NASA: 'Delicious' lettuce has been successfully grown on the International Space Station

Lettuce has been grown on board the International Space Station (ISS)!

And NASA scientists say it's just as tasty - and as nutritious - as lettuce grown on Earth.

In fact, NASA found the lettuce grown on the space station was richer in nutrients like potassium, sodium and zinc, compared to the stuff here.

Astronaut Steve Swanson harvests some of the crop in June 2014

The lettuce crops were grown in sealed units on the ISS in special ceramic soil under special red lighting.

They took between 33 and 56 days to grow and the plants were watered by the astronauts using an injection through a tube.

Astronauts Scott Kelly and Kjell Lindgren taste the lettuce grown onboard the ISS in August 2014

When the lettuce was fully grown some of it was eaten and some of it was sent back to Earth for scientists to analyse.

Now a study of the lettuce has been carried out, showing how it compares to lettuce grown on Earth.

Growing food in space is important for long space mission, especially if any astronauts end up going to Mars!