(film projector whirring) (dramatic music) - [Narrator] More than 50 years have passed since a human walked on the moon.

Now we have our sights set on building a base there, and even pushing further out into the solar system.

- [Audience Member] Wow.

- [Narrator] But if we're going to have a successful long-term settlement somewhere other than our planet, we're going to need to grow our own food.

This means figuring out how to make life that evolved on Earth happy enough to thrive in space.

(rocket roars) And that's "All Science.

No Fiction."

(gentle music) (engine rumbling) - Oh, my god.

It's here.

(Yuliya laughs) (truck hisses) - [Narrator] It may just look like a couple trucks... - [Ryan] Morning.

- [Narrator] But for Ryan McClure and Yuliya Farris, the cargo inside, about a hundred test tubes of frozen soil from a farm in eastern Washington, has made an incredible journey.

- This has been three years in the making.

We sent those samples up to the International Space Station where they've had a three months' stay.

And now those samples are coming back down to Earth.

They're coming back home.

- [Narrator] The soil samples in these boxes contain much more than just soil.

There's millions of soil microbes, which these researchers believe are critical allies to have if we want to feed ourselves in space.

(gentle music) (gentle jazz music) (test tubes rattling) (engine rumbles) (rocket roars) (rocket screeches) (water splashes) (helicopter whirring) (engine rumbling) (tires screeching) ♪ The boxes are here ♪ - [Yuliya] This is me, first time touching it.

(Yuliya laughs) - [Narrator] The soil and microbe samples are delicate and the team's work has to start right away.

- [Yuliya] "Handle with extreme care."

(scissors rasping) - Where's Marci?

- Marci!

Let's go up and burst the cake!

(laughs) - Ready?

- Yeah.

(Ryan chuckles) - Okay.

Ooh.

- There they are.

The look the same.

- Our primary goal here is to understand how do interactions between different microbial species change when they're growing and cultured on the Earth versus when they're growing and cultured in the International Space Station.

- [Narrator] The microbes spent about three months on the ISS growing with higher carbon dioxide and radiation levels than on Earth, and in very low gravity.

The samples were frozen at different points to stop their activity, giving the scientists snapshots of how the microbial communities function and change over time.

(bag rustling) - So zero week, four weeks, eight weeks, or 12 weeks.

Looking at the yellow samples, these are eight weeks.

- [Narrator] But why do these researchers care so much about soil microbes?

Well, for the same reason we care about them on Earth.

- [Ryan] A lot of what the soil microbiome does here on Earth is really important.

- [Narrator] Our soil is alive, teeming with microorganisms that make compost, add nutrients, and make plants much happier, increasing crop yields.

- So if we want to take those benefits of the soil microbiome that we have here on Earth and start to transfer them up to other situations, other environments like the Space Station, an environment where growing plants might be really useful, we really need to understand the details of how these microbial species interact.

- [Narrator] There are more microbes in a teaspoon of soil than there are people on the planet, and their interactions are incredibly complex.

- They call it community.

So it's like humans: we all live and interact and share some resources with each other.

It's the same way on the microbial level.

- [Narrator] To get a clear picture of their interactions, the team had to simplify things.

(bell dings) This meant going from thousands of microbe species to just eight kinds of bacteria that are known to work together.

These are the true stars of the show.

- [Announcer] The following microbes are brought to you in living color on OPB.

Ensifer, Neorhizobium, Variovorax, Sphingopyxis, Sinorhizobium, Dyadobacter, Streptomyces, Rhodococcus, all in the microbial community.

- They all visually look different, they all smell different.

You know, and they all have, like, down to...

They have their own little key roles just even in, you know, acting as a community together.

It's like frozen, dry soil, so it's really hard to, like, separate it.

- [Narrator] The soil microbes in these tubes interact with each other in a variety of ways.

For example, some will break down a kind of carbon in the soil called chitin, and in turn produce byproducts that other microbes need.

- Mm.

(liquid splashes) Ah.

- [Narrator] But will the microbes be able to share those nutrients when there's no gravity?

McClure thinks yes.

- If two people are in a room and one of them wants to interact with the other by throwing a ball, under a condition of low gravity, that ball's for sure gonna get there.

It's just much easier to pass things to your partner or receive things from your partner.

And I'm wondering if that might be the same thing that we see with these microbial communities where nutrients and these chitin breakdown products are easier to share.

- [Narrator] To test this hypothesis, the researchers are looking at samples from several different angles.

- [Yuliya] First, it's a flow cell where all of the small amounts of sample gonna run through.

- [Narrator] They analyze DNA to figure out how the microbe populations change in space.

- It's gonna tell if they grew or not, or maybe they all died.

Who knows?

(laughs) But we hoping that did not happen, yeah.

- [Ryan] You can see this sort of orangey-yellow liquid at the top.

This is where our RNA is.

- [Narrator] They look at RNA and proteins, which gives them clues about what the microbes were doing.

- [Ryan] We need to get that RNA out of that solution and purified.

But you don't want to start pulling up the soil and stuff at the bottom.

- [Narrator] And they look at metabolites that show how the microbes are interacting with each other.

- It's when you merge these four puzzle pieces together that you can get the best view of the complete community.

- [Narrator] The data will start to reveal the best mix of microbes we should be harnessing to grow food in space.

- One day, we will be traveling to other planets, to different stations, and we can grow food that will be, you know, tasting just like it's growing on Earth.

It's, in some way, far off, but you give it another 10, 20 years and it will be not anymore far away.

(chuckles) - [Announcer] And liftoff.

- [Narrator] And when we finally make the jump to leave Earth behind, we may well be bringing soil microbes along for the ride.

- [Announcer] International Space Station with cool science.

(rocket roaring) (machine rumbling) - Sorry.

(laughs) Sorry.

- You want me to look in the camera, or you want me to look at the tube?

- [Crew Member] Look at the tube.

- [Narrator] OPB wouldn't be able to grow strong without its microbial, check that, its member support.

Thanks.

- It's so much easier just to do it with your phone.

- [Narrator] And don't miss out on any of OPB's great news coverage and cultural programs by subscribing to OPB Insider at opb.org/allscience.

- [Yuliya] Whoa, this is huge.

(Yuliya laughs) (no audio)