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It`s Okay To Be Smart, Seeing a Black Hole with a Planet-Sized Telescope | STELLAR

Seeing a Black Hole with a Planet-Sized Telescope | STELLAR

Thank you to Draper and its Hack the Moon initiative for supporting PBS Digital Studios.

Imagine for a moment that I'm a beam of light far outside the visible range, traveling

from a star in a distant part of the universe.

If you want to see where I came from, you'll need two things: a series of radio telescopes

like the Submillimeter Array behind me, and one of the most accurate clocks in the world.

I've traveled a long way to get here, so when I arrive on Earth I'm an extremely

faint signal. To see me you'll need to point multiple antennas at the same point in the

sky – antennas like these. But my faint signal will arrive at each telescope at ever

so slightly different points in time. Using our incredibly precise clock, we can synchronize

these signals and combine those faint images to make a much more vivid Joe.

And if you point enough radio telescopes at the exact same spot, and you have access to

a supercomputer, well, you can even see something we once thought was unseeable...a black hole.

On April 10, 2019, astrophysicists from the Event Horizon Telescope collaboration electrified

the world with the first ever image of a black hole.

This astronomical donut smothered in orange frosting is a supermassive black hole weighing

about 6.5 billion times the mass of our sun, at the center of the M87 galaxy, about 55

million light years away in the constellation Virgo.

The orange ring that we see are photons, produced by hot swirling gas orbiting around the edge

of the black hole. The inner edge of that ring is the event horizon, a precipice of no return.

The EHT is not just one telescope. It's many telescopes, including these here, working

together as a larger telescope, and it let us see something we used to think was impossible.

The idea of dark, massive objects in space, dense enough to capture light itself had been

hinted at by John Michell as far back as the 18th century. Objects that came to be called

“dark stars”. But the first modern hints about black holes arrived as an abstract mathematical

idea inside Einstein's theory of general relativity.

Over the 20th century scientists were looking for black holes, but how do you observe the

absence of light?

Creating an image of a light swallowing cosmic abyss is not unlike tuning in to hear your

favorite song on the radio. Except imagine this is your receiver.

Black Holes may not produce any light waves in the visible spectrum, but those hot clouds

of swirling gas at their edge produce light in other parts of the electromagnetic spectrum

that we can detect. But luckily, space is mostly transparent to radio waves, so that's

what the EHT team chose to look for.

But that gave astronomers one more problem to solve. Radio waves have very long wavelengths,

and the longer the wavelength of light you use, the more difficult it is to produce a

sharp image. Not to mention, as massive as black holes are, its very tiny in the sky.

From our vantage point on Earth, seeing M87* in the sky is like trying to see a bagel on

the moon.

The solution? A telescope the size of the Earth.

Geoff, it's so nice to meet you.

It's really great to have you here, Joe.

You have got to tell me how you used those things to take that awesome picture.

We are using with the Event Horizon Telescope, effectively, a telescope that has a resolution

a thousand times better than the Hubble Space Telescope.

The way you get finer and finer detail, better angular resolution out of telescopes

is you build a bigger diameter aperture.

So what we do is take telescopes that are located around the world, all radio

and we connect them together and we use them to build a single telescope

It's a mirror the size of the whole planet, but most of the mirror is missing.

In order to make that mirror, we have to have the clocks, between the telescopes, carefully aligned.

We can get our clock aligned to more than a picosecond.

A normal stopwatch goes out to like two places, maybe, and you're going

like eleven places beyond that

Exactly!

Over several nights in April 2017, EHT pointed telescopes at 8 different locations around

the world at the black hole, including the eight antennas here at the Submillimeter Array

on Mauna Kea. To act as one, they synchronized their observations using an extremely precise

clock at each site. This clock, called a hydrogen maser, can keep time to within a billionth

of a second.

Then by combining all the data in a supercomputer, they created the first ever radio image of

a black hole.

We're in a very big science room!

What happens in here?

So it's a big supercomputer, specially designed for the purpose of

combining the signals together from all of our different telescopes

and also, to take the combined signal, and format it in a way that we can use for the Event Horizon Telescope.

This is where you saved the black hole

Exactly, light stopped right here.

At the other end of this lab is where the clock signals come in, so the hydrogen maser

is in the bunker that's underneath here

in its concrete shell, and it sends up its reference tone

10 megahertz signal. And that signal gets distributed to all the different clocks that are used throughout the system.

We're interfering waves together, that's what interferometry means

and so if those waves move back and forth a little bit

when you interfere them they destructively interfere and you lose your signal.

