Latest news with #Balashev
Business Mayor
25-05-2025
- Science
- Business Mayor
Space photo of the week: Violent galaxies seen 'jousting' near the dawn of time
Quick facts What it is: Two galaxies colliding in the early universe Where it is: 11 billion light-years away, in the constellation Cetus When it was shared: May 21, 2025 If you get up before sunrise any day this month, you'll see bright Venus rising in the east. Just below it, in the constellation Cetus (The Whale), something spectacularly violent is happening in the distant background: a 'cosmic joust' between two giant galaxies. There, 11 billion light-years from Earth and close to the beginning of the universe itself, two galaxies are moving toward each other at speeds of 310 miles per second (500 kilometers per second), destined to collide before retreating and colliding again and again. Captured by the European Southern Observatory's Very Large Telescope and Atacama Large Millimeter/submillimeter Array in Chile and published this week in Nature, the image is unique because one of the galaxies is a quasar, in which a supermassive black hole consumes so much gas and dust that it produces a glowing disk at the center of a galaxy. According to the European Space Agency , quasars are among the most luminous objects in the known universe, typically emitting thousands of times more light than the entire Milky Way. This quasar, J012555.11−012925.00, is shown on the right of the image. As the galaxy on the right collides with the galaxy on the left, it pierces its clouds of gas and dust with intense radiation — hence the comparison to the medieval sport of jousting — inhibiting the galaxy's ability to form new stars. The collision between these two galaxies leaves the one on the left in a much worse state. It's the first time astronomers have witnessed such a collision. 'Here we see for the first time the effect of a quasar's radiation directly on the internal structure of the gas in an otherwise regular galaxy,' Sergey Balashev , co-lead of the study and a researcher at the Ioffe Institute in St. Petersburg, Russia, said in a statement . The observations indicate that the spear of radiation from the quasar leaves intact only the densest regions of gas and dust, which are likely too small to form stars. Related: Cotton candy clouds shine in one of Hubble's most beautiful images ever Get the world's most fascinating discoveries delivered straight to your inbox. Not surprisingly, the depletion of the companion galaxy leaves the quasar stronger, which provides new fuel to the supermassive black hole powering the quasar. 'These mergers are thought to bring huge amounts of gas to supermassive black holes residing in galaxy centers,' Balashev said. In addition to this spectacular image, the European Southern Observatory published videos on YouTube that explain the science , zoom in on the galactic collision , and give an artist's impression of the violent event. For more sublime space images, check out our Space Photo of the Week archives .
Ammon
22-05-2025
- Science
- Ammon
Two galaxies seen in a 'joust' preceding a cosmic mega-merger
Ammon News - Astronomers have observed two distant galaxies - both possessing roughly as many stars as our Milky Way - careening toward each other before their inevitable merger at a time when the universe was about a fifth its current age, a scene resembling two knights charging in a joust. The galaxies, observed using two Chile-based telescopes, were seen as they existed about 11.4 billion years ago, approximately 2.4 billion years after the Big Bang event that initiated the universe. At the heart of one of the galaxies resides a quasar, a highly luminous object powered by gas and other material falling into a supermassive black hole. The intense radiation across the electromagnetic spectrum unleashed by the quasar is seen disrupting clouds of gas and dust, known as molecular clouds, in the other galaxy. It is molecular clouds that give rise to stars. But the effects of the quasar's radiation turned the clouds in the affected region into "only tiny dense cloudlets that are too small to form stars," said astrophysicist Sergei Balashev of the Ioffe Institute in Saint Petersburg, Russia, co-lead author of the study published on Wednesday in the journal Nature, opens new tab. This is the first time such a phenomenon has been observed, Balashev said. Stars form by the slow contraction under gravity of these clouds, with small centers taking shape that heat up and become new stars. But the galaxy affected by the quasar's radiation was left with fewer regions that could serve as such stellar nurseries, undermining its star formation rate. The interaction between the two galaxies reminded the researchers of a medieval joust. "Much like jousting knights charging toward one another, these galaxies are rapidly approaching. One of them - the quasar host - emits a powerful beam of radiation that pierces the companion galaxy, like a lance. This radiation 'wounds' its 'opponent' as it disrupts the gas," said astronomer and co-lead author Pasquier Noterdaeme of the Paris Institute of Astrophysics in France. You might think that a mummified corpse would have a fairly unpleasant stink. Supermassive black holes are found at the heart of many galaxies, including the Milky Way. The researchers estimated the mass of the one that serves as the engine of the quasar studied in this research at about 200 million times that of our sun. The intense gravitational strength of the supermassive black hole pulls gas and other material toward it. As this stuff spirals inward at high speed, it heats up due to friction, forming a disk that emits extremely powerful radiation in two opposite directions, called biconical beams. The ultraviolet light from one of these beams is what played havoc with the gas in the companion galaxy. This supermassive black hole is much more massive than the one at the center of the Milky Way - called Sagittarius A*, or Sgr A* - which possesses roughly 4 million times the mass of the sun and is located about 26,000 light-years from Earth. