In the famous star system of Beta Pictoris, located just 63 light-years from Earth, astronomers have discovered another gas giant. This discovery, made in July 2026, was made possible by the combined efforts of the James Webb Space Telescope and ESO ground-based observatories. The new planet, named Beta Pictoris d, became the third in the system, which has long served as a laboratory for studying planet formation.
Beta Pic d is likely twice the mass of Jupiter, and the smallest of the three known giant planets in this system. It orbits at a distance of about 30 astronomical units, putting it somewhere around where Neptune is located in our own system.
The Beta Pictoris system, which is young at about 23 million years old, is surrounded by a bright disk of debris left over from planet formation. As early as 2008, the exoplanet Beta Pictoris b was directly photographed here for the first time – one of the first such "portraits" in history. A second planet, c, was found later. But a third had long eluded detection, hiding in the bright dust of the disk, which scatters the star's light and creates interference like a thick fog.
Beta Pic d was found while studying the atmosphere of Beta Pic b. An unexpected blob was spotted with the distinctive signature of carbon monoxide. The object’s speed, position, and alignment with the debris disk of the star made it clear it's not just a background object.
Two independent teams of scientists approached the task differently. A team led by Aidan Gibbs from the University of California, San Diego, worked with Webb data. They studied the atmosphere of the known planet b using the NIRSpec spectrograph in integral field unit (IFU) mode. Instead of looking for a bright spot, the researchers looked for chemical "fingerprints" – characteristic absorption lines of molecules in the spectrum. Unexpectedly, a carbon monoxide (CO) signal appeared in the data, which did not fit the dust picture. Its position, velocity, and alignment with the disk confirmed it was an orbiting planet.
In parallel, another group, led by Ben Saffiotti and Markus Bonse, used data from ESO's ground-based Very Large Telescope (VLT) with the ERIS instrument, as well as archival observations. They found the planet in images taken more than a decade ago, including those where it was barely visible next to b. It is one of the faintest exoplanets ever directly imaged from Earth: it is a hundred times fainter than planet b.
Beta Pictoris d is a gas giant with a mass of about 2–2.4 Jupiter masses, the lightest of the three known in the system. It orbits at a distance of approximately 26–30 AU from the star – wider than its siblings' orbits, but still within the inner edge of the debris disk. Scientists suggest that this planet helps shape the clear boundary of the disk by "sweeping up" material with its gravity.
The discovery is particularly notable because it demonstrates a new approach: spectroscopy allows planets to be "seen" through dust without relying solely on brightness. Webb detected traces of methane and water vapor in the planet's atmosphere, paving the way for detailed study of its composition. The Beta Pictoris system continues to surprise – astronomers now have another piece of the puzzle explaining how young planetary systems quickly acquire an ordered structure.
This is not the end of the story. Scientists plan further observations to more accurately determine the new planet's orbit, temperature, and chemistry. Each such step brings us closer to understanding how worlds around other stars are born and evolve – and perhaps, how typical our own Solar System is.
