News broke today that the Stuxnet virus–widely believed to be a U.S.-created weapon to disrupt Iran’s nuclear program, now rampaging across the Internet like a mad dog–had infected a Russian nuclear facility. But renowned security expert Eugene Kapersky also revealed that Russian astronauts spread a computer virus to the International Space Station (ISS).

So, will the ISS fall out of the sky?

If it was going to, it would have happened already. The infection happened some time ago; Kapersky declined to discuss how significant the infection was to the space station, stating instead that he had been told of virus infections on the station from time to time. As far back as 2008, ISS laptops were infected, but NASA described the infection as a nuisance affecting non-critical systems like email, as the virus was ostensibly designed to steal credentials for online video games (but may actually have been designed by the U.S. and Israeli governments). Even then, NASA emphasized that infections happened on occasion.

So long as the virus infects only the laptops that the crew works on, however, the space station’s operations shouldn’t be affected. A virus could jump around the local network that connects the laptops and could (worst-case scenario) shred millions of dollars of experimental data by wiping laptop hard drives, says a security expert in New Scientist’s story on the 2008 infection.

But–duh–the ISS is in space, and not connected to the Internet. The ISS’s only wireless communication is through Ku band (“under K-band”), the frequency range used by TV stations to communicate with satellites. In other words, unless someone formats a virus to beam up 250 miles to the space station, it’s hitching a ride with the astronauts. And sure enough–the second round of Stuxnet infections in the ISS were traced back to a USB device carried by Russian astronauts. “What goes around comes around,” Kapersky said. “Everything you do will boomerang.”