From Star Wars Fantasy to Real Science
Fans of the galaxy‑far‑away have long imagined worlds like Tatooine—planets that circle two suns. Until recently, astronomers could only spot such double‑star planets when their orbits aligned perfectly with Earth’s line of sight, a geometric lottery that yielded a modest tally of fourteen candidates. A research team from Australia, however, rewrote the rule book by looking for the subtle gravitational tug a planet exerts on its host stars, rather than trying to see the planet itself.
How a Tiny Pull Becomes a Detectable Signal
The idea hinges on eclipsing binary stars, pairs that periodically pass in front of each other. In a pristine binary system, the timing of each eclipse follows an exact rhythm. Introduce a third body—a planet—and the gravitational pull distorts the stars’ orbit just enough to shift the eclipse schedule by a few minutes over years. By measuring those minute drifts, scientists can infer the presence of an unseen companion.
Mining TESS Data for the Unseen
The team sifted through roughly 1,600 observations gathered by NASA’s Transiting Exoplanet Survey Satellite (TESS). After eliminating systems whose timing irregularities could be explained by stellar activity or measurement noise, 36 binaries remained with unexplained “wiggles.” Of those, 27 exhibited patterns consistent with the influence of a planetary-mass object.
Most of the inferred worlds appear to be lighter than Jupiter, with a handful potentially as massive as Neptune. If confirmed, these would set a new record as the lightest planets discovered around double‑star systems. Six other candidates showed signals that are likely too massive for planets, pointing instead to brown dwarfs or low‑mass stars.
Next Steps: From Candidates to Confirmed Planets
While the gravitational timing method offers a powerful first glance, definitive proof requires the radial‑velocity technique—measuring how the binary stars wobble under the planet’s pull. Luckily, all 27 systems are bright enough for ground‑based telescopes to perform such follow‑up studies.
Beyond the immediate discoveries, the researchers note that the catalog they examined contains more than two million double‑star systems. Statistically, hundreds more Tatooine‑like worlds likely await detection, hidden in the data but awaiting a clever method to coax them out.
So far, the sky‑watchers have turned a sci‑fi dream into an empirical reality, proving that planets orbiting twin suns are not just a cinematic flourish but a common outcome of star formation.
Source: https://scientias.nl/astronomen-vinden-27-nieuwe-tatooine-werelden-zonder-ze-ooit-te-hebben-gezien/