00:00We already have Hubble. We already have James Webb. So why did NASA just launch a third giant
00:05telescope? Meet the Roman Space Telescope. And the answer begins with a question that haunts
00:11scientists. What is the universe actually made of? Hubble and Webb are precision instruments.
00:16They zoom in and study one galaxy in breathtaking detail. Roman works differently. Roman scans,
00:22staring at enormous swaths of the sky, again and again, to catch things that change. Because change
00:28is the key. Everything we can touch and see, every star, every planet, every atom of you and me,
00:33makes up only about 5% of the cosmos. Another 27% is dark matter. And 68%. Dark energy. We
00:42see their
00:42effects, but we have no idea what they are. Roman was built to find out. Dark matter doesn't emit
00:48light, but it has mass. And mass means gravity. When light from a distant galaxy passes near it,
00:54gravity bends that light. The galaxy looks slightly distorted. But is it really distorted?
01:00Looking at one galaxy, you can't tell. So Roman will observe hundreds of millions of them.
01:05With enough galaxies, those tiny repeated distortions reveal where the invisible mass is hiding.
01:11Now dark energy. The universe isn't just expanding, it's expanding faster and faster.
01:16Scientists call whatever drives this acceleration, dark energy. But that's just a name.
01:21So Roman will watch thousands of distant supernovae. Each has a known brightness.
01:27Measure how bright it looks, calculate how far away it is, and track how fast its galaxy is fleeing.
01:32That reveals how the universe's expansion has changed over time.
01:36Will Roman give us the final answer? Not necessarily.
01:40More likely, it will rule out theories that don't match the data.
01:43If nothing fits, scientists may have to question our understanding of gravity itself.
01:48And even without a perfect answer, knowing which explanations are wrong is real progress.
01:52It tells us where to look next.
01:55Roman will also hunt for planets.
01:57When a nearby star passes in front of a farther one, its gravity briefly magnifies the distant light.
02:02If that star has planets, the light flickers, a tiny signature of a hidden world.
02:07Roman could even find wandering planets, worlds with no star at all, flung out into the dark.
02:12Counting them reveals how planetary systems are born, change, and lose their worlds.
02:17Right now, Roman is cruising toward the L2 point, a million and a half kilometers from Earth.
02:22It will unfold, calibrate, and test itself over the coming months.
02:26NASA hopes to release its first images in 2027.
02:29It may not immediately reveal what dark matter and dark energy are.
02:33But it will bring back data we've never had, data that rules out the wrong ideas and points science toward
02:37the right ones.
02:38The launch pad has gone quiet.
02:41But the human search for the unknown has only just begun.
02:44Equals, equals, equals, equals, and equals, equals, equals.
02:46Equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
02:57equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
02:57equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
02:57equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
02:57equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
03:00equals, equals, equals, equals, equals, equals, equals, equals, equals, equals,
