juliensimon/gaia-dr3-spectroscopic-binaries

Gaia DR3 Spectroscopic Binary Stars

Credit: NASA/ESA/Hubble

Part of the Astronomy Datasets collection on Hugging Face.

Orbital solutions for 185,957 spectroscopic binary stars from the ESA Gaia Data Release 3 non-single stars (NSS) pipeline -- 181,327 single-lined (SB1) and 4,630 double-lined (SB2) systems with full Keplerian orbital parameters.

Dataset description

Spectroscopic binaries are star systems where the binary nature is revealed not by eclipses or visual separation, but by periodic Doppler shifts in the stellar spectral lines as the stars orbit their common center of mass. In a single-lined spectroscopic binary (SB1), only one star's spectrum is visible -- the companion is too faint or its lines are blended -- and the radial velocity curve of the primary yields the orbital period, eccentricity, and the mass function f(m), which places a lower limit on the companion mass. In a double-lined spectroscopic binary (SB2), both stars contribute detectable spectral lines, and the two radial velocity curves provide the mass ratio directly, constraining individual masses when combined with inclination estimates.

The orbital elements in this catalog -- period, eccentricity, argument of periastron, velocity semi-amplitudes (K1, K2), and systemic velocity -- are the fundamental observables for binary star physics. They enable measurements of stellar masses (the single most important parameter governing stellar evolution), tests of tidal circularization theory (short-period binaries are expected to have circular orbits due to tidal dissipation), and identification of compact companions such as white dwarfs, neutron stars, and stellar-mass black holes lurking in otherwise unremarkable systems.

Gaia's contribution is transformative. The Radial Velocity Spectrometer (RVS) aboard Gaia has obtained multi-epoch radial velocities for millions of stars brighter than about G ~ 12, and the non-single stars pipeline has fitted Keplerian orbits to those showing statistically significant radial velocity variability. The resulting catalog of over 185,957 spectroscopic binary orbits is an order of magnitude larger than any previous compilation -- the Ninth Catalogue of Spectroscopic Binary Orbits (SB9) contained fewer than 4,000 systems accumulated over a century of ground-based observations. This leap in sample size enables population-level studies of binary orbital properties (period distribution, eccentricity-period relation, mass-ratio distribution) across a wide range of spectral types, metallicities, and Galactic environments that were previously inaccessible.

The period-eccentricity diagram of these systems traces the physics of tidal evolution: systems with periods below roughly 10 days are expected to have been circularized by tidal friction, while longer-period systems retain the eccentricity imprinted at formation. The transition between these regimes is a sensitive probe of stellar interior structure and the efficiency of dissipative processes. Similarly, the distribution of mass functions and mass ratios encodes the initial mass function of binary companions and the physics of binary star formation -- whether companions are drawn randomly from the IMF or preferentially paired with similar-mass primaries.

Schema

Column	Type	Description
solution_id	int	Solution id
source_id	string	Gaia DR3 unique source identifier
ra_deg	float64	Right ascension ICRS (degrees)
dec_deg	float64	Declination ICRS (degrees)
period_days	float64	Orbital period (days)
period_days_err	float64	Period days err
t_periastron	float64	Time of periastron passage (BJD)
t_periastron_err	float64	T periastron err
ecc	float64	Orbital eccentricity
eccentricity_err	float64	Eccentricity err
center_of_mass_velocity	float64	Center-of-mass velocity (km/s)
center_of_mass_velocity_err	float64	Center of mass velocity err
semi_amplitude_k1	float64	Semi amplitude k1
semi_amplitude_k1_err	float64	Semi amplitude k1 err
omega	float64	Omega
omega_err	float64	Omega err
nrvp	int	Nrvp
ng_rvp	int	Ng rvp
nrvs	int	Nrvs
ng_rvs	int	Ng rvs
bit_index	int	Bit index for solution flags
corvec0	float64	Corvec0
corvec1	float64	Corvec1
corvec2	float64	Corvec2
corvec3	float64	Corvec3
corvec4	float64	Corvec4
corvec5	float64	Corvec5
corvec6	float64	Corvec6
corvec7	float64	Corvec7
corvec8	float64	Corvec8
corvec9	float64	Corvec9
corvec10	float64	Corvec10
corvec11	float64	Corvec11
corvec12	float64	Corvec12
corvec13	float64	Corvec13
corvec14	float64	Corvec14
obj_func	float64	Objective function value
goodness	float64	Goodness
eff	float64	Eff
signi	float64	Signi
flags	int	Flags
conf_persp	float64	Conf persp
solution_type	string	NSS solution type (SB1 = single-lined, SB2 = double-lined)

Quick stats

• 185,957 spectroscopic binary orbital solutions
• 181,327 single-lined (SB1) systems
• 4,630 double-lined (SB2) systems
• Period range: 0.2500 to 1451.96 days (median 118.5825)
• Median eccentricity: 0.193 (24,835 near-circular with e < 0.05)
• 43 columns with orbital, photometric, and astrometric parameters

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/gaia-dr3-spectroscopic-binaries", split="train")
df = ds.to_pandas()

# SB1 vs SB2 breakdown
print(df["solution_type"].value_counts())

# Period-eccentricity diagram (tidal circularization)
import matplotlib.pyplot as plt
period_col = [c for c in df.columns if "period" in c][0]
ecc_col = [c for c in df.columns if "eccentric" in c or c == "ecc"][0]
valid = df.dropna(subset=[period_col, ecc_col])
plt.scatter(valid[period_col], valid[ecc_col], s=0.3, alpha=0.3)
plt.xscale("log")
plt.xlabel("Period (days)")
plt.ylabel("Eccentricity")
plt.title("Gaia DR3 Spectroscopic Binaries: Period vs Eccentricity")
plt.show()

# High-eccentricity systems
high_ecc = df[df[ecc_col] > 0.8]
print(f"{len(high_ecc):,} systems with eccentricity > 0.8")

Data source

Gaia Collaboration, Arenou, F. et al. (2023), Gaia Data Release 3: stellar multiplicity, a teaser for the hidden treasure. Astronomy & Astrophysics, 674, A34. European Space Agency, accessed via VizieR CDS Strasbourg (I/357) and/or the Gaia Archive.

Update schedule

Static dataset -- uploaded once from Gaia DR3. Will be updated when Gaia DR4 is released.

Related datasets

• wds-double-stars -- Washington Double Star Catalog
• gaia-dr3-eclipsing-binaries -- Gaia DR3 Eclipsing Binaries
• kepler-eclipsing-binaries -- Kepler Eclipsing Binary Catalog
• xray-binary-catalog -- X-ray Binary Catalog

Pipeline

Source code: juliensimon/space-datasets

Support

If you find this dataset useful, please give it a ❤️ on the dataset page and share feedback in the Community tab! Also consider giving a ⭐️ to the space-datasets repo.

Citation

@dataset{gaia_dr3_spectroscopic_binaries,
  author = {Simon, Julien},
  title = {Gaia DR3 Spectroscopic Binary Stars},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/gaia-dr3-spectroscopic-binaries},
  note = {Based on Gaia DR3 (Arenou et al. 2023, A&A 674, A34) via VizieR CDS Strasbourg}
}

License

CC-BY-NC-3.0-IGO