DATE=2/21/2000 TYPE=CORRESPONDENT REPORT TITLE=SHUTTLE (L-UPDATE) NUMBER=2-259414 BYLINE=DAVID MCALARY DATELINE=WASHINGTON CONTENT= VOICED AT: /// EDS: UPDATES CR 2-259392; SHUTTLE LANDING SCHEDULED FOR 2152 UTC TUESDAY / 4:52 P.M. EST /// INTRO: Astronauts aboard the U-S space shuttle Endeavour completed mapping Earth by radar Monday and began preparing for their return home, but not without anxious moments. As V-O-A science correspondent David McAlary reports, the 60-meter-long radar mast that was key to the mission's success had trouble retracting. TEXT: Endeavour's crew shut down two radar systems that spent almost 10 days gathering data for a three- dimensional topographical map of most of Earth's terrain. But automatic retraction of the mast almost failed when the structure got stuck -- just centimeters before it was fully collapsed inside its stowage compartment -- and the container door would not latch. Mission officials had anticipated potential problems with the hardware before the mission began. // OPT // They originally scheduled a standby spacewalk for astronauts to manually retract the boom, which is the longest rigid structure ever erected in space. But they cancelled the spacewalk -- thinking the risk of problems low -- and used the allotted time to extend radar activities for mapping more of Earth. // END OPT // When the retraction difficulty arose, flight controllers considered releasing the stubborn boom into space. But the closure finally succeeded when the hardware warmed in the sun for two hours, and the astronauts increased the force of the retraction motors. Thanks to extended time for their radar-mapping, the astronauts covered virtually 100 percent of the land areas scientists had targeted. Mission control in Houston (Texas) thanked the six Endeavour crew members for a job well done. /// MISSION CONTROL ACT /// We would like to congratulate you on a flawless operation of this most sophisticated mapping instrument in the universe. The mapping data you have collected are some of the most valuable accomplishments in the history of space flight, and this topographic database will be a real treasure to the human race for many years. /// END ACT /// The astronauts are bringing back more than 300 tapes filled with digital images of Earth's land surfaces. // OPT // U-S space agency project scientist Mike Kobrick and colleagues will take up to two years transforming them into the most complete and detailed three-dimensional computerized terrain maps ever produced, of regions where 95 percent of the world's population lives. /// KOBRICK ACT /// Maps are really basic to all of human activity. The first world map that we know of was on a Babylonian clay tablet -- 600 years before the Christian era, I think. It was mostly incorrect, but we fixed that. Now we have a map of the world at 30-meter resolution -- not just an image of the world, not just a road map, but a three-dimensional map. It's a truly astounding achievement that will stand the test of time. /// END ACT /// /// END OPT /// Endeavour is scheduled to land in Florida later today [Tuesday], but flight directors say bad weather may delay the touchdown or force it to another site on the U-S West Coast. (Signed) NEB/DEM/TVM/WTW 21-Feb-2000 19:19 PM EDT (22-Feb-2000 0019 UTC) NNNN Source: Voice of America .