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The researchers used the Atacama Large Millimeter/submillimeter Array, or ALMA, to characterize the two galaxies and used the European Southern Observatory's Very Large Telescope, or VLT, to probe the quasar as well as the gas in the companion galaxy. The configuration of the galaxies as viewed from the perspective of Earth enabled the researchers to observe the radiation from the quasar passing directly through the companion galaxy. Most galactic mergers that have been observed by astronomers occurred later in the history of the universe. "Galaxies are typically found in groups, and gravitational interactions naturally lead to mergers over cosmic time," Noterdaeme said. "In line with current understanding, these two galaxies will eventually coalesce into a single larger galaxy. The quasar will fade as it exhausts the available fuel." Reuters
Korea Herald
22-05-2025
- Science
- Korea Herald
Two Galaxies in 'joust' before mega-merger
WASHINGTON (Reuters) — Astronomers have observed two distant galaxies — both possessing roughly as many stars as our Milky Way — careening toward each other before their inevitable merger at a time when the universe was about a fifth its current age, a scene resembling two knights charging in a joust. The galaxies, observed using two Chile-based telescopes, were seen as they existed about 11.4 billion years ago, approximately 2.4 billion years after the Big Bang event that initiated the universe. At the heart of one of the galaxies resides a quasar, a highly luminous object powered by gas and other material falling into a supermassive black hole. The intense radiation across the electromagnetic spectrum unleashed by the quasar is seen disrupting clouds of gas and dust, known as molecular clouds, in the other galaxy. It is molecular clouds that give rise to stars. But the effects of the quasar's radiation turned the clouds in the affected region into "only tiny dense cloudlets that are too small to form stars," said astrophysicist Sergei Balashev of the Ioffe Institute in Saint Petersburg, Russia, co-lead author of the study published on Wednesday in the journal Nature. This is the first time such a phenomenon has been observed, Balashev said. Stars form by the slow contraction under gravity of these clouds, with small centers taking shape that heat up and become new stars. But the galaxy affected by the quasar's radiation was left with fewer regions that could serve as such stellar nurseries, undermining its star formation rate. The interaction between the two galaxies reminded the researchers of a medieval joust. "Much like jousting knights charging toward one another, these galaxies are rapidly approaching. One of them — the quasar host — emits a powerful beam of radiation that pierces the companion galaxy, like a lance. This radiation 'wounds' its 'opponent' as it disrupts the gas," said astronomer and co-lead author Pasquier Noterdaeme of the Paris Institute of Astrophysics in France. Supermassive black holes are found at the heart of many galaxies, including the Milky Way. The researchers estimated the mass of the one that serves as the engine of the quasar studied in this research at about 200 million times that of our sun. The intense gravitational strength of the supermassive black hole pulls gas and other material toward it. As this stuff spirals inward at high speed, it heats up due to friction, forming a disk that emits extremely powerful radiation in two opposite directions, called biconical beams. The ultraviolet light from one of these beams is what played havoc with the gas in the companion galaxy. This supermassive black hole is much more massive than the one at the center of the Milky Way — called Sagittarius A*, or Sgr A* — which possesses roughly 4 million times the mass of the sun and is located about 26,000 light-years from Earth. A light-year is the distance light travels in a year, 9.5 trillion kilometers. The researchers used the Atacama Large Millimeter/submillimeter Array, or ALMA, to characterize the two galaxies and used the European Southern Observatory's Very Large Telescope, or VLT, to probe the quasar as well as the gas in the companion galaxy. The configuration of the galaxies as viewed from the perspective of Earth enabled the researchers to observe the radiation from the quasar passing directly through the companion galaxy. Most galactic mergers that have been observed by astronomers occurred later in the history of the universe. "Galaxies are typically found in groups, and gravitational interactions naturally lead to mergers over cosmic time," Noterdaeme said. "In line with current understanding, these two galaxies will eventually coalesce into a single larger galaxy. The quasar will fade as it exhausts the available fuel."
