Mysterious red dot first spotted by U of A astronomers reveals itself as a baby planet orbiting a young star

A new planet has been confirmed in one of the youngest and most unusual solar systems ever discovered – and University of Arizona instrumentation set the stage for finding it.

The planetary system, known as WISPIT 2, was first unveiled in August 2025 when a team led by U of A astronomer Laird Close used the university's cutting-edge MagAO-X instrument to photograph a growing planet, WISPIT 2b, nestled inside a dark gap between dust rings surrounding a young star. The WISPIT system was originally discovered by Richelle van Capelleveen, a doctoral student at Leiden Observatory in the Netherlands. That discovery was the first confirmed detection of a protoplanet hiding inside a disk gap – a phenomenon long theorized but never before seen.

During the same observations, Close's team also spotted a second companion, dubbed "CC1," in an orbit closer to its host star than WISPIT 2b. CC1 appeared about 15 astronomical units from the star, roughly 1.5 times the distance between our sun and Saturn. 

"At the time of detection, we couldn't decipher the true nature of CC1 – it could have been a massive planet or simply a clump of dense, reddish dust," Close said. 

The WISPIT 2 system as captured by the Magellan Telescope in Chile and the University of Arizona's Large Binocular Telescope. The newly confirmed planet WISPIT 2c is the red dot below the star. The protoplanet WISPIT 2b appears as a small purple dot in a dust-free gap between a bright inner dust ring and a fainter outer ring.

Laird Close, University of Arizona

Graduate student Gabriel Weible at Steward Observatory helped investigate CC1 further using the Large Binocular Telescope on Mount Graham, detecting it clearly in thermal infrared light, but its true nature remained unresolved until now.

An international research team lead by Chloe Lawlor, a doctoral student in astrophysics at the University of Galway in Ireland, along with Close has now confirmed that CC1 is indeed a real planet, earning it the official designation WISPIT 2c. The finding makes WISPIT 2 only the second known young solar system with two confirmed giant planets orbiting within a multi-ringed disk.

WISPIT 2c is estimated to be around five million years old and approximately 10 times the mass of Jupiter, making it one of the most massive young planets ever directly characterized. It is twice the physical size of its sibling WISPIT 2b, yet orbits four times closer to the host star, placing it in a region of the disk that is exceedingly difficult to observe from Earth.

The confirmation came through the Very Large Telescope Interferometer in Chile's Atacama Desert, which links multiple large telescopes to function as a single, far more powerful instrument. To make the detection possible, the team used a newly developed extreme adaptive optics system, along with GRAVITY, a high-sensitivity spectro-interferometer operated by the European Southern Observatory, which helps enhance images from the VLTI through its ability to further resolve faint objects such as exoplanets. This combination of techniques was essential to resolving a source so close to its host star.

The team detected a distinctive chemical signature of carbon monoxide gas in the planet's atmosphere – a key marker of young, actively forming gas giants. The results are published in Astrophysical Journal Letters. 

"Carbon monoxide is one of the key signatures we look for in young giant planets. When we saw it clearly in the data, that was when we knew we had something significant," said Lawlor.  "WISPIT 2 will become an important laboratory to study planet formation." 

MagAO-X, the adaptive optics system behind that first discovery of CC1, was developed and built by Close and fellow U of A astronomer Jared Males, along with their students. One of the most powerful extreme adaptive optics systems in the world, it corrects for atmospheric distortion in real time, allowing telescopes to separate the faint glow of a young planet from the overwhelming brightness of its host star. The instrument is specifically tuned to detect planets in the optical part of the spectrum, making it uniquely suited for hunting protoplanets like those in the WISPIT 2 system. This, along with other U of A imaging and adaptive optics technology, laid the groundwork for this discovery.

The WISPIT 2 system – with its three dust rings, two confirmed giant planets, and a star similar in mass to our sun – offers astronomers a rare window into conditions resembling those of our own solar system’s earliest days, some 4.5 billion years ago. With U of A instrumentation at the heart of the original detection and with U of A astronomers continuing to collaborate in the ongoing study of the system, the discovery underscores the university's standing as a global leader in exoplanet science.

"By bringing together most of the largest optical and infrared telescopes on Earth, this exciting new solar system – with three rings and two massive planets – is now coming into better focus," Close said. "WISPIT 2 will be a benchmark exoplanetary system for years to come."