ASKAP J1832-0911

ASKAP J1832-0911 is a newly discovered and highly enigmatic cosmic object located about 15,000 light-years from Earth in the Milky Way. It has garnered significant attention from astronomers due to its unprecedented behaviour as the object emits simultaneous pulses of both radio waves and X-rays — a phenomenon never observed in this combination or periodicity. The initial detection was made using the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope, followed by a fortuitous observation with NASA’s Chandra X-ray Observatory, which captured the X-ray pulses during a period of intense radio emission. Follow-up observations revealed that the intensity of both radio and X-ray emissions can vary over months, with the object sometimes dropping off dramatically in both wavelengths. 
 
ASKAP J1832-0911 belongs to a rare class known as long-period transients (LPTs). LPTs are astrophysical objects that emit intermittent, regular bursts of radio waves spaced out by minutes or hours, first identified in 2022. Only about ten such objects have been catalogued so far, and none have shown the same properties as ASKAP J1832-0911. It emits strong, periodic pulses in both radio and X-ray wavelengths, lasting two minutes every 44.2 minutes. This cycle is thousands of times longer than the rapid pulses seen from typical pulsars, which repeat multiple times per second. This is also the first time an LPT has been observed emitting both radio and X-ray pulses in sync, suggesting a highly energetic and unusual underlying mechanism. It reaches radio luminosities up to 10,000 times greater than typical pulsars, with peak radio fluxes around 20 Janskys. Its radio pulses are also highly polarized (92% total polarization), indicating extremely ordered magnetic fields — far exceeding the polarization seen in most other transient sources. The combination of long-period, high-brightness, synchronized multi-wavelength emission, and extreme variability does not fit any established category of compact objects, such as pulsars, magnetars, or accreting binaries. Its properties defy current models of stellar remnants and challenge our understanding of how such objects can remain so active with such slow rotation.
 
Astronomers are still debating the true nature of ASKAP J1832-0911. Several hypotheses have been proposed:

It could be a highly magnetic neutron star (magnetar), which are known to emit both radio and X-ray pulses. However, some aspects — such as the brightness and variability of the radio emission are challenging to reconcile with known magnetar behaviour, especially for an older magnetar (over half a million years old).
Another theory is that ASKAP J1832-0911 is part of a binary system, possibly involving a highly magnetized white dwarf. Yet, this also fails to fully explain the observed phenomena.

​The object’s unique combination of properties may point to a new type of physics or previously unknown models of stellar evolution, as current theories do not fully account for its behavior.
                  
The discovery of ASKAP J1832-0911 opens a new window into the study of long-period transients and the extreme physics governing such objects. Its dual emission in radio and X-ray bands provides a crucial clue that could help unravel the mechanisms behind LPTs and similar cosmic phenomena. Researchers plan to continue monitoring ASKAP J1832-0911 and search for other LPTs with similar properties. Further X-ray and radio observations may help determine the object’s temperature, size, and underlying physical processes, potentially reshaping our understanding of stellar remnants and high-energy astrophysics.
 
References
Lea, R. (2025, May 28). Astronomers discover mystery cosmic body bursting with X-rays: 'This object is unlike anything we have seen before.' Space.com.
 
Turner, B. (2025, May 28). 'Unlike anything we have seen before': Astronomers discover mysterious object firing strange signals at Earth every 44 minutes. LiveScience. 
(2025). Eccentric 'Star' Defies Easy Explanation, NASA's Chandra Finds. Chandra X-Ray Observatory. https://chandra.si.edu/photo/2025/lprt/
 
(2025, May 28). Mysterious Star Pulses Every 44 Minutes In Space First. NASA/JPL. Science Blog. https://scienceblog.com/mysterious-star-pulses-every-44-minutes-in-space-first/