51 Striking Images Show Dusty Rings Tracing Planet Formation Around Nearby Stars

VLT/SPHERE Reveals Diverse Debris Disks Around Young Stars

A team of astronomers has released a dramatic collection of 51 high-contrast images that reveal dusty rings and belts encircling young stars — direct signposts of planetary system evolution. Using the European Southern Observatory's Very Large Telescope (VLT) and its SPHERE instrument, researchers surveyed 161 nearby stars and resolved 51 debris-disk systems, producing one of the largest and most detailed atlases of circumstellar debris to date.

"This data set is an astronomical treasure," said Gaël Chauvin, co-author of the study and SPHERE project scientist. "It provides exceptional insights into the properties of debris disks, and allows for deductions of smaller bodies like asteroids and comets in these systems, which are impossible to observe directly."

Debris disks are created when leftover planetesimals — asteroids and comets — collide and grind down into fine dust. These dusty remnants are analogous to our Solar System's asteroid belt, Kuiper Belt and faint zodiacal dust, and they offer a snapshot of planetary systems after planets have largely formed but while dynamical sculpting is still underway.

How SPHERE Sees the Faint Dust

SPHERE makes these observations possible by dramatically reducing starlight so faint circumstellar material can be detected. A coronagraphic mask blocks the bright central star, adaptive optics correct for atmospheric turbulence in real time, and polarization filters increase sensitivity to starlight scattered by dust. Together, these techniques allow SPHERE to image disks typically in the first ~50 million years of a star's life.

Variety and Clues to Hidden Planets

The survey reveals a striking diversity of morphologies: narrow, sharply defined rings; broad diffuse belts; lopsided and asymmetric disks; and both edge-on and face-on orientations. Four of the disks were resolved at this level of detail for the first time. Examples highlighted by the team include HD 197481 and HD 39060, which show narrow streams of material in edge-on views, and nearly circular face-on rings around systems such as HD 109573 and HD 181327.

In many systems the dust is concentrated into sharply defined rings, strongly suggesting that unseen planets — especially giant planets — are sculpting the debris, much as Neptune sculpts our Kuiper Belt. Younger disks such as HD 145560 and HD 156623 appear more chaotic and billowy, indicating that planet-driven clearing and collisional evolution are still ongoing.

Population Trends and Future Follow-Up

Comparing structures across the sample, the team found clear trends: more massive host stars tend to host more massive disks, and disks with material concentrated farther from the star generally contain more mass. Features such as sharp inner edges and asymmetries in some images provide tantalizing hints of planets yet to be directly observed.

The SPHERE atlas will act as a roadmap for follow-up observations with next-generation facilities such as the James Webb Space Telescope and ESO's Extremely Large Telescope, which may directly detect the planets responsible for shaping these spectacular disks. The full study was published on Dec. 3 in the journal Astronomy & Astrophysics.