This Salad Is Outta This World: Astronauts Eat Greens Grown In Space

This Salad Is Outta This World: Astronauts Eat Greens Grown In Space

1:46pm Aug 11, 2015
It took astronauts 33 days to grow enough red romaine lettuce to make a small salad.
It took astronauts 33 days to grow enough red romaine lettuce to make a small salad.
NASA
  • It took astronauts 33 days to grow enough red romaine lettuce to make a small salad.

    It took astronauts 33 days to grow enough red romaine lettuce to make a small salad.

    NASA

  • The plants sprout from artificial "pillows" that mimic soil on Earth.

    The plants sprout from artificial "pillows" that mimic soil on Earth.

    NASA

In space, food is freeze-dried, prepackaged, and frankly not always very tasty. But on Monday aboard the International Space Station, astronauts got a rare treat: fresh lettuce.

The red romaine lettuce was grown by NASA's Veggie project, which has one goal — to bring salad to space.

"It's just one of those things that we have to learn if we're going to step into the solar system and go to Mars," says Trent Smith, the Veggie project manager. "How will you grow your plants?"

NASA YouTube

It turns out, farming in space is not as simple as you'd think. First, there's the problem of water. On Earth, gravity pulls it down toward the roots, but in space, it can ball up in the corner of a pot and leave the roots high and dry. Smith's team has developed a solution: a "pillow" of aerated clay, to which you add water. The clay provides structure for the roots to spread out in zero G.

Second, plants also need fresh air to breathe. On Earth, wind keeps fresh air coming, but inside the space station, there is no wind. So fans must constantly circulate air.

Finally there's the issue of light. The space station is whipping around the Earth fast: "Every 90 minutes there's a new sunrise, so for a plant, that would be extremely confusing," Smith says. The Veggie team added some artificial lights to keep the orbiting lettuce on an Earthly schedule.

The plants sprout from artificial

The plants sprout from artificial "pillows" that mimic soil on Earth.

NASA

The system took years for engineers on Earth to develop. But growing Monday's salad on the space station didn't take long at all.

"July 8 it started. We had 33 days of growth, and the plants were just fantastic, I mean, big, large leaves," Smith says.

The lettuce was ready. The astronauts were hungry. And this morning, there was just one question left: How would the crew take their leafy greens?

The astronauts went with a simple balsamic dressing and reported that the space salad tasted out of this world.

"That's awesome, tastes good," astronaut Kjell Lindgren told mission control in Houston.

This wasn't the first time astronauts had grown lettuce in space. Last year, astronauts grew an equal amount of tasty greens. They were frozen and returned to Earth for careful analysis — though Smith suspects the crew at the time may have sneaked a bite: "I am fairly certain we didn't get all the lettuce home last time," he says.

This lettuce could be just the tip of the iceberg. There are plans for cabbage, cherry tomatoes and even potatoes. As we leaf into the final frontier.

Copyright 2015 NPR. To see more, visit http://www.npr.org/.

Transcript

MELISSA BLOCK, HOST:

Today, aboard the International Space Station, astronauts got a rare treat - fresh lettuce.

(SOUNDBITE OF ARCHIVED RECORDING)

UNIDENTIFIED MAN #1: We're going to get started with the harvesting here in just a couple of minutes. And then right after that, we'll have lunch.

BLOCK: NASA broadcast that space salad meal live. NPR's Geoff Brumfiel reports.

GEOFF BRUMFIEL, BYLINE: In space, food is freeze-dried, prepackaged and, frankly, not always very tasty, which is where Trent Smith comes in.

TRENT SMITH: I am the Veggie project manager. I work here at NASA Kennedy Space Center.

BRUMFIEL: The Veggie project has just one goal - to bring salad to space.

SMITH: It's just one of those things that we have to learn if we're actually going to step into the solar system and go to Mars. You know, how will you grow your plants?

BRUMFIEL: It turns out it's not as simple as you'd think. On Earth, gravity pulls water down towards the roots. But in space...

SMITH: Getting that balance of water right for the root zone is extremely difficult in microgravity just because of the way water behaves.

BRUMFIEL: It can ball up in a corner, leaving roots high and dry. Smith's team has a solution, though - a pillow of clay, air and water that lets the roots spread out in zero Gs. But it doesn't end there. Plants need air to breathe, but they don't move. On Earth, winds keep fresh air coming. In the space station, there is no wind.

SMITH: And it's not very healthy, so we have fans that draw in fresh cabin air.

BRUMFIEL: Finally, there's the issue of light. The space station is whipping around the Earth fast.

SMITH: Every 90 minutes is a new sunrise, so it's very different, you know, and for a plant, that would be extremely confusing.

BRUMFIEL: The Veggie team added some artificial lights to keep the orbiting lettuce on an Earthly schedule. The system took years for engineers to develop, but growing today's salad on the space station didn't take long at all.

SMITH: July 8 it started. Today is 33 days of growth, and the plants were just fantastic - I mean, big, large leaves.

BRUMFIEL: The lettuce was ready. The astronauts were hungry. And this morning, there was just one question left.

SMITH: We'd been wondering, the Veggie team, if they were going to do a teriyaki chicken wrap, if they were going to do salad dressing, if they had salad dressing.

(SOUNDBITE OF ARCHIVED RECORDING)

UNIDENTIFIED MAN #2: I've got some extra virgin olive oil and some Italian balsamic vinegar.

BRUMFIEL: The astronauts went with a simple dressing, and the space salad tasted out of this world.

(SOUNDBITE OF ARCHIVED RECORDING)

UNIDENTIFIED MAN #1: That's awesome.

UNIDENTIFIED MAN #2: Yep, tastes good.

UNIDENTIFIED MAN #1: Yeah. I have that (laughter).

UNIDENTIFIED MAN #2: Kind of like arugula.

BRUMFIEL: This lettuce could be just the tip of the iceberg. There's plans for cabbage, cherry tomatoes and even potatoes as we leaf into the final frontier.

(SOUNDBITE OF MUSIC)

BRUMFIEL: Geoff Brumfiel, NPR News. Transcript provided by NPR, Copyright NPR.

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