Chethma De Mel, Jadetimes Staff
C. J. De Mel is a Jadetimes news reporter covering Entertainment News
All galaxies, including our Milky Way, are slowly dying. Across the universe, the rate of star formation has drastically declined, and galaxies no longer produce new stars at the rate they once did. The universe is still expanding; galaxies continue to move away from one another, with distances growing ever faster. But one important question remains: why such a significant slowdown in star formation? It is not for want of fuel: less than 10% of the gas available to form stars has been converted into stars and the mass of planets is even smaller. Plenty of building materials remain to make new worlds, but for some reason, this gas is not forming new stars and planets as it once did.
The most prominent hypothesis blames super-massive black holes for the demise of the universe. These monsters are normally several millions or billions of times more massive than our Sun in the centers of most galaxies. This enormous mass comes in an incredibly small size compared to the general size of a galaxy. For example, the supermassive black hole at the center of the Milky Way is smaller than the orbit of Venus. And yet, the effect they exert on the galaxy and indeed the universe is immense. It is almost as if a mere atom could stop the growth of a person-for such a force so small to impede the growth of something much larger.
Decades of research have made it plain: enormous quantities of energy are generated around supermassive black holes. These cosmic monsters distort space-time to such an extent that even light cannot escape their gravitational pull. When clouds of gas or stars pass close enough to a black hole, they form an accretion disk, spiraling inward toward the black hole and heating up to extreme temperatures. Because this process emits light so intensely, it can outshine the entire host galaxy. Quasars, the brightest type of AGN, are objects where this light completely eclipses the galaxy itself.
Not only do AGNs emit copious amounts of energy in the form of light, but they also eject material at near light speeds. It is known that these jets may originate just outside the event horizon of the black hole, and can also extend to hundreds of times the size of a galaxy like the Milky Way. The ejected matter prevents surrounding gas from cooling down into new stars, effectively starving the galaxy of what it needs to continue its life cycle.
Recently, astronomers discovered a galaxy—dubbed "Pablo's Galaxy," though more formally known as GS10578—which provides direct evidence into this phenomenon. Using the James Webb Space Telescope, a team of researchers from Spain and the University of Cambridge have detected the expulsion of cold gas from this dying galaxy in the early universe. GS10578 is incredibly large, the size of the Milky Way, yet it formed in less than the blink of an eye when the universe was only 15% of its current age. The super-massive black hole at the center of this galaxy is still active, and the cold gas kicked out has been indirectly observed by blocking light from the stars inside the galaxy.
This discovery lends further credence to the theory that supermassive black holes really do play a crucial role in the slow death of galaxies. AGNs seem to siphon material from their host galaxies, preventing the gas from forming new stars and eventually starving the galaxy to death. As more galaxies like GS10578 are discovered, the evidence of this cosmic process grows stronger.
It might be a similar fate that awaits all galaxies, including our Milky Way. As supermassive black holes continue to exert their pull, one day, all star formation will grind to a halt, and the universe will be without those shimmering stars that have lit it up for billions of years. What remains will be a dark, cold, seemingly hostile universe-a reminder of just how small and transient our existence is within the grand cosmic scheme.
