The electron beam that drives DARHT - the Dual-Axis Radiographic Hydrotest Facility - accidentally zapped some of its own inner workings, contaminating its vacuum chamber with a layer of carbon. Lab officials think it will take about three months to clean up the mess, pushing the first DARHT test, originally scheduled for this summer, out until 2009, lab officials said this morning.

Actually, "first test" is a bit of a misnomer here.DARHT, built to x-ray mock nuclear weapons as they are detonated, was supposed to be up and running in 2003. But when scientists turned it on, it didn't work, leading to a massive rebuilding effort. That effort was finished in May when lab officials announced with some fanfare that DARHT was finished, tested, and ready for business.

(h/t the LANL blog, your best source for lab gossip, some of which is actually roughly true)