• Right image: Earth, as seen from the sun, at instant of September 2012 equinox.
• The September equinox falls tomorrow, on Saturday, September 22, at 14:49 Universal Time. At this special moment, the sun will be at zenith - straight overhead - at the Earth's equator. Although the equinox happens at the same instant for everyone worldwide, the clock time for the equinox varies by time zone. In the U.S., the equinox will come on September 22, at 10:49 a.m. EDT, 9:49 a.m. CDT, 8:49 a.m. MDT or 7:49 a.m. PDT.
• Everything you need to know: Sep

tember equinox 2012
• How do I translate Universal Time into my time?
• At the instant of the September equinox, the midday sun will be shining straight overhead at the equator, at about 2.5o of latitude to the north of Sao Luis, Brazil. At this juncture, it'll be sunrise in Alaska, noontime in eastern Brazil, sunset in Saudi Arabia and midnight in Australia. As the September equinox sun crosses the equator, going from north to south, it'll signal the beginning of autumn in the Northern Hemisphere and spring in the Southern Hemisphere.
• On the day of the equinox, the sun rises due east and sets due west all over the world, with everyone worldwide receiving the same amount of day and night. By October, however, that'll change dramatically. By then, the sun will rise noticeably

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