylight.</p></blockquote><p>Equinoxes explained:</p><p></p><p> Fri, 23 Sep 2011 17:11:29 +0000 Mercedes Mejia 4283 at Fall is officially here!