Picture of the day - December 29, 2007

"Where day meets night"

Photo courtesy of NASA. As the earth spins on its axis, half of the planet's surface is always facing the sun (day) while the other half is dark (night), and the lines on either side where day and night meet (called the terminators) are quite interesting indeed. Since the earth is constantly spinning, the terminators are constantly "moving" across the planet from east to west. And as you can see in today's amazing picture these lines where day meets night aren't well-defined lines at all! The transition from day into night (twilight) and night into day (dawn) are gradual processes that take several minutes to complete - and that's a very good thing. After all, can you imagine being outdoors when all of a sudden the daylight gives way to complete darkness as if someone has just flipped off a switch? Why the result would be utter chaos! The next time you find yourself witnessing a beautiful sunrise or sunset, remember this picture. The spot of ground you'll be standing on will be at one of the earth's terminators, and you'll be enjoying one of God's most precious gifts.   Click here to comment on this picture.   Visit the POTD Archives for previous "Pictures Of The Day"!     Submit a photo of your own!            Why I publish the "Picture of the Day"