Astronomers confirm a faint third planet in the Beta Pictoris system

Astronomers have confirmed a third giant planet orbiting the young star Beta Pictoris after combining new observations with more than a decade of archived telescope data.

The discovery was announced July 15, 2026, through two independent research efforts. A team using the European Southern Observatory’s Very Large Telescope identified the planet with the ERIS instrument and traced its movement through earlier observations. A separate team using NASA’s James Webb Space Telescope identified the planet through moderate-resolution spectroscopy, finding atmospheric signatures that helped distinguish it from dust and stellar glare. NASA’s report was last updated July 16.

Beta Pictoris is about 63 light-years from Earth and roughly 23 million years old. The newly confirmed planet, Beta Pictoris d, is estimated at approximately 2.4 Jupiter masses, plus or minus 0.6 Jupiter masses, in the ESO-linked study. The Webb team reported a broader estimate of about two to four Jupiter masses.

How the planet was confirmed

The ESO team first identified Beta Pictoris d in observations made with ERIS, a high-contrast imaging instrument on the Very Large Telescope. Researchers then searched archival data, including observations from the VLT’s SPHERE instrument and Webb’s NIRCam camera.

Those earlier images did not make the planet easy to identify. The world lies close to its bright star and within a dusty debris disk that scatters light. But repeated observations showed a changing position consistent with orbital motion over a baseline of about 11 years.

This is direct imaging, a method that attempts to separate a planet’s own faint light from the glare of its star. It differs from the transit method, which detects a temporary dip in starlight when a planet crosses in front of its star.

What Webb found in the atmosphere

The independent Webb study used moderate-resolution spectroscopy rather than relying only on a bright point in a conventional image. Webb’s NIRSpec instrument found a distinctive pattern of carbon-monoxide absorption features in the planet’s spectrum.

The spectrum also allowed researchers to measure radial velocity, or motion along the line of sight. The object’s speed, position and alignment with the debris disk were consistent with a planet orbiting Beta Pictoris rather than a background star or another unrelated source. Follow-up observations with Webb’s MIRI instrument detected water vapor and methane, adding further evidence of the planet’s identity and providing more information about its atmosphere.

Why Beta Pictoris d is difficult to see

Beta Pictoris d is roughly 100 times fainter than the system’s better-known planet, Beta Pictoris b. ESO described it as the faintest exoplanet directly imaged from Earth in its comparison after correcting for distance, and as one of the lightest exoplanets imaged from the ground.

The system is only about 23 million years old, so its planets remain relatively warm from formation and can emit detectable infrared light. Even so, the star’s brightness and the debris disk make high-contrast observation difficult. The new result shows why improved instruments and long-term archival searches can work together: a planet that was present in older data may become identifiable only after better observations reveal its motion and atmospheric properties.

What the planet may reveal about the system

Beta Pictoris d follows a wider orbit of roughly 30 astronomical units, near the region occupied by Neptune in our solar system. Its position and estimated mass are consistent with models in which the planet may help shape the inner edge or other structures in the system’s debris disk.

That connection remains a model-based interpretation, not settled proof that the planet alone created the disk’s observed features. But adding a third giant planet gives astronomers a stronger system in which to study how multiple planets and debris evolve together. Beta Pictoris is now only the second known system with more than two directly imaged planets, after HR 8799.

What comes next

Researchers will continue analyzing the Webb observations and the planet’s orbit. Future instruments, including the European Southern Observatory’s Extremely Large Telescope, may extend this approach to fainter and lower-mass planets.

Beta Pictoris d cannot be visited with current technology. Its importance is scientific: the discovery demonstrates how atmospheric chemistry, orbital motion, direct imaging and old observations can combine to identify a distant gas giant that had remained difficult to separate from its star and surrounding dust.

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