A Second Solar System Caught in the Act of Being Born
In the 437 light-years between Earth and a young star called WISP 2, astronomers have found something rare: a planetary family still under construction.
A team publishing in the Astrophysical Journal Letters reports that WISP 2 now harbors two confirmed gas giant planets, making it only the second embryonic solar system ever directly observed.
The first, PDS 70, was identified in 2018.
The discovery marks a pivotal shift in planetary science—from studying a single anomaly to beginning to see a pattern.
Jason Wang, an astronomer at Northwestern University not involved in the research, explained the significance: in astronomy, a sample size of one is considered an anomaly, but a sample size of two begins to suggest a population.
That transition—from lonely outlier to the beginning of a pattern—matters enormously for understanding whether our own solar system's formation was typical or a cosmic oddity.
Two Giants and the Hint of a Third
Last year, the same group revealed that WISP 2 contained at least one protoplanet carving through its protoplanetary disk of gas and dust—the first time astronomers had directly imaged a still-forming planet.
Now they've spotted a second gas giant, roughly ten times Jupiter's mass, also embedded in the swirling ring of material surrounding the infant star.
But the real intrigue lies farther out.
The astronomers have identified a third gap in WISP 2's disk, smaller and more distant than the others—a structure that suggests matter has already begun collapsing into a Saturn-sized world.
The team expects the European Southern Observatory's Extremely Large Telescope, currently under construction in Chile, will eventually be powerful enough to photograph that third candidate directly.
A Young Researcher's Breakthrough
The observations come from the Very Large Telescope in Chile's Atacama Desert.
Chloe Lawlor, a Ph.D. student at the University of Galway in Ireland, led the study.
She expressed surprise at the magnitude of the find. There is often a lot of self-doubt for people at her career stage, she noted. She hopes this discovery helps others realize that while they might not know it all yet, they still know enough to do big things.
What Comes Next
By studying WISP 2 alongside PDS 70 and whatever other embryonic systems emerge, researchers hope to tighten their grasp on the processes that shaped our own cosmic neighborhood billions of years ago.
Each new discovery adds a data point to a growing picture—one that may eventually reveal whether our solar system is ordinary or extraordinary in the universe's planet-making repertoire.
Based on: WISP 2 Embryonic Planetary System Discovery; Lawlor, C. et al.; The Astrophysical Journal Letters, 2024.