NASA delays space shuttle launch a fourth time

NASA delayed the launch of space shuttle Discovery for a fourth time on Friday amid valve concerns, and managers are uncertain when the flight will take place. Following a 13-hour meeting at Kennedy Space Center, shuttle managers decided against launching next week. The launch had been targeted for no sooner than Feb. 27; no new date was set. Officials said they believe they have a realistic shot at launching Discovery to the international space station before mid-March. After that, the shuttle would have to get in line behind a Russian Soyuz launch with a new space station crew, and the next opportunity for Discovery would be after April 6. More

(Source: Associated Press - Feb 23)