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The fastest man-made object pales in comparison to a Hills ejection

Earlier today, Genevieve O’Hagan updated Lifeboat readers on this week’s momentous event in Astronomy. At least, I find it fascinating—and so, I wish to add perspective…

30 years ago, astronomer Jack Hills demonstrated the math behind what has become known as the “Hills Mechanism”. Until this week, the event that he described had never been observed.* But his peer astronomers agreed that the physics and math should make it possible…

Hills explained that under these conditions, a star might be accelerated to incredible speeds — and might be even flung out of its galaxy:

  • Suppose that a binary star passes close to a black hole, like the one at the center of our galaxy
  • The pair of self-orbiting stars is caught up in the gravity well of a black hole, but not sucked in

If conditions are right, one star ends up orbiting the back hole while the other is jettisoned at incredible speed, yet holding onto its mass and shape. All that energy comes from the gravity of the black hole and the former momentum of the captured star. [20 sec animation] [continue below]

This week, astronomers found clear evidence of this amazing event and traced it back to our galactic center: Five million years ago — as our ancestors learned to walk upright — a star that passed close to the massive black hole at The Milky Way center was flung away at a staggering 6 million Kmh. It is traveling so fast, that it is no longer bound to our galaxy or galactic cluster. It is headed out of the galaxy.

  • Rifle Bullet: Can exceed Mach 3 (2,300 mph)
  • Apollo Rocket: Reached 25,000 mph; Earth escape velocity.
  • Juno Probe: 165,000 mph, a record prior to 2019. (It used Jupiter’s gravity to accelerate)
  • Parker Probe: 213,000 mph (Nov 2019), but will soon reach 430,000 in a tight arc around the Sun

* Prior to this week, astronomers have observed a few stars traveling inexplicably at incredible speeds. But this is the first time, that they have traced the trajectory back to a black hole and the conditions described by Jack Hills.


Eight of 347 scientists: Their achievement is above the fold in major newspapers

Yesterday (Sep 5, 2019), the Breakthrough Prize Foundation awarded $21.6 million US dollars to the scientists behind a stunning achievement. They imaged a black hole. Although the image was announced and released 5 months ago, the story is still unfolding.

Yesterday (Sep 5, 2019), the Breakthrough Prize Foundation awarded $21.6 million US dollars to the scientists behind a stunning achievement. They imaged a black hole. Although the image was announced and released 5 months ago, the story is still unfolding.

The Breakthrough Prize is funded by Russian-Israeli billionaire Yuri Milner. It is the highest-paying science prize for researchers in life science, math, and physics.

There are many black holes in our galaxy and some small ones in our own galactic “neighborhood” . Yet the EHT team* focused on M87, a black hole in the center of another Galaxy, 55 million light years from our solar system.

This is pretty far, but it is a massive black hole with a bright accretion disk (stuff around the event horizon), and it is orthogonal to our vantage point. How big is the M87 black hole? It is bigger than our entire solar system!

At this unfathomable distance, it is difficult to image anything smaller than an entire galaxy. But by combining data from instruments and math teams around the world, scientists released in April an actual photograph. To be precise, it is the shadow of a black hole, but it clearly shows the accretion disk, event horizon and a hole in the middle. In fact, it shows a perfect, glowing donut.

* The EHT = Event Horizon Telescope

To achieve the implausible, scientists combined data from 8 radio telescopes around the world, including two operated by the European Southern Observatory in Chile (producer of the first video, below). Although data was captured as radio waves, a team of 347 scientists pieced the information together into an actual image. What you see in the paragraph above is not an illustration based on data. It is a genuine photograph.

As you view the 1st video below, you may not feel that it is new. Even with the Big Bang in question, black holes are certain fact, and images have been circulating for years. But—until now—those were all artist’s renderings. There has never been an actual photo of a black hole. This is a first.

A web search turns up many videos about the achievement. Some are less than 2 minutes, and some are 2 hour documentaries. I like these two videos: [1] a 17 minute video documenting the effort to achieve this milestone and clearly explaining the result—and [2] an 11½ minute Ted Talk:

1. In the Shadow of the Black Hole

2. Inside the Black Hole That Made History

Philip Raymond co-chairs CRYPSA, hosts the Bitcoin Event and is keynote speaker at Cryptocurrency Conferences. He is a top writer at Quora.

  • The universe radiates only half as much energy as 2 billion years ago
  • New findings establish cosmos’ decline with unprecedented precision

From CNN
—The universe came in with the biggest bang ever. But now, with a drooping fizzle, it is in its swan song. The conclusion of a new astronomical study pulls no punches on this: “The Universe is slowly dying,” it reads.

Astronomers have believed as much for years, but the new findings establish the cosmos’ decline with unprecedented precision. An international team of 100 scientists used data from the world’s most powerful telescopes — based on land and in space — to study energy coming from more than 200,000 galaxies in a large sliver of the observable universe. [Full story below or at]…

Based on those observations, they have confirmed the cosmos is radiating only half as much energy as it was 2 billion years ago. The astronomers published their study on Monday on the website of the European Southern Observatory.

Analysis across many wavelengths shows the universe's electromagnetic energy output is dropping.The team checked the energy across a broad spectrum of lightwaves and other electromagnetic radiation and says it is fading through all wavelengths, from ultraviolet to far infrared.

Analysis across many wavelengths shows the universe’s electromagnetic energy output is dropping.

‘A cold, dark and desolate place’

At the ripe old age of nearly 13.8 billion years, the universe has arrived in its sunset years.

“The universe has basically sat down on the sofa, pulled up a blanket and is about to nod off for an eternal doze,” said astronomer Simon Driver, who led the team.

Death does not mean the universe will go away. It will still be there, but its stars and all else that produces light and stellar fire will fizzle out.

“It will just grow old forever, slowly converting less and less mass into energy as billions of years pass by until eventually, it will become a cold, dark and desolate place, where all of the lights go out,” said astronomer Luke Davies.

But don’t cry for the universe anytime soon. Astrophysicists say this will take trillions of years.

Bursting with energy

Go all the way back to its birth, and you find a vast contrast. In an infinitesimal fraction of a second, our entire cosmos blasted into existence in the Big Bang.

And the totality of the energy and mass in the universe originates from that moment, astronomers say.

Since that natal explosion, the cosmos has generated other sources of brilliant radiation — most notably stars — by converting some of the mass into energy when extreme gravity causes matter to burst into nuclear fusion.

But the universe is speckled by radiance from seething gas clouds, supernovas and, most spectacularly, the discs of hot matter that rotate around black holes to form quasars, which can be as bright as whole galaxies.

“While most of the energy sloshing around in the universe arose in the aftermath of the Big Bang, additional energy is constantly being generated by stars as they fuse elements like hydrogen and helium together,” Driver said.

Fizzling into space

The size and number of those sources of radiation so boggle the mind that it might be hard to imagine that the entirety of that vividness appears to be fading, as its energy flies off through space.

“This new energy is either absorbed by dust as it travels through the host galaxy, or escapes into intergalactic space and travels until it hits something, such as another star, a planet, or, very occasionally, a telescope mirror,” Driver said.

His team observed it from seven of the world’s mammoth telescopes spread out between Australia, the United States, Chile and Earth’s orbit. Many of the instruments specialize in receiving certain wavelengths of light and other electromagnetic waves.

Compiling the data from the collective wavelengths gives the scientists a more complete picture from across a broad spectrum of energy.

Their findings on the universe’s energy slump were part of the larger Galaxy And Mass Assembly, or GAMA, project to study how galaxies are formed. It has mapped out the position of 4 million galaxies so far.