“We discovered what we think is a black hole merging with a massive companion star, shredding it into a disk that feeds the black hole. It’s a rare and awe-inspiring phenomenon,” said Daniel Perley, describing an outburst nicknamed Whippet (AT2024wpp).
For engineers and astronomers alike, the arresting part is not the drama of destruction but the signal quality: an otherwise hidden system briefly made itself measurable across the spectrum. At its peak, the event’s light implied an energy release of 400 billion times the Sun’s output, pushing beyond the familiar ceiling set by ordinary stellar explosions and forcing a re-check of how “fast transients” are categorized.
Whippet sits in the family of tidal disruption events episodes where gravity overwhelms a star and turns it into a stream of debris. What separates this one is scale and speed. Data indicate an extreme version of the process: a black hole, inferred to be up to ~100 solar masses, dismantling a massive companion in days rather than slowly stripping it over long periods. That conclusion matters because black holes in this mass range are difficult to study directly; they are rarely “lit” by surrounding gas in a way that telescopes can easily pinpoint.
The event also fits the profile of a luminous fast blue optical transient (LFBOT), a class once treated as oddball supernovae. Observations of Whippet strengthen a different picture: LFBOTs require a compact, continuously powered engine accretion rather than a one-time blast. One analysis found Whippet radiated ~100 times the energy a normal supernova emits, concentrated into the first weeks. The team used Zwicky Transient Facility detections to trigger rapid follow-up, then stitched together ultraviolet, optical, infrared, X-ray, and radio measurements to show the outburst could not be explained by a standard collapse-and-explosion scenario.
That multi-instrument choreography is the real modern marvel. Whippet was flagged quickly, then examined with space-based and ground-based assets NASA’s Swift among them before the most information-rich phases faded. Later spectra added further texture: extremely faint hydrogen and helium features were detected after the early, nearly featureless blue phase, consistent with a changing line of sight into an evolving, asymmetric environment around the accretion flow. Separate near-infrared observations also showed a surplus of infrared emission, a feature seen only rarely in this class and increasingly treated as a hallmark that models still struggle to reproduce.
Beyond the fireworks, the practical consequence is a new locating method. Events like Whippet provide a way to map where black holes reside inside their host galaxies and to constrain how quickly matter can be processed into radiation when a disk forms abruptly. With surveys designed to catch more fast transients, Whippet effectively serves as a calibration point an existence proof that a “blue flash” can be a black hole’s feeding episode, not a star’s final detonation.
