Lifeboat Foundation

Capturing details of faraway members of our universe is an understandably complicated affair, but translating these details into the stunning space images that we see from space agencies around the world is equally difficult. It is here that supercomputers step in, helping process the massive amounts of data that are captured by terrestrial and space telescopes. On August 11, that is exactly what Australia’s upcoming supercomputer, called Setonix, helped achieve.

As its first project, Setonix processed the image of a dying supernova — the last stages of a dying star — from data sent to it by the Australian Square Kilometer Array Pathfinder (Askap). The latter is a terrestrial radio telescope, which has 36 individual antennas working together to capture radio frequency data about objects that are far away in space.

Such data contains intricate details about the object being observed. This not only increases the volume of the data being captured by the telescope, but also puts increasing pressure on a supercomputer to process it into a composite image.

Verse Uni This sometimes comes up: Could the universe have always existed? The problem is, if the universe had existed for an infinite amount of time, everything that could possibly happen must already have happened an infinite number of times — including that … See more.

In cosmology, the steady-state model is an alternative to the Big Bang theory of evolution of the universe. In the steady-state model, the density of matter in the expanding universe remains unchanged due to a continuous creation of matter, thus adhering to the perfect cosmological principle, a principle that asserts that the observable universe is practically the same at any time and any place.

From the smallest bacterium to the greatest galaxy, death looms on the horizon; even if, in cosmic terms, the time scales are too large for us to truly comprehend. Eventually, even the Universe itself should come to an end – when the last light winks out, and the cold, dense lumps of dead stars are all that remain.

That is, at least, how it is under current cosmological models. What if our Universe doesn’t die a cold death, but collapses, reinflates, and collapses again, over and over, like a giant cosmic lung?

It’s not exactly a widely accepted theory, but for some cosmologists, our Universe could be just one in a long series of births, deaths and rebirths that is without beginning or end – not a Big Bang, but a Big Bounce.

Webb was expected to merely confirm the Standard Model of the universe but its images are “surprisingly smooth, surprisingly small and surprisingly old.”

Using a magnetically stirred liquid metal, researchers have reproduced a key feature of astrophysical accretion disks: a turbulence-based transfer of angular momentum.

Astrophysical disks are ubiquitous objects in the cosmic landscape: we observe them around matter-gobbling black holes and planet-forming stellar systems. The gas and dust in these disks slowly drift inward and eventually reach the central star or black hole. The energy released in this accretion process makes some of these disks very luminous. However, the physical mechanism responsible for this accretion remains elusive despite 40 years of active research. Now Marlone Vernet from Sorbonne University in France and his colleagues model astrophysical disks with an experimental system based on a rotating disk of liquid metal [1]. The novelty in this experiment is that the disk is set into rotation thanks to electrical currents and magnetic fields in a way that mimics gravity. The experiment provides strong evidence of angular momentum transport, which is thought to be a key feature in astrophysical accretion.

Astronomers have long sought the launch sites for some of the highest-energy protons in our galaxy. Now a study using 12 years of data from NASA’s Fermi Gamma-ray Space Telescope confirms that one supernova remnant is just such a place.

Fermi has shown that the shock waves of exploded stars boost particles to speeds comparable to that of light. Called cosmic rays, these particles mostly take the form of protons, but can include atomic nuclei and electrons. Because they all carry an electric charge, their paths become scrambled as they whisk through our galaxy’s magnetic field. Since we can no longer tell which direction they originated from, this masks their birthplace. But when these particles collide with interstellar gas near the supernova remnant, they produce a telltale glow in gamma rays—the highest-energy light there is.

Continue reading “NASA’s Fermi telescope confirms star wreck as source of extreme cosmic particles” »

Stephen Hawking’s suggestion that black holes “leak” radiation left physicists with a problem they have been attempting to solve for 51 years.

In what is arguably his most significant contribution to science, Stephen Hawking suggested that black holes can leak a form of radiation that causes them to gradually ebb away, and eventually end their lives in a massive explosive event.

This radiation 0, later called “Hawking radiation,” inadvertently causes a problem at the intersection of general relativity and quantum physics — the former being the best description we have of gravity and the universe on cosmically massive scales, while the latter is the most robust model of the physics that governs the very small.

Continue reading “What Happens When Black Holes Die?” »

To form a celestial object, start with a gas cloud and add gravity. Then, it gets complicated.

Accretion is one of the most fundamental processes in the cosmos. It is a universal phenomenon triggered by gravity, and the process by which bits of matter accumulate and coalesce with more bits of matter. It works inexorably on all scales to attract and affix smaller things to bigger things, from the tiniest dust grains to supermassive black holes.

Accretion creates everything there is: galaxies, stars, planets, and eventually, us. It is the reason the universe is filled with a whole bunch of somethings instead of a whole lot of nothing.

Continue reading “The physics of accretion: How the universe pulled itself together” »