A galley water heater is being blamed for smoke aboard the International Space Station.
Russian astronauts reported smoke and a burning smell in their main compartment Tuesday. There wasn't enough smoke to activate the alarms or to warrant the use of masks by the six-man crew. The smoke came from a vent and dissipated within a half-hour or so.
Commander Steven Swanson says there was only a small amount of smoke and everyone was fine.
The astronauts quickly disconnected the electric water-heating unit and activated air purifiers in the Zvezda (zuh-VEZ-duh) compartment, Russian for star.
On Wednesday, the astronauts installed a spare unit. NASA says it's working normally.
A similar problem occurred in 2009.
The astronauts say they didn't see anything unusual with the removed device.
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More information: NASA: www.nasa.gov/mission_pages/station/main/index.html