In a groundbreaking discovery, scientists using NASA’s Transiting Exoplanet Survey Satellite (TESS) have uncovered a record-breaking triple-star system, so tightly bound that it could comfortably fit between our Sun and the planet Mercury. This remarkable system, designated TIC 290061484, is located just under 5,000 light-years away in the constellation Cygnus, the swan.
The system’s unique configuration features twin stars that race around each other every 1.8 Earth days, while a third star orbits this pair once every 25 Earth days. This incredibly close-knit dance of stars sets a new record for the tightest three-star system orbit, surpassing the previous record holder, Lamba Tauri, which was discovered in 1956.
This discovery, fueled by a collaboration between citizen scientists and professional astronomers, offers a unique opportunity to study the evolution of star systems. “Thanks to the compact, edge-on configuration of the system, we can measure the orbits, masses, sizes and temperatures of its stars,” explained Veselin Kostov from NASA’s Goddard Space Flight Center and a member of the SETI Institute. “We can study how the system formed and predict how it may evolve.”
The team believes that the stability of this triple-star system stems from the stars orbiting each other in nearly the same plane. If their orbits were tilted in different directions, their gravitational forces would disrupt their orbits, making the system unstable.
However, this remarkable stability is not permanent. In a few million years, the twin stars at the heart of the system will expand outward and ultimately merge, triggering a massive supernova explosion. While this event may be a long way off in our human timeline, it’s a blink of an eye in the vastness of the 13.8 billion-year-old cosmos.
The discovery of TIC 290061484 was made possible by the strobing starlight caused by the stars passing in front of each other, as seen from our perspective on Earth. Scientists utilized machine learning to analyze vast amounts of data from TESS, searching for patterns indicating these eclipses. Citizen scientists then played a crucial role in further filtering this data to identify interesting signals.
“We’re mainly looking for signatures of compact multi-star systems, unusual pulsating stars in binary systems, and weird objects,” said Saul Rappaport, a physics professor at the Massachusetts Institute of Technology (MIT) and part of the Visual Survey Group. “It’s exciting to identify a system like this because they’re rarely found, but they may be more common than current tallies suggest.”
The team believes that many more systems like this are likely hidden within the Milky Way, waiting to be discovered. Some may even have even shorter orbits than the stars of the TIC 290061484 system.
While current technology may struggle to spot these tightly bound triple stars, the upcoming launch of the Nancy Grace Roman Space Telescope (Roman), scheduled for no earlier than May 2027, promises to revolutionize our understanding of these systems.
Roman will capture significantly more detailed images of space than TESS, providing a “zoomed-in” view of the cosmos. This enhanced capability will allow Roman to peer deep into the heart of the Milky Way, where stars are densely packed together, giving us a never-before-seen glimpse into the nature of star systems within our galaxy.
One of Roman’s primary missions will be to monitor the light from hundreds of millions of stars, searching for the tell-tale strobing effect that revealed TIC 290061484. This will enable scientists to uncover hidden star systems with even shorter orbital periods, pushing the boundaries of our understanding of these intricate celestial dances.
Roman may even unveil star systems with more than three stars, perhaps as many as six, tightly packed together like bees in a hive. “Before scientists discovered triply eclipsing triple star systems, we didn’t expect them to be out there,” said Tamás Borkovits of the Baja Observatory in Hungary. “But once we found them, we thought, well, why not?”
The discoveries made possible by Roman could revolutionize our understanding of star system formation and evolution. It promises to unveil a hidden universe of celestial wonders, pushing the boundaries of our understanding of the cosmos and revealing secrets that have been hidden for eons. The research team’s findings were published in the Astrophysical Journal.
