Beyond the Milky Way galaxy
There are a number of things in the Universe that could wipe out life as we know it, but — for now, and for Earth — a blast from our galaxy's supermassive black hole isn't one of them. That's not to say that Sagittarius A* doesn't pose a danger. If it wakes up someday and blasts out a strong wind, that definitely could affect Earth. It could well have powered a quasar in the past, and could do so again.
On March 10, 2026, the Fermi telescope gamma-ray burst team reported the detection of a long-duration gamma ray burst that occurred when a star exploded inside a dense, highly magnetized cloud of hydrogen gas. That HII region is a bubble of ionized hydrogen created by winds from a massive young star. Astronomers immediately turned as many telescopes as possible to view the burst and its afterglow, including the NSF's Karl Jansky Very Large Array.
A team of researchers have found a surprisingly simple way to boost the sensitivity of gravitational wave detectors like LIGO. It’s surprisingly simple to, just point an ordinary thermal imaging camera at the mirrors themselves. The technique could improve LIGO's next upgrade by up to 31%, letting it detect neutron star collisions tens of millions of light years farther away, and is already being built into the design of its planned successor, Cosmic Explorer.
Astronomers want to know how universal the initial mass fraction (IMF) of galaxies is. To do they that, they need to discern binary stars in other galaxies, a difficult task. Researchers used the JWST to study the Small Magellanic Cloud and determine how many binary stars are there, since they can confuse measurements of the IMF.
In recent years, the idea that galaxy mergers are responsible for quenching galaxies has grown in importance. This paradigm says that galaxies merge, their black holes form a powerful quasar, and that quasar stifles star formation. But new results from the IllustrisTNG simulations shows that this paradigm may not be accurate.
Little Red Dots are one of the mysteries uncovered by the JWST. Astronomers have been trying to figure out what they are, and have come up with multiple possibilities. New research says they could be ancient Globular Clusters with supermassive stars in their centers.
Spiral galaxies, including grand spirals like the Whirlpool galaxy, are plentiful. But it's still a mystery how their spiral arms form and persist for hundreds of millions of years, and why some galaxies have one, two, or three or more arms. New research based on Euclid data finds links between galaxy mass, star formation rate, and number of arms, and hints at their formation.
Astronomers thought that early galaxies were messy, clumpy, and turbulent from mergers. That means their gas was all stirred up. So what could explain the rapid star formation during the Cosmic Noon? New research shows that galaxies had well-ordered morphologies earlier than thought, and that their spiral arms and bars allowed gas to flow freely, forming more stars.
Euclid is only 1.5 years into its Euclid Wide Survey and has found 31 new quasars from the Universe's first 800 million years. Though the Survey isn't specifically aimed at finding ancient quasars, it's proving to be remarkably effective at it. This large sample of quasars will help with the study of ancient galaxies and supermassive black holes.
Mergers are a part of a galaxy's life in this Universe. Though clear signs of these mergers fade over hundreds of millions of years, evidence is still present, yet obscured, in the galaxies that experience them. The powerful JWST has made it possible to find this evidence, and it did so recently for Centaurus A.
Astronomers have discovered an extremely low-mass and dim dwarf galaxy around Andromeda. Called And 35, it's an Ultra-Faint Dwarf Galaxy (UFDG) and so far, the researchers have detected only 46 of its stars. Lambda-CDM predicts that there should be many UFDGs around galaxies like Andromeda and the Milky Way, so finding more of them is important.
Scale in the universe is hard to understand from a purely human perspective. Many times the math just doesn’t sit well with our brains that evolved to capture and process data about the world around us rather than groking the complexities of stellar dynamics and galaxy mergers. But every once in a while astronomers find something that, if we can wrap our heads around the numbers, gives a sense of just how big the universe is. That is precisely what a new paper, available in preprint on arXiv from a group of astronomers led by Z.L. Wen of the Chinese Academy of Sciences, hopes to do when it describes a merger of not one, not two, but six supermassive galaxies and the active dynamics they’re subject to.
Even the universe’s emptiest regions, the vast voids that make up most of the volume of space, are not entirely empty. A new study using the CAVITY survey hunts for galaxy groups hiding within these voids, applying a friends of friends technique to chart how nearby galaxies cluster together despite the surrounding emptiness. The results paint a striking picture that most void galaxies actually live entirely solitary lives, yet where groups do form, they are small, loose and curiously indifferent to just how empty their void actually is. It raises a deceptively simple question that turns out to be anything but: in the universe’s quietest neighbourhoods, what makes some galaxies choose company while most remain alone?
On September 22, 2021, the IceCube Neutrino Detector in Antarctica caught a blast of neutrinos as it passed through the solar system. These neutrinos were remarkably high-energy and came from a galaxy 11 billion light-years away. That's a period of the Universe's history known as "Cosmic Noon". It's when star formation in galaxies was at its most active and that provided an interesting clue to their origin. The source of the neutrinos was nicknamed "Shadow Blaster" because the event that created the neutrinos was hidden by a dense cloud of dust, which made it invisible to optical observations.
Astronomers have discovered a galaxy so unlike anything in the textbooks that the researcher who found it, after 25 years studying these objects, says he has never seen its equal. Named RAD-BAARG, it is falling supersonically into a distant cluster of galaxies and ploughing up a glowing arc of radio plasma nearly 1.8 million light years across, shaped uncannily like a bow and arrow. It offers astronomers their clearest view yet of a bow shock, a structure long predicted but almost never glimpsed. And in a final twist, the first person to spot it was not a professional at all, but a student combing through telescope data from a remote hillside in the Himalayas.
For its first billion years the universe was lost in fog, a thick haze of hydrogen that swallowed light whole. Something burned it away, and astronomers have long wondered what. Now Hubble has caught a tiny, furious galaxy in the very act of clearing the murk, glimpsed as it was just 1.4 billion years after the big bang. It may be the smoking gun for how the universe first became clear.
The JWST looked back in time and saw 6 galaxies merging into one. At the heart of the assembly, a supermassive black hole is lurking. It all happened when the Universe was only about 1.5 billion years old, and the red-shifted light is just reaching us now.
The JWST found a galaxy cluster from 10 billion years ago that's far more developed than it should be, according to cosmological models. The cluster is also the most distant strong gravitational lens that we know of. Detailed observations across the spectrum show that the cluster is still undergoing mergers.
A small lump of rock pulled up from the Pacific Ocean seafloor in 1976 is giving scientists new clues about an ancient cosmic event. More than a hundred million years ago, two neutron stars collided. The resulting energetic kilonova sent a rain of long-lived elements, such as isotopes of plutonium, through space. Eventually, this stellar "debris" settled onto Earth. Some sank to the bottom of the ocean and got incorporated into a chunk of ferromanganese rock. Hidden inside were a few hundred atoms of plutonium radioisotopes. They provide the strongest clues about what created them in the merger and how long ago it happened.
Every galaxy you've ever seen in a photograph is hiding something. Beyond the glowing disc of stars and gas that the camera captures lies a vast, ghostly outer region called a halo, too faint to see easily but packed with clues about how that galaxy came to be. ESA has just formally committed to a mission designed to reveal those hidden haloes in unprecedented detail, and in doing so, finally answer one of the most fundamental questions in astronomy: how did galaxies like our own Milky Way form?
Universe Today