We use GPS to timestamp it and then we use the hydrogen maser to make sure that on

the shortest time scales, everything's aligned just fine.

This is where our part of the EHT data comes in

and we record the light and it gets stopped forever.

But this isn't the end of our story. EHT is now trying to take a picture of the

supermassive black hole at the center of our very own galaxy

in the constellation Sagittarius.

Thanks to generations of scientists, we're long past using just our eyes to see

the universe.

With each new discovery, one mystery ends only to reveal ever greater mysteries

for new scientists to uncover, and to keep us all looking out at the stars in wonder.

If you thought a planet-sized telescope was big, just wait until you find out how big the universe is.

Check out Matt O'Dowd from Space Time on the next episode.

Thank you to Draper and their Hack the Moon initiative for supporting PBS Digital Studios.

You know the story of the astronauts that landed on the moon

now you can log on to wehackthemoon.com

to discover the story of the male and female engineers who guided them there and back safely.

Hack The Moon chronicles the engineers and technologies behind the Apollo missions

Brought to you by Draper, the site is full of images and videos and stories about the people who hacked the moon.

PBS is bringing you the universe with the SUMMER OF SPACE, which includes six incredible

new science and history shows airing on PBS and streaming on PBS.org and the PBS Video

app. Watch it all on PBS.org/summerofspace.

Seeing a Black Hole with a Planet-Sized Telescope | STELLAR Ein Schwarzes Loch mit einem Teleskop in Planetengröße sehen | STELLAR Ver un agujero negro con un telescopio del tamaño de un planeta | STELLAR Voir un trou noir avec un télescope de la taille d'une planète | STELLAR Vedere un buco nero con un telescopio di dimensioni planetarie | STELLAR 惑星サイズの望遠鏡でブラックホールを見る|STELLAR ステラー Een zwart gat zien met een telescoop ter grootte van een planeet | STELLAR Ver um buraco negro com um telescópio do tamanho de um planeta | STELLAR Наблюдение за черной дырой с помощью телескопа размером с планету | STELLAR Gezegen Boyutunda Bir Teleskopla Kara Delik Görmek | STELLAR Побачити чорну діру за допомогою телескопа розміром з планету | STELLAR 用行星大小的望遠鏡觀察黑洞|恆星

Thank you to Draper and its Hack the Moon initiative for supporting PBS Digital Studios.

Imagine for a moment that I'm a beam of light far outside the visible range, traveling

from a star in a distant part of the universe.

If you want to see where I came from, you'll need two things: a series of radio telescopes

like the Submillimeter Array behind me, and one of the most accurate clocks in the world. zoals de Submillimeter Array achter me, en een van de nauwkeurigste klokken ter wereld.

I've traveled a long way to get here, so when I arrive on Earth I'm an extremely

faint signal. To see me you'll need to point multiple antennas at the same point in the

sky – antennas like these. But my faint signal will arrive at each telescope at ever

so slightly different points in time. Using our incredibly precise clock, we can synchronize

these signals and combine those faint images to make a much more vivid Joe.

And if you point enough radio telescopes at the exact same spot, and you have access to

a supercomputer, well, you can even see something we once thought was unseeable...a black hole.

On April 10, 2019, astrophysicists from the Event Horizon Telescope collaboration electrified

the world with the first ever image of a black hole.

This astronomical donut smothered in orange frosting is a supermassive black hole weighing |||covered thickly with|||||||||

about 6.5 billion times the mass of our sun, at the center of the M87 galaxy, about 55

million light years away in the constellation Virgo.

The orange ring that we see are photons, produced by hot swirling gas orbiting around the edge

of the black hole. The inner edge of that ring is the event horizon, a precipice of no return.

The EHT is not just one telescope. It's many telescopes, including these here, working

together as a larger telescope, and it let us see something we used to think was impossible.

The idea of dark, massive objects in space, dense enough to capture light itself had been

hinted at by John Michell as far back as the 18th century. Objects that came to be called

“dark stars”. But the first modern hints about black holes arrived as an abstract mathematical

idea inside Einstein's theory of general relativity.

Over the 20th century scientists were looking for black holes, but how do you observe the

absence of light?

Creating an image of a light swallowing cosmic abyss is not unlike tuning in to hear your

favorite song on the radio. Except imagine this is your receiver.

Black Holes may not produce any light waves in the visible spectrum, but those hot clouds

of swirling gas at their edge produce light in other parts of the electromagnetic spectrum

that we can detect. But luckily, space is mostly transparent to radio waves, so that's

what the EHT team chose to look for.

