Launch window: 发射时限

美国国家航空航天局6月30日宣布，将于7月13日进行继“哥伦比亚”号失事以来的首次航天飞机发射，届时“发现”号将搭载7名宇航员和一些急需的物资和部件飞往国际空间站。外电报道如下：NASA announced on Thursday it has set July 13 for its first misson of space shuttle launch since the 2003 Columbia disaster.

"Based on a very thorough and very successful flight readiness review, we're currently go for launch of Discovery on July 13," NASA administrator Michael Griffin announced the decision after a two-day meeting of the US space agency to review Discovery's flight readiness. The planned launch window is from July 13 to 31.

"We believe this is the cleanest flight we have ever done," he said, "It's risky; we've done what we can do to minimize that."

Launch window表示“（宇宙飞船的）发射时限，最佳发射时机”，是一段短暂、特定的时间，必须在此期间内发射太空飞船或火箭，以便完成使命或达到预期效果。

据悉，“发现”号航天飞机原定于今年5月中旬升空，但由于发现新的安全隐患而一度推延。
由于发生了“哥伦比亚”号失事惨剧，美国航空航天局为这次时隔两年之久的发射进行了细致准备，也对可能发生的危险做出了大胆假设。如果“发现”号在发射途中再次遭遇不可修复的损坏，宇航员们将在国际空间站等候“阿特兰蒂斯”航天飞机前去营救。