Rocket salad in the making

Most people associate Nasa with rocket science but now the American space agency has turned its attention to rocket salad.
A portable greenhouse to grow lettuces was taken to the International Space Station (ISS) during last week's supply mission.
Provided that the astronauts can cut the mustard, they should be eating their first homegrown space salad before the end of the year.
This will be the first time a Nasa astronaut has tasted something grown in orbit.
Until now, all supplies have been taken from Earth. But, according to Dr Gioia Massa, a payload specialist at the Kennedy Space Centre, Florida, there is no reason why this has to be the case.
"If you can get the environmental conditions correct, there's no reason why plants won't grow pretty well in space," she says.
She was inspired to grow plants in space in the 1980s during an agriculture class when she was 13.
Now her deployable vegetable production system (Veggie for short) is on board the ISS and ready for business. It is a pop-up greenhouse that collapses to the size of a briefcase for stowage during launch.
The main obstacle to growing plants in space is the lack of gravity, since the soil tends to float away.
Massa's solution has been to design the equivalent of something familiar to all tomato wranglers: a grow bag. The space agency calls these "plant pillows".
Three plant pillows have been taken up to the ISS and will be sown in succession. Two hold seeds for a variety of red romaine lettuce called Outredgeous.
No matter how appetising Veggie's first crop looks, the astronauts will freeze the lettuces and send them back to Earth for analysis in August.