Free Astronomy Magazine September-October 2026

35 SEPTEMBER-OCTOBER 2026 ASTRO PUBLISHING same planet using the James Webb Space Te- lescope (JWST), a facil- ity of the US, European and Canadian space agencies. Their results are also published in The Astrophysical Jour- nal Letters . To confirm a planet’s discovery from a detec- tion, astronomers usu- ally have to make fol- low-up observations. However, this system had been extensively studied, with several images stored in the ESO and JWST science archives. “To our joy, out it popped in previ- ous SPHERE observa- tions,” says Birkby, referring to another VLT instrument previ- ously used to observe the Beta Pictoris sys- tem. The planet was also spotted in archival observations from NIR- Cam, a JWST instru- ment. Now that the team knew where to look for the potential new planet, “it turns out it was hiding in the data all along!” says Birkby. Co-author Valentin Christiaens, re- searcher at CEA Paris-Saclay, France, adds: “The detections in the ar- chival SPHERE data are not only very exciting on their own, but also because they suggest a number of treasures are still hidden in the archives of VLT instruments!” Beta Pictoris is now the second sys- tem, after HR 8799, where more than two planets have been directly imaged. “Systems with multiple di- rectly imaged exoplanets are the ‘holy grails’ of discoveries, because A stronomers have discovered a third planet orbiting the star Beta Pictoris using ESO’s Very Large Telescope (VLT). The new planet, Beta Pictoris d, is among the lightest exoplanets ever to be imaged from the ground. After the initial discovery, the team found it had been hid- ing in archive observations spanning more than a decade. This video summarises the study. [ESO. Music: Stellardrone − To The Great Beyond. Written by: E. Elkington. Footage and photos: ESO, L. Calçada, M. Kornmesser, C. Malin, P. Horálek] https://www.youtube.com/watch?v=SeU_tE6yaz8 they can teach us a lot about what different exoplanets are like in the same formation environment,” says Sutlieff. Beta Pictoris d also clears up a mystery in its planetary system, as it has exactly the right mass and position to explain the particular shape of the surrounding debris disc, made of the leftovers of planet formation. The discovery of Beta Pictoris d in this way encourages further direct imaging of planetary systems where faint planets may have been hiding in plain sight, including with ESO’s upcoming Extremely Large Tele- scope (ELT). “Planets seem to have friends,” says Beth Biller, also a co-author of the paper and astronomer at the Uni- versity of Edinburgh, “many of the famous directly imaged exoplanet systems seem to have multiple giant planets in the same system, and likely there are even more lower mass planets hiding in these systems that might be revealed with instru- ments on the ELT.” !