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Nov 14, 2019

Ejected Star: How fast is fast?

Posted by in categories: astronomy, science, space
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

Sep 7, 2019

Stunning 1st image of Black Hole

Posted by in categories: astronomy, general relativity, gravity, physics, science, space
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.

Continue reading “Stunning 1st image of Black Hole” »

Aug 11, 2015

Slow death of Universe confirmed with precision

Posted by in categories: astronomy, cosmology, gravity, physics, space
  • 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 CNN.com]…

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.

Continue reading “Slow death of Universe confirmed with precision” »