Lifeboat Foundation

One of the world’s largest petawatt laser facility, LFEX, located in the Institute of Laser Engineering at Osaka University. Credit: Osaka University.

Laser Engineering at Osaka University have successfully used short, but extremely powerful laser blasts to generate magnetic field reconnection inside a plasma. This work may lead to a more complete theory of X-ray emission from astronomical objects like black holes.

In addition to being subjected to extreme gravitational forces, matter being devoured by a black hole can be also be pummeled by intense heat and magnetic fields. Plasmas, a fourth state of matter hotter than solids, liquids, or gasses, are made of electrically charged protons and electrons that have too much energy to form neutral atoms. Instead, they bounce frantically in response to magnetic fields. Within a plasma, magnetic reconnection is a process in which twisted magnetic field lines suddenly “snap” and cancel each other, resulting in the rapid conversion of magnetic energy into particle kinetic energy. In stars, including our sun, reconnection is responsible for much of the coronal activity, such as solar flares. Owing to the strong acceleration, the charged particles in the black hole’s accretion disk emit their own light, usually in the X-ray region of the spectrum.

The most massive black hole collision ever detected has been directly observed by the LIGO and VIRGO Scientific Collaboration, which includes scientists from The Australian National University (ANU).

The short gravitational wave signal, GW190521, captured by the LIGO and Virgo gravitational wave observatories in the United States and Europe on May 21 last year, came from two highly spinning, mammoth black holes weighing in at a massive 85 times and 66 times the mass of the Sun, respectively.

But that is not the only reason this system is very special. The larger of the two black holes is considered “impossible.” Astronomers predict that stars between 65 – 130 times the mass of the Sun undergo a process called pair instability, resulting in the star being blown apart, leaving nothing behind.

The cosmos was born in a churning fluid 300 million times hotter than the sun. We’ve recreated this hell, and it’s not just hot, it is also very, very strange, says Amanda Gefter (science writer based in London). TO LOOK deep into the fundamental structure of matter is to look billions of years back in time, to the moment when matter first blinked into being. Recreating the conditions of that moment has long been an aim for physicists wanting to understand how the universe evolved from the cosmic fireball that existed a fraction of a second after the big bang. Now researchers at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in Upton, New York, have, almost certainly, finally recreated the moments after creation. By colliding nuclei together at enormous speeds, RHIC experimenters were able to break down the structure of nuclear matter. This resulted, most experts agree, in the formation of a long-sought-after plasma that is believed to be the primal stuff of the cosmos, the state of matter at the beginning of time. It turns out, though, that the nature of matter is inextricably tied to the vacuum in which it resides. And the RHIC experiments have thrown up some surprises. They seem to show that the vacuum is a richer and more complicated place than was previously imagined. They suggest the boundary between something and nothing is more blurred than experts had predicted. The stuff made at RHIC is a plasma consisting of quarks and gluons, the most basic building blocks of everything we see around us. Quarks combine in threes to form the protons and neutrons that comprise the nucleus of every atom. But while we can observe a single proton or neutron, we cannot observe a single quark. Quarks are perpetually confined to group living. In fact, the harder you try to pull quarks apart, the stronger the force between them becomes. This is part of the theory of quantum chromodynamics (QCD), which describes how the force between the quarks is carried by the massless gluons.

In QCD, it is the vacuum that imprisons the quarks. While it may sound like a barren place, the vacuum of QCD is a complex, dynamic arena. It writhes with virtual particles that appear in pairs, then annihilate and disappear again. It is haunted by strange creatures of various kinds, too, topologically complex knots and twists that are relatives of wormholes, places where space turns in on itself and seems treacherous. These knots and twists carve out paths for the gluons to travel along, thereby keeping the quarks together. These strange ideas have credence because of the success of QCD in predicting the reactions of fundamental particles. The only way to unglue quarks is to “melt” the vacuum between them. But the vacuum doesn’t give in easily. To raze its jagged terrain requires enormous amounts of concentrated energy, found only in powerful nuclear collisions, or the fireball at the earliest moments of time.

Space is truly wild.

A merger with a black hole possessing an unexplained ‘forbidden mass’ created the first conclusive example of an intermediate black hole in the most massive merger ever detected using ripples in spacetime.

What Happens When a White Hole and a Black Hole Collide? 🕳️😀👌.

The blue and orange stars of the faint galaxy named NGC 2188 sparkle in this image taken with the NASA/ESA Hubble Space Telescope. Although NGC 2188 appears at first glance to consist solely of a narrow band of stars, it is classified by astronomers as a barred spiral galaxy. It appears this way from our viewpoint on Earth as the center and spiral arms of the galaxy are tilted away from us, with only the very narrow outer edge of the galaxy’s disk visible to us. Astronomers liken this occurrence to turning a dinner plate in your hands so you see only its outer edge. The true shape of the galaxy was identified by studying the distribution of the stars in the inner central bulge and outer disk and by observing the stars’ colors.

NGC 2188 is estimated to be just half the size of our Milky Way, at 50,000 light-years across, and it is situated in the constellation of Columba (the Dove). Named in the late 1500s after Noah’s dove in biblical stories, the small constellation consists of many faint yet beautiful stars and astronomical objects.

Text credit: ESA (European Space Agency) Image credit: ESA/Hubble & NASA, R. Tully.

The detectors have sensed dozens of such cataclysms over the past 5 years, but the one on 21 May 2019 was different. Not only was it the most powerful and distant merger ever seen, but the resulting black hole also belongs to a class of long-sought middleweight black holes, members of the LIGO-Virgo collaboration report today in two new studies. Puzzlingly, however, the two black holes that merged are heavier than expected: Their masses fall in a gap in which theorists … See More.

Black holes can expel a thousand times more matter than they capture. The mechanism that governs both ejection and capture is the accretion disk, a vast mass of gas and dust spiraling around the black hole at extremely high speeds. The disk is hot and emits light as well as other forms of electromagnetic radiation. Part of the orbiting matter is pulled toward the center and disappears behind the event horizon, the threshold beyond which neither matter nor light can escape. Another, much larger, part is pushed further out by the pressure of the radiation emitted by the disk itself.

Every galaxy is thought to have a supermassive black hole at its center, but not all galaxies have, or still have, accretion disks. Those that do are known as active galaxies, on account of their active galactic nuclei. The traditional model posits two phases in the matter that accumulates in the central region of an active galaxy: a high-speed ionized gas outflow of matter ejected by the nucleus, and slower molecules that may flow into the nucleus.

A new model that integrates the two phases into a single scenario has now been put forward by Daniel May, a postdoctoral researcher in the University of São Paulo’s Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG-USP) in Brazil. “We found that the molecular phase, which appears to have completely different dynamics from the ionized phase, is also part of the outflow. This means there’s far more matter being blown away from the center, and the active galactic nucleus plays a much more important role in the structuring of the galaxy as a whole,” May told Agência FAPESP.