STS073-708-089 (26 October 1995) --- As evidenced by this 70mm photograph from the Earth-orbiting Space Shuttle Columbia, international borders have become easier to see from space in recent decades. This, according to NASA scientists studying the STS-73 photo collection, is particularly true in arid and semi-arid environments. The scientists go on to cite this example of the razor-sharp vegetation boundary between southern Israel and Gaza and the Sinai. The nomadic grazing practices to the south (the lighter areas of the Sinai and Gaza, top left) have removed most of the vegetation from the desert surface. On the north side of the border, Israel uses advanced irrigation techniques in Israel, mainly "trickle irrigation" by which small amounts of water are delivered directly to plant roots. These water-saving techniques have allowed precious supplies from the Jordan River to be used on farms throughout the country. Numerous fields of dark green can be seen in this detail