Datasets:

juliensimon
/

aavso-vsx-variable-stars

license: cc-by-4.0
pretty_name: AAVSO Variable Star Index (VSX)
language:
  - en
description: >-
  AAVSO Variable Star Index (VSX) catalog with 10,300,820 variable stars
  including types, periods, magnitudes, and spectral classifications.
task_categories:
  - tabular-classification
  - tabular-regression
tags:
  - space
  - variable-stars
  - aavso
  - vsx
  - astronomy
  - open-data
  - tabular-data
size_categories:
  - 1M<n<10M
configs:
  - config_name: default
    data_files:
      - split: train
        path: data/aavso_vsx_variable_stars.parquet
    default: true

AAVSO Variable Star Index (VSX)

Part of the Astronomy Datasets collection on Hugging Face.

The AAVSO Variable Star Index (VSX) is the most comprehensive catalog of variable stars, containing 10,300,820 entries with variable star classifications, photometric properties, periods, and spectral types. VSX is maintained by the American Association of Variable Star Observers and is the standard reference for variable star research.

Dataset description

VSX aggregates variable star data from hundreds of surveys and catalogs worldwide including OGLE, ASAS-SN, ZTF, Gaia, and AAVSO observer submissions. Each entry represents a unique variable or suspected variable star with its variability type, brightness range, period (if known), epoch, and spectral classification.

Of the 10,300,820 entries, 4,830,314 have a measured period and 10,292,210 have a variability classification.

Key columns

Column	Type	Description
`aavso_uid`	Int64	AAVSO unique object identifier
`name`	string	Primary designation
`ra_deg`	float64	Right ascension J2000 (degrees)
`dec_deg`	float64	Declination J2000 (degrees)
`variable_type`	string	Variability type (e.g., EW, SR, RRAB, DSCT)
`var_flag`	Int64	Variability flag (0=confirmed, 1=suspected)
`mag_max`	float64	Maximum brightness (magnitude at max light)
`mag_max_passband`	string	Passband for max magnitude
`mag_min`	float64	Minimum brightness / amplitude
`mag_min_passband`	string	Passband for min magnitude
`min_is_amplitude`	string	Y if mag_min is amplitude, not absolute magnitude
`period_days`	float64	Period in days
`epoch_jd`	float64	Epoch of maximum/minimum (Julian Date)
`spectral_type`	string	Spectral classification
`mag_range`	float64	Derived magnitude range (mag_min - mag_max)

Full schema includes 22 columns with uncertainty flags and limit flags.

Top variability types

Type	Count
`ROT`	2,352,208
`E`	1,987,833
`L`	1,604,633
`RS`	719,268
`DSCT	GDOR
`S`	493,290
`EW`	397,843
`SR`	323,058
`VAR`	310,300
`RRAB`	189,791

Quick stats

10,300,820 variable star entries
4,830,314 with measured period (46.9%)
10,292,210 with variability classification (99.9%)
RA range: 0.0001 to 360.0000 degrees
Dec range: -89.9288 to 89.9038 degrees

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/aavso-vsx-variable-stars", split="train")
df = ds.to_pandas()

# Eclipsing binaries with known periods
eclipsing = df[df["variable_type"].str.startswith("E", na=False) & df["period_days"].notna()]
print(f"Eclipsing binaries with periods: {len(eclipsing):,}")

# Period-amplitude diagram for RR Lyrae
rrab = df[df["variable_type"] == "RRAB"]
import matplotlib.pyplot as plt
plt.scatter(rrab["period_days"], rrab["mag_range"], s=0.5, alpha=0.3)
plt.xlabel("Period (days)")
plt.ylabel("Amplitude (mag)")
plt.title("RR Lyrae (RRAB) Period-Amplitude Diagram")
plt.show()

# Sky distribution
plt.hexbin(df["ra_deg"], df["dec_deg"], gridsize=200, mincnt=1)
plt.colorbar(label="Star count")
plt.xlabel("RA (deg)")
plt.ylabel("Dec (deg)")
plt.title("VSX Variable Stars Sky Density")
plt.show()

Data source

Watson, C.L., Henden, A.A., & Price, A. (2006), The International Variable Star Index (VSX). Society for Astronomical Sciences 25th Annual Symposium on Telescope Science, p. 47. Maintained by AAVSO: https://www.aavso.org/vsx/

Pipeline

Source code: juliensimon/space-datasets

Citation

@dataset{aavso_vsx_variable_stars,
  author = {Simon, Julien},
  title = {AAVSO Variable Star Index (VSX)},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/aavso-vsx-variable-stars},
  note = {Based on AAVSO VSX (Watson et al. 2006)}
}

License

CC-BY-4.0