Washington, Aug 11 (IANS): The six astronauts currently living on the International Space Station (ISS) have become the first people to eat food grown at the Veggie plant growth system aboard the orbiting laboratory in space.

In a 15-second video released by the US space agency, three astronauts Scott Kelly, Kjell Lindgren and Kimiya Yui are seen eating the fruits of their labour.

The fresh "Outredgeous" red romaine lettuce that accompanied the crew’s usual freeze-dried fare, however, is far from the first crop grown on a space station.

For decades, NASA and other agencies have experimented with plants in space, but the results were always sent to Earth for examination, rather than eaten.

A number of technologies NASA has explored for these space-farming experiments also have returned to Earth over the years and found their way onto the market.

The Veggie system produced this most recent crop of lettuce.

Not only does its greenhouse lighting technology take advantage of the efficiency of LEDs, which waste almost no energy on heat, but its variable light output allows it to be adapted to specific plant species at specific growth stages.

"It can also sense the presence of plant tissue and only power nearby LEDs. Overall, it uses about 60 percent less energy than traditional plant lighting systems,” NASA said in a statement.

As the space agency eyes deep-space missions like a trip to an asteroid or Mars, space farming becomes less of a novelty and more of a necessity.

Plants will be an integral part of any life-support system for extended missions, providing food and oxygen and processing waste.

Significant further advances will be necessary, and each of them promises to bring new innovations to agriculture here on Earth.