Mir Trip In Holding Pattern

The space shuttle Atlantis sits poised for launch and surrounded by uncertainty.

Tonight’s blastoff is supposed to start U.S. astronaut David Wolf’s three-month assignment aboard the problem-plagued Russian space station Mir.

It is possible Wolf may be left behind.

Lingering safety concerns and growing political pressure in Washington have triggered unprecedented last-minute reviews of Mir’s health. A task force headed by former astronaut Tom Stafford and another by A. Thomas Young, a retired space/ defense executive, briefed NASA Administrator Daniel Goldin on their findings late Wednesday.

Goldin, just back from Russia, said he will wait until the last possible moment today before deciding whether to let Wolf go.

The announcement is expected at 9 a.m. EST. The launch is scheduled for 10:34 p.m.