"Pursuant to OMB Circular A-1 1, Section 124.2, NASA is hereby submitting a revised shutdown plan in the event of a lapse in appropriations, replacing the plan submitted to OMB on December 16, 1995. In this plan, NASA continues to require each NASA Center to provide protection of life and property. The decision on what personnel should be excepted from furlough is very fact specific, and Directors in charge of NASA Centers are in the best position to make detailed decisions regarding the suspension of ongoing, regular functions which could imminently threaten the safety of human life or the protection of property."
"All but about 500 of NASA's 19,000 civil servants would be furloughed if the Congress and White House fail to reach a deal to keep the federal government operating beyond April 8. Among the employees who would not be allowed to work are those preparing the Space Shuttle Endeavour for its scheduled April 29 launch."
Keith's 8 April update: False alarm - for now.