In Star Trek, a subspace compression anomaly is a rare subspace astronomical phenomenon, that miniaturizes objects that enter its accretion disk. These anomalies emit high levels of gamma radiation.

In 2374, Starfleet ordered the USS Defiant to investigate one such anomaly, in the hopes of collecting data that could lead to the development of transwarp corridors. The runabout USS Rubicon was lowered into the anomaly with a tractor beam, where it shrank to a fraction of its normal size. The mission was interrupted by a Jem'Hadar ambush. Contrary to predictions, the Rubicon did not return to normal size when it left the anomaly. After helping to defeat the Jem'Hadar in its miniaturized state, the runabout and its crew were restored to normal size by re-entering the anomaly along its previous course. (DS9: "One Little Ship").

There are certainly no known actual astrophysical phenomena that can miniaturize objects intact. However, many astrophysical phenomena do emit gamma radiation. Gamma-ray bursts (GRBs) are the most luminous electromagnetic events occurring in the universe since the Big Bang. They are flashes of gamma rays emanating from seemingly random places in deep space at random times. The duration of a gamma-ray burst is typically a few seconds, but can range from a few milliseconds to several minutes, and the initial burst is usually followed by a longer-lived "afterglow" emitting at longer wavelengths (X-ray, ultraviolet, optical, infrared, and radio). Gamma-ray bursts are detected by orbiting satellites about two to three times per week.

Most observed GRBs appear to be collimated emissions caused by the collapse of the core of a rapidly rotating, high-mass star into a black hole. A subclass of GRBs (the "short" bursts) appear to originate from a different process, the leading theory being the collision of neutron stars orbiting in a binary system. All observed GRBs have originated from outside our own galaxy; though a related class of phenomena, SGR flares, are associated with galactic magnetars. The sources of most GRBs have been billions of light years away.