Over the last two decades,
scientists have found thousands of planets elsewhere in the universe.
These are called exoplanets.
As we get better and better at finding them,
we need ways to narrow down the ones most likely to support life.
Two NASA rocket teams are working to do just that from Australia.
Their mission? Study a special pair of stars best seen in the Southern Hemisphere –
and propel humanity’s search for habitable worlds into the future.
I’m Miles Hatfield and I’m following these rocket teams to Australia
to show you what it takes to launch a rocket
and make groundbreaking scientific measurements.
Hang on tight – we’re going on an adventure High Above Down Under!
Earth is packed with life!
But some environments are more habitable than others.
So what makes an environment – or a planet – a good place for life to thrive?
Well, one thing is…
Water! And in fact,
that's what the search for life elsewhere in the universe has focused on so far,
finding planets where water can exist in liquid form.
There’s a region around every star that scientists call the goldilocks zone.
A planet in this zone has the right temperature for water to remain liquid.
Too close, and the water will evaporate away.
Too far, and it will freeze.
The distance has to be just right.
This zone has been the basis for the search for habitable worlds.
But just because a planet is inside the goldilocks zone, doesn’t mean it can sustain life.
Take for example the closest known exoplanet to Earth
at just 4.2 light-years away.
It’s located in the goldilocks zone,
but scientists think the star’s frequent eruptions
might have blown away any atmosphere the planet might’ve had.
In other words, the goldilocks zone is just a first guess.
To truly tell whether an exoplanet is habitable,
we need to look at the star it’s orbiting.
Unfortunately we can’t just observe a planet and understand it at face value.
We have to understand it in the context of what its parent star is giving it.
So scientists have been collecting data from different types of stars to learn how they affect their planets.
We would like to be able to create a menu of
star-planet possibilities that our future missions can draw from
and prioritize the most promising places to find habitable environments.
The next item to be added to the menu?
Yellow stars.
We’re looking for something around five billion years old, an average size…
Wait a second, don’t we have one right here?
So why not use the Sun?
We thought that our Sun is the prototype for kind of five-billion-year-old average yellow stars.
What we've learned recently is that
our Sun is actually quite inactive for a five-billion-year-old yellow star.
Typical earthling behavior, really –
thinking we’re the example for the entire universe.
But it turns out yellow stars are found throughout our galaxy,
and they tend to erupt with life-altering activity more often than our Sun does.
So, If we want to understand if they can still support life,
we’ll need more data than our Sun can give us.
That’s why two rocket teams are looking to Alpha Centauri A and B.
The reason why we're targeting Alpha Centauri is that it's our nearest solar twin.
So in many, many ways, it's just like the Sun.
It has almost the same mass, it's a very similar age.
And it's nearby, which is always great.
And with the help of NASA sounding rockets, they’ll capture light from those stars that doesn’t make it to the ground.
This range of highly energetic ultraviolet light has never been measured before for these stars.
Even small differences in this UV light from a star
can determine whether a nearby planet can support life, or not.
But the Alpha Centauri system isn't visible from most places in the U.S.
It’s best studied from the Southern Hemisphere.
That’s why we’re here in northern Australia
in the traditional homeland of the Yolngu people.
They’ve been observing the stars here for tens of thousands of years.
I’m here with two rocket science teams, SISTINE and DEUCE,
and a crew of about fifty NASA engineers, rocket specialists, and support staff.
In partnership with Equatorial Launch Australia and the Gumatj Corporation,
they’ve created an entire rocket range from scratch
to help the scientists achieve their goals.
In this series, you’re going to meet these teams and follow their quest,
high above the Australian outback to see what it takes
to make these first-ever measurements from our closest stellar neighbors.
We’re going behind the scenes to learn more about the science of habitability
and what goes into launching a rocket –
dodging venomous snakes and crocodiles along the way.
But first, we’ll take a look at how this brand new rocket range came to life
with the help of the Yolngu people who have been observing these stars for millenia.
Heliophysics Big Year.