- [Emily] Observing a distant star is sort of like
looking back through time.
(light dramatic music)
there is something wild about being able to observe things
that have been happening millions of years
before things even started happening here on Earth.
(gears clicking)
It can tilt your perspective sometimes,
standing on the earth you suddenly feel
like you're maybe looking down into the universe,
or that you can almost feel the earth turning,
it gives you this wonderful momentary sense of vertigo
when you realize just how big what you're looking at is
and how tiny we are.
- [Narrator] When a really big star dies,
it often goes out with a bang.
(bass thud)
They explode into luminous supernovas,
or collapse into black holes so dense
they swallow all light.
And here on Earth, Emily Levesque is watching them.
- [Emily] We can look at stars that you see in the night sky
with your naked eye.
A lot of those stars are thousands of light years away,
and the light that your eyes will be picking up
was originally emitted from the star thousands of years ago.
We're getting a peek into what was happening
an incredibly long time ago in the universe.
So these are stars that are much more massive
than our sun, at least eight times the mass of our sun,
and because they're so massive, they follow the sort of
live fast, die young philosophy, where they will live
for only 10 million years, our sun will live for 10 billion.
(light music)
I'm interested in those sort of late steps
of the star's evolution, before they actually die.
- [Narrator] A star begins life as a cloud
of condensed gas and dust molecules.
As it grows, the core begins to fuse hydrogen atoms,
generating so much heat and light,
that it shines brightly in the night sky.
But eventually, a star will run out of fuel.
(bass thud)
When this happens, it can collapse in less than a second.
Those final moments are what gets Emily so excited.
- I loved the idea that within all of that,
there were these bizarre, kind of scary,
kind of mysterious objects that not even light
could escape from, that stars might turn into one day,
that would do all these strange things
to have space and time warped.
(keyboard clicks)
I think one of the hard parts about astronomy
as compared to many other fields is,
we are really not able to touch or poke
whatever it is that we are studying.
We can't do an experiment, we can't say,
"Let's go blow up a star and see what happens."
So we'll go to these big, beautiful telescopes
all over the world.
We're just left observing them and then trying
to reproduce or reassemble what we think happened.
- [Narrator] Astronomers don't actually spend
as much time using telescopes as you might think.
Instead, they use computers to collect data,
and instruments like spectrographs,
that can map the life cycle of a star,
by analyzing the colors of light it emits.
But Emily does have access
to some of the most powerful telescopes in the world,
where she can get up close and personal with the universe.
- [Emily] Stepping out in the middle of the night
and seeing the sky is almost beyond description,
and I remember going down to Las Campanas Observatory
in northern Chile, and looking up at the southern sky,
and seeing just this ocean of stars.
It almost felt like there were more stars
just beyond what my eyes could see
that were like winking in and out of being visible,
and seeing the Milky Way just spread across the sky
is indescribable, it's so shockingly bright.
- [Narrator] By looking deep into the life cycle of stars,
Emily is hoping to do much more than just understand
how they begin or end.
In watching their transformation, she's hoping she can
bring us closer to understanding
how our entire universe works.
- [Emily] Everybody is in this field out of love
and out of passion for the universe.
I think it gets more beautiful,
because we understand it and because we study it.
I can look at a red star, and realize,
"I know why it's red, and I know why it looks that bright,
"and I know why these stars are twinkling the way they are."
And there's also this thrill of, this is what I do.
This is what I am studying and trying to explain.