Artist impression of an X-ray binary system. This one is called MAXI J1820+070 containing a black hole (small black dot at the center of the gaseous disk) and a companion star. A narrow jet is directed along the black hole spin axis, which is strongly misaligned from the rotation axis of the orbit. Image produced with Binsim (credit: R. Hynes).
The planets in our Solar System all rotate on axes that roughly match the Sun’s rotational axis. This agreement between the axes of rotation is the typical arrangement in any system in space where smaller objects orbit a larger one.
But in one distant binary system, the large central object has an axis of rotation tilted about 40 degrees compared to its smaller satellite. This situation is even more strange because the main body isn’t a star but a black hole.
Both quantum computing and machine learning have been touted as the next big computer revolution for a fair while now. However, experts have pointed out that these techniques aren’t generalized tools – they will only be the great leap forward in computer power for very specialized algorithms, and even more rarely will they be able to work on the same problem. One such example of where they might work together is modeling the answer to one of the thorniest problems in physics: how does General Relativity relate to the Standard Model?
Milky Way centre by the MeerKAT array of 65 radio dishes in South Africa. Credit: SAROA
The inner 600 light years of our galaxy is a maelstrom of cosmic radiation, turbulent swirling gas clouds, intense star formation, supernovae, huge bubbles of radio energy, and of course a giant supermassive black hole. This bustling downtown of the Milky Way is a potential treasure trove of discovery but has been difficult to study as the galaxy’s central regions are obscured by dust and glaring radiation. But a new image of this region with unprecedented detail reveals more than we’ve ever seen before. We find some familiar objects like supernovae but also some mysterious structures – gaseous filaments dozens of light years long channeling electrons at near light speed.
Behold, the galaxy’s centre as never seen before:
The new MeerKAT image of the Galactic centre region is shown with the Galactic plane running horizontally across the image. Many new and previously-known radio features are evident, including supernova remnants, compact star-forming regions, and the large population of mysterious radio filaments. Colours indicate bright radio emission, while fainter emission is shown in greyscale. Credit: I. Heywood, SARAO. Image description: SARAOContinue reading “Imaging the Galaxy’s Centre in Unprecedented Detail Reveals More Mysterious Filaments”
While black holes might always be black, they do occasionally emit some intense bursts of light from just outside their event horizon. Previously, what exactly caused these flares had been a mystery to science. That mystery was solved recently by a team of researchers that used a series of supercomputers to model the details of black holes’ magnetic fields in far more detail than any previous effort. The simulations point to the breaking and remaking of super-strong magnetic fields as the source of the super-bright flares.
Artist view of a binary black hole system. Credit: LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet)
In the grand scheme of things, the structure of a black hole is pretty simple. All you need to know is its mass, electric charge, and rotation, and you know what the structure of space and time around the black hole must be. But if you have two black holes orbiting each other, then things get really complicated. Unlike a single black hole, for which there is an exact solution to Einstein’s equations, there is no exact solution for two black holes. It’s similar to the three-body problem in Newtonian gravity. But that doesn’t mean astronomers can’t figure things out, as a couple of recent studies show.
This visible light wide-field view shows the rich star clouds in the constellation of Sagittarius (the Archer) in the direction of the centre of our Milky Way galaxy. The entire image is filled with vast numbers of stars — but far more remain hidden behind clouds of dust and are only revealed in infrared images. This view was created from photographs in red and blue light and forming part of the Digitized Sky Survey 2. The field of view is approximately 3.5 degrees x 3.6 degrees.
It all began with the discovery of Sagittarius A*, a persistent radio source located at the Galactic Center of the Milky Way that turned out to be a supermassive black hole (SMBH). This discovery was accompanied by the realization that SMBHs exist at the heart of most galaxies, which account for their energetic nature and the hypervelocity jets extending from their center. Since then, scientists have been trying to get a better look at Sag A* and its surroundings to learn more about the role SMBHs play in the formation and evolution of our galaxy.
This has been the goal of the GRAVITY collaboration, an international team of astronomers and astrophysicists that have been studying the core of the Milky Way for the past thirty years. Using the ESO’s Very Large Telescope Interferometer (VLTI), this team obtained the deepest and sharpest images to date of the region around Sag A*. These observations led to the most precise measurement yet of the black hole’s mass and revealed a never-before-seen star that orbits close to it.
Another view of NGC 7727 from the Very Large Telescope, taken in 2021. Credit: ESO.
For literally being black in the truest sense of the word, black holes are surprisingly easy to spot. Astronomers have spent decades at this point purposely searching for them and have found thousands already, with potentially 100 billion existing in our part of the universe. We are still finding new types and configurations of black holes consistently. Now, new research led by Dr. Karina Voggel of the Strasbourg Observatory found a pair of black holes that hold the new records of being both the closest supermassive black hole pair to Earth and the closest together pair ever seen.
Patterns in nature often occur in more than one place. Spirals, symmetry, and chaos all impact natural phenomena, from the shape of a shell to the course of a river. So it shouldn’t come as a surprise that one of the most famous and fundamental shapes from biology also appears in astrophysics. Yes, scientists have found a double-helix structure in the magnetic field of M87. And it looks just like a super enlarged DNA strand.
Since the 1970s, scientists have known that within the cores of most massive galaxies in the Universe, there beats the heart of a Supermassive Black Hole (SMBH). The presence of these giant black holes causes these galaxies to be particularly energetic, to the point where their central regions outshine all the stars in their disks combined – aka. Active Galactic Nuclei (AGN). The Milky Way galaxy has its own SMBH, known as Sagittarius A*, which has a mass of over 4 million Suns.
For decades, scientists have studied these objects in the hopes of learning more about their role in galactic formation and evolution. However, current research has shown that SMBHs may not be restricted to massive galaxies. In fact, a team of astronomers from the University of Texas at Austin’s McDonald Observatory recently discovered a massive black hole at the heart of a dwarf galaxy that orbits the Milky Way (Leo I). This finding could redefine our understanding of how black holes and galaxies evolve together.
