Astronomers recently detected a remarkable event—a powerful eruption from a black hole within the SDSS J1531+3414 system, aptly abbreviated as SDSS J1531. This colossal explosion, dating back billions of years, holds potential clues about the origin of a captivating arrangement of star clusters surrounding two immense galaxies, forming a bead-like pattern. SDSS J1531 is a colossal galaxy cluster housing numerous galaxies, substantial reservoirs of hot gas, and dark matter. Positioned roughly 3.8 billion light-years away, this cluster features a collision between two of its largest galaxies at its core, adding a dynamic dimension to the cosmic spectacle.
Astronomers employed multiple telescopes, including NASA’s Chandra X-ray Observatory and the Low Frequency Array (LOFAR), a radio telescope, to scrutinize SDSS J1531. This composite image presents the X-ray view from Chandra (blue and purple) merged with radio data from LOFAR (dark pink) and an optical image from the Hubble Space Telescope (appearing as yellow and white). The inset provides a close-up of SDSS J1531’s center in optical light, revealing two prominent galaxies and 19 large star clusters, termed superclusters, arranged in an ‘S’ formation reminiscent of beads on a string.
The diverse data sources reveal clues of an ancient, colossal eruption within SDSS J1531, believed by a team of researchers to be linked to the formation of the 19 star clusters. They propose that an exceptionally potent jet emitted from the supermassive black hole at the center of one of the large galaxies expelled the surrounding hot gas, forming a massive cavity. Bright X-ray emission “wings” observed with Chandra indicate dense gas near the center, outlining the edges of the cavity. LOFAR captures radio waves emanating from the remnants of the jet’s energetic particles filling the expansive cavity, as illustrated in a labeled version of the image.
Multiwavelength Image of SDSS J1531.
Astronomers, utilizing the Atacama Large Millimeter and submillimeter Array (ALMA) and the Gemini North Telescope, identified both cold and warm gas near the cavity’s entrance. A supplemental graphic illustrates the optical image with added cold gas in green (left) and warm gas in red (right). The researchers posit that a portion of the hot gas expelled from the black hole underwent cooling processes, resulting in the observed cold and warm gases.
They suggest that tidal effects from the merging galaxies compressed the gas along curved trajectories, leading to the formation of the star clusters arranged in the distinctive “beads on a string” pattern.
Cold and warm gas.
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Astronomers have detected both cold and warm gas in close proximity to the opening of the cavity within SDSS J1531. |
The galaxy cluster SDSS J1531+3414, at redshift z=0.335, unfolds as a captivating celestial laboratory for exploring the intricate dynamics of mergers, AGN feedback, and star formation. Recent Chandra X-ray imaging exposes the rapid cooling of intracluster gas (T∼106 K), forming two distinctive “wings” with a concave density discontinuity at the cool core’s edge.
LOFAR 144 MHz observations reveal diffuse radio emission precisely aligned with these “wings,” implying their role as the entrance to a colossal X-ray supercavity. The steep radio emission suggests an ancient remnant of an energetically intense AGN outburst exceeding 4pV>1061 erg. GMOS detects warm (T∼104 K) ionized gas north of the supercavity, enveloping stellar superclusters but redshifted up to +800 km s−1 relative to the southern central galaxy.
ALMA identifies a redshifted ∼1010 M⊙ reservoir of cold (T∼102 K) molecular gas, offset by ∼1−3 kpc from the young stars. The proposed origin of multiphase gas involves low-entropy gas entrained by the X-ray supercavity, attributing the offset to turbulent intracluster gas motions, and suggesting tidal interactions as catalysts for the observed “beads on a string” star formation morphology.
The findings, detailed in a paper led by Osase Omoruyi from the Center for Astrophysics | Harvard & Smithsonian (CfA), have been recently published in The Astrophysical Journal and are accessible online here. The collaborative team of authors includes researchers from institutions worldwide, such as Grant Tremblay (CfA), Francoise Combes (Paris Observatory, France), Timothy Davis (Cardiff University, UK), and others.
Visual Description of Galaxy Cluster SDSS J1531+3414.
The image captures the galaxy cluster SDSS J1531+3414 in X-ray, optical, and radio wavelengths, resembling a mesmerizing display of lights viewed through a wet glass window. Blurry orange dots, representing entire galaxies, scatter across a black background. Two bright, white dots at the center depict the central galaxies, while electric blue star clusters form a string-like pattern, intertwining around the left galaxy, through the space between the pair, and lightly coiling beneath them.
Surrounding the galaxies, a blend of blue X-ray and dark pink radio clouds extends for thousands of light-years. The dark pink cloud below signifies the remnants of a potent jet expelled by a supermassive black hole, resembling an upside-down spinning top. Another dark pink cloud in the upper right corner may denote the relic of a counter-jet from the same black hole outburst.
