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Over the last two decades,

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scientists have found thousands of planets elsewhere in the universe.

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These are called exoplanets.

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As we get better and better at finding them,

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we need ways to narrow down the ones most likely to support life.

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Two NASA rocket teams are working to do just that from Australia.

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Their mission? Study a special pair of stars best seen in the Southern Hemisphere –

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and propel humanity’s search for habitable worlds into the future.

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I’m Miles Hatfield and I’m following these rocket teams to Australia

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to show you what it takes to launch a rocket

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and make groundbreaking scientific measurements.

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Hang on tight – we’re going on an adventure High Above Down Under!

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Earth is packed with life!

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But some environments are more habitable than others.

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So what makes an environment – or a planet – a good place for life to thrive?

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Well, one thing is…

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Water! And in fact,

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that's what the search for life elsewhere in the universe has focused on so far,

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trying to find places where water can exist in liquid form.

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finding planets where water can exist in liquid form.

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There’s a region around every star that scientists call the goldilocks zone.

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A planet in this zone has the right temperature for water to remain liquid.

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Too close, and the water will evaporate away.

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Too far, and it will freeze.

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The distance has to be just right.

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This zone has been the basis for the search for habitable worlds.

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But just because a planet is inside the goldilocks zone, doesn’t mean it can sustain life.

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Take for example the closest known exoplanet to Earth

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at just 4.2 light-years away. 

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It’s located in the goldilocks zone,

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but scientists think the star’s frequent eruptions

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might have blown away any atmosphere the planet might’ve had.

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In other words, the goldilocks zone is just a first guess.

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To truly tell whether an exoplanet is habitable,

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we need to look at the star it’s orbiting. 

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Unfortunately we can’t just observe a planet and understand it at face value.

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We have to understand it in the context of what its parent star is giving it.

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So scientists have been collecting data from different types of stars to learn how they affect their planets.

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We would like to be able to create a menu of

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star-planet possibilities that our future missions can draw from

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and prioritize the most promising places to find habitable environments.

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The next item to be added to the menu?

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Yellow stars.

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We’re looking for something around five billion years old, an average size…

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Wait a second, don’t we have one right here?

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So why not use the Sun?

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We thought that our Sun is the prototype for kind of five-billion-year-old average yellow stars.

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What we've learned recently is that

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our Sun is actually quite inactive for a five-billion-year-old yellow star.

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Typical earthling behavior, really –

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thinking we’re the example for the entire universe. 

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But it turns out yellow stars are found throughout our galaxy,

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and they tend to erupt with life-altering activity more often than our Sun does. 

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So, If we want to understand if they can still support life,

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we’ll need more data than our Sun can give us.

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That’s why two rocket teams are looking to Alpha Centauri A and B.

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The reason why we're targeting Alpha Centauri is that it's our nearest solar twin.

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So in many, many ways, it's just like the Sun.

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It has almost the same mass, it's a very similar age.

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And it's nearby, which is always great.

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And with the help of NASA sounding rockets, they’ll capture light from those stars that doesn’t make it to the ground.

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This range of highly energetic ultraviolet light has never been measured before for these stars.

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Even small differences in this UV light from a star

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can determine whether a nearby planet can support life, or not.

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But the Alpha Centauri system isn't visible from most places in the U.S.

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It’s best studied from the Southern Hemisphere.

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That’s why we’re here in northern Australia

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in the traditional homeland of the Yolngu people.

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They’ve been observing the stars here for tens of thousands of years.

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I’m here with two rocket science teams, SISTINE and DEUCE,

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and a crew of about fifty NASA engineers, rocket specialists, and support staff. 

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In partnership with Equatorial Launch Australia and the Gumatj Corporation,

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they’ve created an entire rocket range from scratch

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to help the scientists achieve their goals.

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In this series, you’re going to meet these teams and follow their quest,

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high above the Australian outback to see what it takes

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to make these first-ever measurements from our closest stellar neighbors.

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We’re going behind the scenes to learn more about the science of habitability

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and what goes into launching a rocket –

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dodging venomous snakes and crocodiles along the way.

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But first, we’ll take a look at how this brand new rocket range came to life

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with the help of the Yolngu people who have been observing these stars for millenia.

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Heliophysics Big Year.