But that gave astronomers one more problem to solve. Radio waves have very long wavelengths,

and the longer the wavelength of light you use, the more difficult it is to produce a

sharp image. Not to mention, as massive as black holes are, its very tiny in the sky.

From our vantage point on Earth, seeing M87* in the sky is like trying to see a bagel on |||||||||||||||||distant object|

the moon.

The solution? A telescope the size of the Earth.

Geoff, it's so nice to meet you.

It's really great to have you here, Joe.

You have got to tell me how you used those things to take that awesome picture.

We are using with the Event Horizon Telescope, effectively, a telescope that has a resolution

a thousand times better than the Hubble Space Telescope.

The way you get finer and finer detail, better angular resolution out of telescopes

is you build a bigger diameter aperture. ||||||opening or hole

So what we do is take telescopes that are located around the world, all radio

and we connect them together and we use them to build a single telescope

It's a mirror the size of the whole planet, but most of the mirror is missing.

In order to make that mirror, we have to have the clocks, between the telescopes, carefully aligned.

We can get our clock aligned to more than a picosecond. We kunnen onze klok op meer dan een picoseconde afstemmen.

A normal stopwatch goes out to like two places, maybe, and you're going

like eleven places beyond that

Exactly!

Over several nights in April 2017, EHT pointed telescopes at 8 different locations around

the world at the black hole, including the eight antennas here at the Submillimeter Array

on Mauna Kea. To act as one, they synchronized their observations using an extremely precise na Mauna Kea. Aby działać jako jeden, zsynchronizowali swoje obserwacje za pomocą niezwykle precyzyjnego

clock at each site. This clock, called a hydrogen maser, can keep time to within a billionth klok op elke locatie. Deze klok, een waterstofmaser genoemd, kan de tijd bijhouden tot op een miljardste

of a second.

Then by combining all the data in a supercomputer, they created the first ever radio image of

a black hole.

We're in a very big science room!

What happens in here?

So it's a big supercomputer, specially designed for the purpose of Więc jest to wielki superkomputer, specjalnie zaprojektowany do celów

combining the signals together from all of our different telescopes łącząc sygnały ze wszystkich naszych teleskopów.

and also, to take the combined signal, and format it in a way that we can use for the Event Horizon Telescope.

This is where you saved the black hole

Exactly, light stopped right here.

At the other end of this lab is where the clock signals come in, so the hydrogen maser |||||||||||||||||microwave amplification device

is in the bunker that's underneath here

in its concrete shell, and it sends up its reference tone

10 megahertz signal. And that signal gets distributed to all the different clocks that are used throughout the system. 10 megahertzów sygnału. Sygnał ten jest dystrybuowany do wszystkich zegarów używanych w całym systemie.

We're interfering waves together, that's what interferometry means

and so if those waves move back and forth a little bit

when you interfere them they destructively interfere and you lose your signal. wanneer je ze stoort, interfereren ze destructief en verlies je je signaal.

We use GPS to timestamp it and then we use the hydrogen maser to make sure that on We gebruiken GPS om het te tijdstempelen en dan gebruiken we de waterstofmaser om ervoor te zorgen dat aan

the shortest time scales, everything's aligned just fine. de kortste tijdschalen, alles is prima op elkaar afgestemd.

This is where our part of the EHT data comes in

and we record the light and it gets stopped forever.

But this isn't the end of our story. EHT is now trying to take a picture of the

supermassive black hole at the center of our very own galaxy superzwaar zwart gat in het centrum van ons eigen sterrenstelsel

in the constellation Sagittarius. ||star group|

Thanks to generations of scientists, we're long past using just our eyes to see

the universe.

With each new discovery, one mystery ends only to reveal ever greater mysteries

for new scientists to uncover, and to keep us all looking out at the stars in wonder.

If you thought a planet-sized telescope was big, just wait until you find out how big the universe is.

Check out Matt O'Dowd from Space Time on the next episode.

Thank you to Draper and their Hack the Moon initiative for supporting PBS Digital Studios.

You know the story of the astronauts that landed on the moon

now you can log on to wehackthemoon.com

to discover the story of the male and female engineers who guided them there and back safely.

Hack The Moon chronicles the engineers and technologies behind the Apollo missions

Brought to you by Draper, the site is full of images and videos and stories about the people who hacked the moon. |||||||||||||||||||explored ingeniously||

PBS is bringing you the universe with the SUMMER OF SPACE, which includes six incredible

new science and history shows airing on PBS and streaming on PBS.org and the PBS Video

app. Watch it all on PBS.org/summerofspace.