Datasets:
license: cc-by-4.0
pretty_name: Open Star Clusters (Hunt & Reffert 2024)
language:
- en
description: >-
The most comprehensive Gaia-era catalog of open star clusters from Hunt &
Reffert (2024). Sourced via VizieR CDS Strasbourg.
task_categories:
- tabular-classification
tags:
- space
- star-cluster
- open-cluster
- gaia
- astronomy
- open-data
size_categories:
- 1K<n<10K
Open Star Clusters (Hunt & Reffert 2024)
The most comprehensive Gaia-era catalog of open star clusters, containing 7,167 clusters with positions, distances, ages, and membership counts derived from Gaia DR3.
Dataset description
Open clusters are gravitationally bound groups of stars that formed together from the same molecular cloud. They are key tracers of Galactic structure, stellar evolution, and the chemical enrichment history of the Milky Way disk. This catalog from Hunt & Reffert (2024) represents the most complete census of open clusters in the Gaia era, combining automated detection with careful validation.
Each entry includes sky coordinates, distance, parallax, age, extinction, number of members, and radial velocity where available.
Schema
| Column | Type | Description |
|---|---|---|
ra_deg |
float64 | Right ascension J2000 (degrees) |
dec_deg |
float64 | Declination J2000 (degrees) |
distance_pc |
float64 | Distance (parsecs) |
parallax_mas |
float64 | Parallax (milliarcseconds) |
log_age |
float64 | Logarithmic age (log10 years) |
extinction_av |
float64 | Visual extinction A_V (mag) |
n_members |
float64 | Number of identified members |
radial_velocity_kms |
float64 | Radial velocity (km/s) |
Quick stats
- 7,167 open clusters
- 0 with age estimates
- 5,749 with radial velocities
Usage
from datasets import load_dataset
ds = load_dataset("juliensimon/open-star-clusters", split="train")
df = ds.to_pandas()
# Nearby clusters (< 500 pc)
nearby = df[df["distance_pc"] < 500].sort_values("distance_pc")
print(f"{len(nearby):,} clusters within 500 pc")
# Young clusters (< 10 Myr)
young = df[df["log_age"] < 7.0]
print(f"{len(young):,} clusters younger than 10 Myr")
Data source
Hunt, E.L. & Reffert, S. (2024), "Improving the open cluster census. III. Using Gaia DR3", A&A, 686, A42. Accessed via VizieR, CDS Strasbourg.
Related datasets
- gcvs-variable-stars -- General Catalogue of Variable Stars
- pulsar-catalog -- ATNF Pulsar Catalogue
Pipeline
Source code: juliensimon/space-datasets
Citation
@dataset{open_star_clusters,
author = {Simon, Julien},
title = {Open Star Clusters (Hunt & Reffert 2024)},
year = {2026},
publisher = {Hugging Face},
url = {https://huggingface.co/datasets/juliensimon/open-star-clusters},
note = {Based on Hunt & Reffert (2024), A&A, 686, A42 via VizieR CDS Strasbourg}
}