Cygnus X-1

Okay, now let's get back to our dark star.

This is Cygnus X-1.

It's about 7,200 light-years away from Earth, a stellar-mass black hole approximately 20 times the mass of the sun formed from the collapse of a gigantic star.

It's one half of a high-mass X-ray binary system sitting right beside a supergiant star.

They could be any size, little tiny ones with less mass than a staple or up to 100,000 times more massive than the sun.

The littlest guys would have all been lost to Hawking radiation in the 14 billion years since the universe began, but there are plenty of others that could still be flying around, even potentially just out past Pluto.

Okay, next up mass-wise are the stellar-mass black holes that we all know and love, like Gaia BH1 or Cygnus X-1.

They land right around 5 to 20 times the mass of our sun.

At such extreme temperatures, the material emits intense X-rays detectable from Earth.

The first confirmed black hole, discovered in 1971, exists in such a binary system called Cygnus X-1.

The companion star, a brilliant blue supergiant, is orbited by an invisible black hole containing several times the Sun's mass.

The companion star orbits the black hole in about five and a half days.

Data from each telescope is recorded with nanosecond timing accuracy.

Later, computers process and combine the data to construct images of astonishing detail.

Cygnus X-1's discovery and confirmation marked a watershed moment in black hole science.

In 1971, a rocket-borne X-ray detector discovered an intense source of X-rays at the location of a blue supergiant star known as HDE 226868.

Calculate that a large object would be enough, about 500 times our sun, for this to happen.

What would happen to the star then? If no light could escape it, wouldn't it become completely invisible, like a dark star? This is Cygnus X-1.

It is about 7,200 light-years from Earth, and it is a black hole of stellar mass equal to about 20 times the mass of the Sun, formed by the collapse of a giant star.

It is half of a high-mass X-ray binary system, positioned right next to a super-giant star.

But 1973, which was a big time in black hole research, as I understand it, as you might imagine from the fact that they found one and all agreed, yeah, that's what that is.

Cygnus X-1, very good sci-fi name.

Very much so, yes.

Cygnus, is it near the Swan constellation?

Yeah.

Or they think of Cygnus X-1 ripping gas off a companion star.

Or that iconic, terrifying, glowing orange ring from the Event Horizon Telescope image of M87.

We are deeply trained by sci-fi and pop science to think of an inescapable cosmic vacuum cleaner.

One of the brightest stars in the sky, Deneb, is found within the Cygnus constellation.

The constellation is also home to one of the biggest stars currently known, NML Cygni, or Cygnus X-1.

A far-off X-ray source with an undetected huge supergiant companion, and which was the first object that is widely believed to be a black hole, is likewise located in the constellation.

It was discovered that a star within Cygnus, Cygnus X3, has been giving off cosmic particle rays aimed directly at Earth, which is directly involved with our evolution on this planet.

in the history of life on Earth.

And so what makes us think that it's all over the universe? I would love it if it was all over the universe, that there was a Star Trek convention right now on Cygnus X-1.

You know what I mean? I think that would be just as cool as

shit.

But his solution researched the possibility of these dark stars, something considered implausible by Einstein and many others.

By 1971, the astronomical discovery of Cygnus X-1 provided the first evidence that this wasn't a trick of the math, but a real phenomenon.

A black hole, as physicist John Wheeler later dubbed them.

Of course, since then, we've accumulated a wealth of observational support for their existence, from...