Discover Inkathazo: Galaxy With Jets 32 Times Larger Than Our Milky Way

A newly identified galaxy named Inkathazo sends streams of energized matter so far into space that they dwarf the Milky Way by a factor of thirty-two. The find matters because these immense outflows challenge long-standing ideas about how galaxies release energy and how far that influence can reach. Inkathazo was detected using the MeerKAT radio telescope in South Africa, which revealed plasma jets extending roughly 3.3 million light-years from end to end. Researchers call these systems GRGs, short for giant radio galaxies, because their radio-bright jets can extend far beyond the stars. The work was led by Kathleen Charlton, a master’s student at the University of Cape Town. Her research tracks how radio data reveals flows of gas and energy in galaxies, which may explain why some jets keep growing. A telescope built for faint signals MeerKAT links 64 dishes across South Africa, letting the array act as one instrument when signals reach each antenna. That setup lets scientists map the jets at several frequencies, because each dish measures the same signal from a slightly different angle. As surveys deepen, the southern sky should yield more outsized systems that earlier northern searches simply missed. Absolutely massive jets The jets span 3.3 million light-years, about 19 quintillion miles, placing the giant radio galaxy among the largest known single objects. A supermassive black hole, a black hole millions of times the Sun’s mass, can power that reach by launching matter outward. Because the jets tilt in three-dimensional space, the true length could be larger, but the mapped size sets a firm minimum. Naming the Inkathazo galaxy Astronomers chose the name Inkathazo, a word meaning trouble in local South African languages spoken in the region where it was discovered, after the giant radio galaxy resisted easy explanation. “It doesn’t have the same characteristics as many other giant radio galaxies,” said Charlton. One jet bends off-axis, hinting at strong pushes from surrounding cluster gas and leaving fewer simple explanations for how jets evolve. Dense environments usually stunt long radio jets, because surrounding gas pushes back on the flow and strips away energy. The giant radio galaxy sits inside a galaxy cluster, a crowded group of galaxies bound by gravity, where that resistance should be strongest. That location forces scientists to weigh the role of collisions, pressure, and motion, rather than blaming size on age alone. Why the jets glow in radio Radio-bright jets stay hot because they carry plasma, gas with electrons that move freely, far beyond the visible galaxy. As electrons spiral around magnetic fields, they lose energy and emit radio waves, so telescopes can trace invisible structure. That glow fades fastest at higher frequencies, which lets researchers estimate where the jet last received a fresh supply of energy. Dating the Inkathazo galaxy Scientists build a spectral age map, a chart estimating how long electrons have been fading, by comparing radio emission across frequencies in GRGs. Charlton’s team ran that analysis at unusually fine resolution, using MeerKAT data taken in multiple bands. The approach works best when the plasma evolves smoothly, so any sudden brightening signals extra physics that the map alone cannot explain. Signs of fresh energy Age patterns along the giant radio galaxy’s jets looked uneven, with pockets that seemed younger than neighboring regions along the same flow. Researchers suspect particle acceleration, a process that boosts electron energy again, may happen when the jet strikes dense material. Once that re-energizing occurs, the color-based clock resets locally, so simple age estimates can understate how long the jets existed. When jets meet hot gas Cluster centers fill with thin, hot gas that can slow radio jets and stir turbulence around them over large distances. The team points to the intracluster medium, hot gas spread between cluster galaxies, as a likely place for hard collisions. If that interaction drives repeated shocks, models must treat environment as an important cause of jet growth, not a passive setting. COSMOS delivers three giants Repeated scans of the COSMOS field, a well-studied sky region for deep surveys, helped astronomers spot three outsized radio systems. Two of those appeared first in a 2021 paper, after MeerKAT mapped about 1 square degree of sky. Follow-up imaging later exposed the Inkathazo giant radio galaxy, showing that even familiar fields can hold surprises at lower radio frequencies. Better sensitivity, the ability to detect faint emission, turns up giant radio galaxies that older surveys blurred into the noise. The growing catalog will help scientists learn which galaxies launch lasting jets and which conditions let those jets survive. Road to the Square Kilometer Array The Square Kilometre Array, a next-generation global radio observatory, will combine MeerKAT with a much larger network of dishes. An official timeline starts in July 2021 and maps an 8-year build toward early science. As that array grows, researchers can test whether cluster-grown giants are rare exceptions or more typical outcomes. Lessons from the Inkathazo galaxy The hardest part now is explaining how jets keep their energy and direction while crossing dense cluster space. The results suggest that existing models miss some messy behavior in the plasma, especially when jets interact with dense cluster gas. Future work must compare many cluster and non-cluster cases, because one unusual object cannot rewrite the rules by itself. The Inkathazo giant radio galaxy ties together size, bent structure, and local re-energizing, showing how the environment can shape extended radio jets. Larger samples from future surveys will test how common cluster-grown giants are, and they will tighten the physics behind jet lifetimes. The study is published in Monthly Notices of the Royal Astronomical Society. Image credit: K.K.L Charlton (UCT), MeerKAT, HSC, CARTA, IDIA. Licence type: Attribution (CC BY 4.0). —– Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com. —–