Mapping mission cut back

The National Imaging and Mapping Agency has announced that it will not be able to collect all the data it expected during its Shuttle Radar Topography Mission (SRTM).

The SRTM is scheduled for launch today, weather permitting. Space Shuttle Endeavour, equipped with two radar-imaging devices, will collect terrain elevation data of the Earth's surface. NIMA will use the information to create more accurate and detailed maps [see "Space shuttle to deliver 3-D data of Earth," FCW, Jan. 24].

But last week NASA decided to reduce the data collecting time from 10 days to nine, according to Eric Berryman, a NIMA spokesman. The one-day reduction will prevent NIMA from scanning portions of the Earth twice — a requirement for accurate elevation readings, Berryman said.

NASA cut the mission time because of equipment concerns. The 200-foot carbon mast that collects the radar images has never been used in space, and NASA astronauts may need time to fix the arm if it will not extend. There also is a concern that the mast will not retract, and astronauts may need to perform a space walk to repair or detach the apparatus before returning to Kennedy Space Center.

"We are very disappointed because the more information you can gather the better," Berryman said. "But it is better to be cautious."

Up-to-the-minute information on the Shuttle Radar Topography Mission is available at www.jpl.nasa.gov/srtm.