Scientists have traced mysterious radio signals to a unique cosmic partnership located 1,600 light-years away in the constellation Ursa Major, near the Big Dipper. For the past decade, Earth has been receiving these signals at precise intervals—every 125 minutes, or roughly every two hours.
After years of investigation, researchers have determined that the signals originate from a binary star system, where a white dwarf and a red dwarf star orbit each other so closely that their magnetic fields interact, creating the radio pulses that travel across space to reach us. This system has been named ILTJ1101.
The discovery began when Dr. Iris de Ruiter, now at the University of Sydney, was examining archival data from the Netherlands in 2024.
Using information from the Low Frequency Array (LOFAR), the largest radio telescope operating at low frequencies, she initially found a single pulse that had reached Earth in 2015.
Further analysis revealed six more pulses from the same region of the sky. What made these signals stand out was their duration—lasting anywhere from a few seconds to a minute and their incredibly regular timing.
This slow, steady pattern is rare in astronomy, especially compared to the more commonly observed “fast radio bursts” (FRBs), which last only milliseconds.
At first, only one star was visible—a red dwarf, a small, cool star capable of burning for trillions of years. However, Dr. Kilpatrick, another researcher involved in the study, noticed something unusual.
The spectroscopic data showed that the red dwarf was wobbling back and forth with the same two-hour period as the radio pulses.
This motion revealed the presence of a second star a white dwarf, a dense, dead star that has exhausted its nuclear fuel and is typically too dim to observe directly. As these two stars orbit each other, their magnetic fields collide, generating the radio pulses detected on Earth.
Dr. Kilpatrick explained that these pulses are similar to FRBs but differ in key ways. While FRBs are extremely energetic and last only milliseconds, the pulses from ILTJ1101 are less energetic and can last for several seconds.
This distinction suggests that these signals represent a different class of cosmic event, possibly existing on a continuum with other types of radio emissions or standing as a unique phenomenon altogether.
The discovery of this binary system provides the first direct evidence supporting the hypothesis that long-period radio transients can originate from white dwarf-red dwarf pairs. Dr. Kilpatrick believes this finding will encourage other astronomers to consider binary systems as potential sources of unusual radio signals.
The study not only sheds light on the nature of these mysterious pulses but also opens new avenues for understanding the complex interactions between stars and their magnetic fields in the universe.
As scientists continue to investigate, this extraordinary cosmic partnership may reveal even more secrets about the cosmos and the diverse phenomena it holds.
