Two planets-in-formation discovered around young star WISPIT 2
In the disk surrounding the young star WISPIT 2, not one but two planets are taking shape. Leiden PhD candidate Richelle van Capelleveen played a key role in this discovery, providing a rare glimpse into the early stages of planetary system formation.
Van Capelleveen had already discovered the first planet in the WISPIT 2 system. In the new study, published in The Astronomical Journal, observations with telescopes from the European Southern Observatory (ESO) confirmed the presence of a second planet. The disk’s unique structure shows remarkable similarities to a young solar system.
‘A window into our own past’
The WISPIT 2 system is only the second system—after PDS 70—where astronomers have directly observed two planets still in formation. WISPIT 2, however, has a much larger disk with striking gaps and rings. ‘These structures suggest that more planets are forming, which we may detect in the near future,’ says lead author Chloe Lawlor from the University of Galway. ‘WISPIT 2 gives us a window into our own past.’
Co-author Christian Ginski (University of Galway) adds: ‘WISPIT 2 is a unique cosmic laboratory where we can observe the formation of an entire planetary system.’ Observations like these help astronomers understand how young planetary systems evolve into mature systems like our own.
Two gas giants in the making
The first newborn planet in the system, WISPIT 2b, was discovered last year. With nearly five times the mass of Jupiter, it orbits its star at roughly sixty times the Earth–Sun distance. ‘The discovery of this planet-in-the-making demonstrates what our current instruments are capable of,’ says Van Capelleveen.
Follow-up observations with ESO’s Very Large Telescope (VLT) and the VLT Interferometer (VLTI) confirmed that a second object is also a planet. This new planet, WISPIT 2c, orbits four times closer to the star and has about twice the mass of WISPIT 2b. Both planets are gas giants, similar to the outer planets of our solar system.
To confirm the existence of WISPIT 2c, the team used ESO’s SPHERE instrument on the VLT and the GRAVITY+ instrument on the VLTI.
A potential third planet?
Both planets occupy prominent gaps in the star’s dust disk. These gaps form as a direct consequence of the planets’ growth: particles in the disk accumulate, and their increasing gravitational pull draws in more material, eventually forming a planetary ‘embryo’. The remaining material around each gap forms the characteristic dust rings in the disk.
Beyond the gaps containing the two planets, astronomers have identified at least one smaller gap further out in WISPIT 2’s disk. ‘We suspect a third planet carved this gap,’ says Lawlor. ‘Its narrower, shallower appearance suggests it is relatively small—likely no more massive than Saturn.’
The team plans to conduct follow-up observations soon. With the upcoming Extremely Large Telescope, astronomers may eventually be able to image such a planet directly.
Scientific paper
Chloe Lawlor et al. (2026). Direct spectroscopic confirmation of the young embedded proto-planet WISPIT 2c. Astrophysical Journal.
Header image: VLT images of two planets-in-formation around the young star WISPIT 2. Credit: ESO/C. Lawlor, R. F. van Capelleveen et al.
This press release was originally published on astronomie.nl