A modeling study of the Solar Neighborhood suggests that star formation came in bursts, followed by a delayed, smoother history of core-collapse supernovae (ccSNe)—the explosions the model associates with candidate progenitor stars of at least 8 solar masses.
In the most recent 0–15 million years, the reconstructed map showed strong enhancements toward Orion, Vela, Sco-Cen and Cepheus, often overlapping cavities and shells seen in present-day maps.
The work is an arXiv v1 preprint dated 20 August 2026; no journal publication is reported.
A history written backward
The map should be read as the clustered component of recent ccSN activity recoverable from surviving young clusters, rather than a complete account of every local explosion.
The researchers selected 568 clusters younger than 100 million years from a 2.5-kiloparsec cube around the Sun. Rate and clustering analyses used a nested 1-kiloparsec sample of 312 clusters.
Using Gaia-based cluster properties, the team integrated the clusters’ three-dimensional motions backward through an assumed axisymmetric Galactic potential—a simplified model of the Milky Way’s gravitational field—and combined those paths with stellar-mass sampling and lifetimes to estimate when and where ccSNe might have occurred over 50 million years.
For each cluster, the model generated 100 possible stellar populations using a Kroupa initial-mass function, a way of representing the spread of stellar masses from 0.03 to 120 solar masses. Stars with initial masses of at least 8 solar masses were counted as candidate ccSN progenitors.
The map changes with time
At earlier lookback times, the emphasis shifted: the map was dominated by enhancements associated with the Collinder 135, Messier 6 and Alpha Persei cluster families.
Vela was the most prominent recent enhancement. Inside the study’s contour corresponding to 17 reconstructed events per million years per square kiloparsec, the model placed 41 ccSNe over the past 15 million years, with a +7/−7 interval.
A concentrated pattern
A nearest-neighbor test compared the reconstructed events with randomized cluster placements. For events in different host clusters, the ratio was about 1.5–1.6 over the last 20 million years and 1.8–2.2 from 20 to 50 million years ago.
When same-cluster pairs were included, the corresponding ratios were about 1.5 over the last 20 million years and 1.3–1.6 from 20 to 50 million years ago. The comparison indicated stronger clustering in the reconstructed history.
Rates with an unresolved scale
Across the last 40 million years, the mean reconstructed star-formation rate was 823 solar masses per million years, while the mean ccSN rate was 7.7 events per million years. Scaled to a Milky Way-equivalent figure, that became 0.55 ± 0.03 events per century.
The comparison with present-day OB-star catalogues did not settle that normalization. The catalogues ranged from rates similar to the cluster reconstruction to rates several times higher; the table lists rate entries of 0.71 for Q25 and 2.78 for ALS III.
The authors did not rescale the ccSN map because the catalogues overlap weakly and require different corrections. The absolute normalization therefore remains uncertain even where the reconstructed pattern is clear.
What the reconstruction can—and cannot—show
Because the map recovers only the clustered component represented by surviving young clusters, it can miss activity from populations that dispersed or dissolved. The reported rates should not be read as a complete local ccSN census.
The study maps spatial overlaps between reconstructed recent activity and present-day cavities and shells. It provides a reconstruction and comparison, not proof that the inferred explosions created any particular structure.
Paper data and sources
Original title: The Nearby Star Formation and Supernova Histories Reconstructed from Young Star Clusters
Authors: Cameren Swiggum, Catherine Zucker, Michelangelo Pantaleoni González et al.
Journal/Repository: arXiv
Status: Preprint, not yet peer-reviewed
First online: 2026-08-20
DOI: Not available
Original paper · Full text