Rain, overcast skies delay space shuttle's return

[April 20, 2010]  CAPE CANAVERAL, Fla. (AP) -- Rain and overcast skies prevented space shuttle Discovery from returning to Earth on time Monday, and NASA aimed for the morning's second and final landing opportunity in hopes the weather might improve.

Mission Control radioed up the disappointing news at daybreak.

"I know you guys are working it hard," said shuttle commander Alan Poindexter. "We'll look forward to maybe an improved weather picture here in about an hour and a half."

"We'll keep our eye on it and let you know," replied Mission Control.

By dawn, the rain that drenched Florida's Kennedy Space Center overnight had started moving offshore. But thick clouds lingered as did some rain, and Mission Control didn't want to take any chances.

If the weather improves in time for the second landing attempt at 10:23 a.m., Discovery would crisscross the United States on its trip home from the International Space Station.

The streaking, glowing trail would be visible from the ground, weather permitting, as the shuttle passes above Washington state and descends over America's heartland: Idaho, Wyoming, Colorado, Kansas, Oklahoma, Arkansas, Mississippi, Alabama and down into southwestern Georgia and the Florida panhandle.

The last time a shuttle descended over so much of the United States was in 2007. After this mission, no more such re-entries are planned as the shuttle program draws to a close. NASA has tried to keep continental flyovers to a minimum for public safety reasons, ever since Columbia shattered over Texas in 2003.

Typically, a shuttle returns from the southwest, zooming up over the South Pacific, Central America, and the Gulf of Mexico. NASA changed Discovery's flight path before liftoff on April 5, to maximize the crew's work time in orbit and reduce fatigue.

The volcanic eruption in Iceland, at least, was not interfering with NASA's effort to bring Discovery home. The re-entry path does not go anywhere near the European airspace threatened by volcanic ash.

Mission Control said if Discovery can't return to Earth on Monday, the Florida forecast looks more promising for Tuesday and there's always the backup touchdown site in Southern California. The shuttle has enough supplies to remain in orbit until Wednesday.

The astronauts are wrapping up a successful two-week trip to the space station. They left behind tons of science experiments and equipment so the orbiting outpost can operate for years to come. Their biggest contribution was a new tank full of ammonia coolant; it took three spacewalks to hook it up.

A pressure valve in the space station's cooling system got stuck after the ammonia tank was plugged in. Astronauts will have to deal with the problem on a future spacewalk. For now, though, the lab complex is being cooled properly.

This is Discovery's next-to-last flight. NASA has only three shuttle flights left before retiring the fleet. Atlantis is next up in less than four weeks. The final shuttle mission -- by Discovery -- is scheduled for September.

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On the Net:

NASA:
http://www.nasa.gov/mission_pages/
shuttle/main/index.html

NASA:
http://spaceflight1.nasa.gov/realdata/sightings/

[Associated Press; By MARCIA DUNN]

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