Artistic representation of TOI-2267. Credit: Mario Sucerquia / Univ. Grenoble Alpes.
Astronomy may never look quite the same again. A team of astrophysicists in Andalucía has identified something that, until recently, many thought simply could not exist: three Earth-sized planets orbiting not one, but two stars at the same time.
The finding, now published in the journal Astronomy & Astrophysics, is already being described as a breakthrough moment in our understanding of how worlds are formed.
For decades, binary star systems – where two suns orbit each other – were viewed as too chaotic for planets to develop. The gravitational tug-of-war between both stars was believed to disrupt the kind of stable orbits necessary for planets to survive. In short, if a solar system had two suns, it wasn’t supposed to have planets like ours.
But nature has just rewritten the rulebook.
A Solar system that shouldn’t exist – but does
The system in question is called TOI-2267, located about 190 light-years away. At its centre are two small, cool stars – roughly classified as M-type dwarfs – orbiting extremely close together. To put it in perspective, the distance between the two stars is only eight times the distance between the Earth and our own Sun, which is incredibly compact by cosmic standards.
And yet, circling around these twin suns are three planets with sizes similar to Earth’s. They orbit on short, tight paths, meaning their “years” are much shorter than ours.
Francisco J. Pozuelos, one of the study’s co-leads at the Institute of Astrophysics of Andalucía (IAA-CSIC), describes TOI-2267 as “the most compact and cold binary system known to host Earth-sized planets.” What’s more, scientists were able to observe the planets passing in front of both stars, a rare and important confirmation that the planets really do orbit the pair, not just one of them.
This detail alone makes TOI-2267 something unique in the known universe.
It also challenges what many planetary scientists thought was possible. If planets can form in the gravitational chaos of a binary system this tight, then the range of environments where planets – and possibly life – could exist is suddenly much wider than expected.
Science with a strong Andalusian signature
Part of what’s making this discovery resonate is that it’s not just scientifically impressive – it’s also a home-grown achievement for Andalucía.
The research team relied heavily on technology developed at the IAA-CSIC, particularly a software tool called SHERLOCK. Designed to search through data from NASA’s TESS satellite (which monitors thousands of stars for signs of orbiting planets), SHERLOCK was key to spotting two of the planets before any other team in the world. That early detection gave the researchers more than a year’s head start in confirming the system.
From there, the team carried out follow-up observations using the Sierra Nevada Observatory and telescopes belonging to the SPECULOOS and TRAPPIST networks – international projects coordinated in part by the University of Liège.
Sebastián Zúñiga-Fernández, another co-author working with the team, notes that TOI-2267 now serves as “a natural testing ground for pushing the limits of planetary formation models.” In simpler terms, this system lets researchers ask questions they previously had no evidence to ask.
In the coming years, scientists plan to use more advanced tools – including the James Webb Space Telescope – to examine the planets’ atmospheres, densities and compositions. If even one of these planets turns out to have conditions favourable to liquid water, the conversation shifts from “possible worlds” to possible life.
A door opens to new possibilities
The emotional weight of the discovery lies in what it suggests: that the universe may be much more adaptable and inventive than we once believed.
For years, astronomers assumed that life-friendly planets needed calm, stable suns. TOI-2267 challenges that. It shows that even in environments we thought were too extreme, planets can form and survive.
This discovery does not prove life exists elsewhere. But it does expand the map of where life could be.
And in astronomy, expanding the map is everything.
