Astronomers using NASA’s Chandra X-ray Observatory have made a remarkable discovery in the galaxy cluster Zwicky 8338, identifying two streams of superheated gas that intersect. This interaction suggests that crossing streams could lead to the formation of new structures.
Among their findings is an enormous, comet-like tail of hot gas extending over 1.6 million light-years behind a galaxy, created as the galaxy loses some of its gas while moving through a hot medium. Interestingly, this is the second pair of gas tails identified in the cluster; a previous observation revealed a shorter pair from another nearby galaxy. The newer, longer streams became visible thanks to a deeper Chandra observation that highlighted fainter X-ray emissions.
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| In the intricate landscape of the Zwicky 8338 galaxy cluster, astronomers have uncovered fascinating structures in the form of gas tails trailing behind rapidly moving galaxies. These tails, shaped by interactions within the cluster, offer insights into the dynamic processes at play in one of the universe’s chaotic environments. The composite images showcase both X-ray emissions from NASA’s Chandra X-ray Observatory and optical data from the Dark Energy Survey, illustrating the remarkable phenomena occurring in this distant region of space. |
Astronomers have now observed evidence of intersecting streams of gas trailing behind rapidly moving galaxies in the chaotic landscape of the Zwicky 8338 (Z8338) galaxy cluster. This region, formed by the collision of two galaxy clusters, is characterized by galaxies, superheated gas, and shock waves, reminiscent of sonic booms from supersonic jets.
A new composite image captures this phenomenon, with X-rays from the Chandra X-ray Observatory depicted in purple, revealing multimillion-degree gas that exceeds the mass of the galaxies. The optical data from the Dark Energy Survey complements this view, showcasing the individual galaxies scattered throughout the cluster.
The original gas tail, measuring about 800,000 light-years, appears vertical in the image and is thought to be stripped from a large galaxy as it traverses the cluster. The head of this tail consists of cooler gas, located approximately 100,000 light-years from its galaxy of origin. Notably, this tail is divided into two sections.
Researchers suggest that the detachment of this tail may have been triggered by the passage of the longer tail, resulting from the crossing streams. Their findings indicate that clouds of cooler gas, like those in the tail’s head, can persist for at least 30 million years post-detachment, potentially allowing for the formation of new stars and planets.
Located about 670 million light-years from Earth, the Z8338 cluster’s complex structure was detailed in a paper published on August 8, 2023, in the Monthly Notices of the Royal Astronomical Society. NASA’s Marshall Space Flight Center manages the Chandra program, with scientific operations overseen by the Smithsonian Astrophysical Observatory’s Chandra X-ray Center.
Image Description.
This release features a composite image showcasing two pairs of hot gas tails within the Zwicky 8338 galaxy cluster. The image is available in both labeled and unlabeled formats, with color-coded ovals highlighting the gas tails.
In both versions, mottled purple gas permeates the region, accented by distant flecks of red and white. Scattered throughout are glowing golden dots representing individual galaxies within the cluster.
To the right of center, a golden galaxy is accompanied by a mottled V-shaped cloud of purple gas above it. Yellow labels identify the two arms of the V as the tails trailing from this rapidly moving galaxy.
On the left side of the image, another golden galaxy is surrounded by purple gas. Behind it, two larger mottled purple clouds open toward the right, forming a sideways widening V. Labeled in white, these newly discovered gas tails surpass the previously identified ones, stretching over 1.6 million light-years and overlapping with the galaxy on the right.