Radio Telescopes Uncover Hidden Gas Surrounding an Astonishing Cosmic Explosion
Press Releases (https://www.almaobservatory.org/en/category/press-releases/)
January 13, 2026 / Estimated Reading Time: 4 minutes
Scientific Paper (https://www.astro.ljmu.ac.uk/~aridperl/draft/AT2024wpp.pdf)
In a groundbreaking discovery, astronomers utilizing the Atacama Large Millimeter/submillimeter Array (ALMA) alongside various radio observatories have identified dense gas enveloping one of the most powerful cosmic explosions recorded to date. This remarkable finding suggests that material previously thought to be nonexistent was, in fact, present but hidden from optical telescopes due to intense radiation, only becoming visible at radio and millimeter wavelengths.
The explosive event, designated AT2024wpp and informally referred to as "the Whippet," belongs to a rare category known as Luminous Fast Blue Optical Transients (LFBOTs). These spectacular occurrences brighten and diminish in brightness swiftly while emitting energy levels that far surpass those of typical stellar explosions.
"While we had our suspicions about its nature, the results were still astonishing," shared Daniel A. Perley, the principal investigator of this study. "This explosion exhibited energy levels many times greater than any similar event and surpassed all known explosions caused by the collapse of stars."
AT2024wpp was first detected in September 2024 by the Zwicky Transient Facility. Subsequent observations uncovered a very hot, blue source radiating strong X-rays. However, initial optical data indicated minimal evidence of nearby material.
Utilizing ALMA and the National Science Foundation’s Very Large Array, researchers conducted radio and millimeter observations that revealed a rapidly expanding shock wave moving at approximately one-fifth the speed of light into a dense gas region surrounding the explosion. The absence of visibility at optical wavelengths was due to intense X-ray radiation stripping electrons from atoms, which suppressed traditional spectral signatures while leaving the radio emissions intact.
These observations support a theory suggesting that the explosion was fueled by a colossal black hole drawing in material from a massive companion star. Before its ultimate disintegration, the star expelled significant amounts of gas, forming a dense shell around the system. When the star was torn apart, the debris produced the observed emissions.
Further spectroscopic observations confirmed the presence of high-velocity hydrogen and helium, reinforcing the evidence for dense gas in the vicinity of the explosion.
"These events not only aid us in identifying black holes, but they also offer new insights into their locations, formation, growth processes, and the underlying physics involved," added Perley.
These findings underscore the vital role that radio and millimeter-wave observations play in uncovering extreme cosmic environments that remain obscure at optical wavelengths.
Additional Information
This research was published under the title "AT2024wpp: An Extremely Luminous Fast Ultraviolet Transient Powered by Accretion onto a Black Hole" by Daniel A. Perley and colleagues, and was presented at the American Astronomical Society’s annual meeting in January.
This article is derived from a press release issued by the National Radio Astronomy Observatory in the United States, which partners with ALMA on behalf of North America, along with the original press release from the Astrophysics Research Institute at Liverpool John Moores University.
The Atacama Large Millimeter/submillimeter Array (ALMA) is a major international astronomical facility and is a collaboration between the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF), and Japan's National Institutes of Natural Sciences (NINS), in partnership with the Republic of Chile. ALMA receives funding from ESO on behalf of its Member States, from NSF in collaboration with the National Research Council of Canada (NRC) and Taiwan’s National Science and Technology Council (NSTC), and from NINS alongside Taiwan’s Academia Sinica (AS) and the Korea Astronomy and Space Science Institute (KASI).
The construction and operations of ALMA are overseen by ESO on behalf of its Member States, by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America, and by the National Astronomical Observatory of Japan (NAOJ) representing East Asia. The Joint ALMA Observatory (JAO) is responsible for the unified leadership and management of ALMA's construction, commissioning, and operational phases.
