Buzz
Astronomers have detected an unprecedented stellar eclipse in a distant binary star system. Every 69 years, the newly discovered system, TYC 2505-672-1, experiences a period of darkness lasting nearly years. A forthcoming study in the *Astronomical Journal* reveals that this event holds the record for both the longest eclipse duration and the longest interval between eclipses ever documented.
The researchers note that TYC 2505-672-1 surpassed the previous record set by Epsilon Aurigae, a star that undergoes an eclipse every 27 years, lasting up to 730 days. "Epsilon Aurigae is significantly closer, about 2200 light-years from Earth, and much brighter, which has enabled astronomers to examine it in great detail," explains Joey Rodriguez, the lead author of the study.
In contrast, TYC 2505-672-1 lies nearly 10,000 light-years from Earth, making it more challenging to observe. Scientists believe the system’s two stars are red giants—one being the primary star, and the other a "stripped" companion star with a smaller core, surrounded by an enormous disk of material that could cause the eclipse. This companion star is approximately 2000 degrees Celsius hotter than the Sun. To explain the long gap between eclipses, researchers hypothesize that the stars orbit each other at a distance of about 20 astronomical units (roughly the distance from the Sun to Uranus).
Astronomer Keivan Stassun highlights that the star system offers a rare opportunity for researchers. Many astronomical events unfold so far away and over such extended periods that they are hard to observe within a single human lifetime. However, with TYC 2505-672-1, astronomers have had access to a century's worth of data collected by Harvard University researchers from 1890 to 1989.
"One of the major challenges in astronomy is that many key phenomena occur on timescales far beyond human lifespans, yet astronomers are typically confined to much shorter periods," explains Stassun. "Here, we have a rare chance to study a phenomenon that spans several decades, offering a glimpse into the types of environments around stars that may serve as the building blocks for planets at the end of a star system's lifecycle."
