Astronauts on the International Space Station will sit down to a very special meal tomorrow as they become the first people to ever eat vegetables grown on the station itself.

Members of the Expedition 44 team will tuck in to the fruits (and veg) of labour of NASA's Veg-01 experiment resulting from food growth technology aboard the station's orbiting laboratory - appropriately named Veggie.

A crop of red romaine lettuce will top the menu after being harvested 33 days after initially being planted. This is the station's second batch of produce grown in the Veggie greenhouse, with the initial produce having been returned to Earth in October 2014 for food safety analysis.

The experiment is part of a wider mission to create sustainable conditions for NASA's ongoing Journey to Mars program, with Veggie representing a viably sustainable food source that can be cultivated deep in space, far away from the reach of resupply shuttles.