IMAGINE this: you are on an outpost on Mars, and the pressurised greenhouse that is supplying your food and oxygen springs a leak. As its precious contents are exposed to the harsh vacuum of space, starvation beckons. But all is not lost if the leak can be plugged in time. It seems some plants can survive half an hour in a near-vacuum.

Vacuum-like conditions are hostile to life both because they lack oxygen needed for respiration and because water, a component of many living things, boils quickly at low pressure.

To test how plants cope under these conditions, Raymond Wheeler of NASA’s Kennedy Space Center in Florida and colleagues grew radish, lettuce, and wheat plants for 20 days in a chamber at normal atmospheric pressure. Then they pumped the air out, plunging the pressure to just 1.5 per cent of the average air pressure at sea level, for 30 minutes.

After the team returned the pressure to normal, all the plants continued to grow until being harvested a week later. The plants appeared to be just as healthy as another set of plants never exposed to low pressure, with no significant difference in weight (Advances in Space Research, DOI: 10.1016/j.asr.2010.12.017). Only a few other forms of life, such as bacteria, have shown such resilience.


Water evaporated from the leaves when the pressure was reduced, making them wilt temporarily. So Wheeler suspects dehydration, rather than a lack of oxygen, will ultimately kill plants exposed to a vacuum and hopes to test their breaking point in future experiments.

The plants appeared to be just as healthy as control plants that were never exposed to a vacuum

Fred Davies of Texas A&M University in College Station says this is the first experiment to test the effects of a sudden plunge into near-vacuum conditions.

“Plants are very plastic and resilient,” he says.