Lifeboat Foundation

Are black holes bald or hairy? It all depends on the details of a fleeting gravitational wave.

They were spotted in the act of merging in a galaxy a billion light years away.

A NASA satellite searching space for new planets gave astronomers an unexpected glimpse at a black hole ripping a star to shreds.

It is one of the most detailed looks yet at the phenomenon, called a tidal disruption event (or TDE), and the first for NASA’s Transiting Exoplanet Survey Satellite (more commonly called TESS.)

The milestone was reached with the help of a worldwide network of robotic telescopes headquartered at The Ohio State University called ASAS-SN (All-Sky Automated Survey for Supernovae). Astronomers from the Carnegie Observatories, Ohio State and others published their findings today in The Astrophysical Journal.

https://www.youtube.com/watch?v=s78hvV3QLUE

Leonard Susskind is a professor of theoretical physics at Stanford University, and founding director of the Stanford Institute for Theoretical Physics. He is widely regarded as one of the fathers of string theory and in general as one of the greatest physicists of our time both as a researcher and an educator. This conversation is part of the Artificial Intelligence podcast.

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NASA has released a stunning image of three black holes about to collide with each other.

The ultra-rare is the best evidence yet of a so-called “triple system” – three active supermassive black holes smashing in to each other.

Each of the black holes is at the centre of its own galaxy.

DARK MATTER has long eluded our understanding but scientists searching for evidence of new physics capable of explaining such enduring mysteries of the Universe may have moved one step closer, following the latest CERN research.

In a mind-bending new paper, researchers suggest that there could be black holes orbiting the Sun, out past Pluto.

Scientists have long speculated that a “planet 9,” in orbit very far from the Sun, could explain why other bodies in our solar system have strange, hard-to-explain orbits.

Now, a pair of astrophysicists are suggesting a strange twist on that idea: that a black hole — or even a number of them — could be orbiting our Sun right now, way beyond Neptune.

Continue reading “Astrophysicists: There May Be Black Holes Orbiting Our Sun” »

Hidden deep in a basement at Stanford stands a 10-meter-tall tube, wrapped in a metal cage and draped in wires. A barrier separates it from the main room, beyond which the cylinder spans three stories to an apparatus holding ultra-cold atoms ready to shoot upward. Tables stocked with lasers to fire at the atoms—and analyze how they respond to forces such as gravity—fill the rest of the laboratory.

The tube is an atom interferometer, a custom-built device designed to study the wave nature of atoms. According to quantum mechanics, atoms exist simultaneously as particles and waves. The Stanford instrument represents a model for an ambitious new instrument ten times its size that could be deployed to detect gravitational waves—minute ripples in spacetime created by energy dissipating from moving astronomical objects. The instrument also could shed light on another mystery of the universe: dark matter.

Stanford experimental physicists Jason Hogan and Mark Kasevich never intended for their device to be implemented this way. When Hogan began his graduate studies in Kasevich’s lab, he focused instead on testing gravity’s effects on atoms. But conversations with theoretical physicist Savas Dimopoulos, a professor of physics, and his graduate students—often lured downstairs by an espresso machine housed directly across the hall from Kasevich’s office—led them to start thinking about its utility as a highly sensitive detector.

This new visualization of a black hole illustrates how its gravity distorts our view, warping its surroundings as if seen in a carnival mirror. The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole’s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance.

Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk.

Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein’s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight.