A lightning strike has shut down the Tevatron particle accelerator.

Although the machine, based in Batavia, Illinois, will only be offline for two weeks for repairs, the time lost is precious as the Tevatron is due to close later this year (see Nature’s editorial Goodbye Tevatron from January).

According to Fermilab, the Department of Energy national lab which runs the collider, storms over the weekend caused damage to one of the magnets used to guide particles around the accelerator. A statement released yesterday says the storms caused a ‘quench’ – a term describing how magnets stop being superconducting and start being conducting. (A quench downed the LHC in 2008.)

As the magnets in particle accelerators must be cooled to very low temperatures to make them superconducting, the Tevatron will have to be warmed up before the magnet can be replaced and cooled down again before it can restart.

In addition to the lightning, a fire at the Soudan mine research facility has disrupted Fermi-linked experiments there. Fermilab’s director Piermaria Oddone said in a statement that “the last few days have been quite challenging”.

“The particular magnet that was damaged on Sunday will take approximately two weeks to replace, and we expect to be back in full operation early in April to continue the last extraordinary run of the Tevatron,” he said. “Although we have replaced damaged magnets before, we have only interrupted operations three times in the past five years for unexpected component replacements.”

In 2006 Symmetry magazine looked at the problems that lightning could cause the Tevatron. Todd Johnson, an operations specialist at the site, told the magazine that a direct strike was not needed to mess up its functions. “When lightning strikes, large currents flow through the ground,” he noted. “The Tevatron is a magnificent and wonderful thing, but it’s also very fragile.”

Or, as Paul Czarapata of the lab’s Accelerator Division, put in back in 2007, “We’re at mother nature’s mercy. Everything in the machine is a synchronized dance on a razor blade.”