juliensimon/gaia-dr3-young-stellar-objects

Gaia DR3 Young Stellar Objects

Part of the Astronomy Datasets collection on Hugging Face.

The Gaia DR3 young stellar object (YSO) catalog, containing 79,375 YSO candidates identified by the ESA Gaia mission's variability classification pipeline. Each source includes a YSO classification confidence score, variability statistics (amplitudes, standard deviations, skewness, kurtosis), astrometry (positions, parallax, proper motions), and multi-band photometry (G, BP, RP).

Dataset description

Young stellar objects are pre-main-sequence stars still in the process of forming, often surrounded by circumstellar disks and exhibiting irregular photometric variability. Gaia's all-sky photometric survey identified these candidates through automated variability classification in the vari_classifier_result table. The best_class_score field gives the classifier's confidence for the YSO label (higher = more confident).

This dataset joins three Gaia DR3 tables:

• vari_classifier_result — YSO classification and confidence score
• vari_summary — variability statistics (mean/median magnitudes, amplitudes, scatter)
• gaia_source — astrometry (ra, dec, parallax, proper motion) and catalog photometry

Key columns

Column	Type	Description
source_id	int64	Gaia DR3 unique source identifier
best_class_name	string	Classification label (always "YSO" in this dataset)
best_class_score	float64	Classification confidence score (0-1)
ra	float64	Right ascension (deg, ICRS, epoch 2016.0)
dec	float64	Declination (deg, ICRS, epoch 2016.0)
l	float64	Galactic longitude (deg)
b	float64	Galactic latitude (deg)
parallax	float64	Parallax (mas)
parallax_error	float64	Parallax uncertainty (mas)
pmra	float64	Proper motion in RA (mas/yr)
pmdec	float64	Proper motion in Dec (mas/yr)
phot_g_mean_mag	float64	G-band mean magnitude (catalog)
median_mag_g_fov	float64	Median G-band magnitude (variability)
median_mag_bp	float64	Median BP-band magnitude (variability)
median_mag_rp	float64	Median RP-band magnitude (variability)
bp_rp	float64	BP-RP color index (derived)
std_dev_mag_g_fov	float64	G-band magnitude standard deviation
trimmed_range_mag_g_fov	float64	G-band variability amplitude
skewness_mag_g_fov	float64	G-band magnitude skewness
kurtosis_mag_g_fov	float64	G-band magnitude kurtosis
num_selected_g_fov	Int32	Number of G-band observations used

Full schema includes 40 columns with variability metrics and photometric parameters.

Quick stats

• 79,375 YSO candidates
• Median G magnitude: 16.99
• Median classification score: 0.512

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/gaia-dr3-young-stellar-objects", split="train")
df = ds.to_pandas()

# Classification score distribution
print(df["best_class_score"].describe())

# High-confidence YSOs (score > 0.5)
confident = df[df["best_class_score"] > 0.5]
print(f"High-confidence YSOs: {len(confident):,}")

# Color-magnitude diagram
import matplotlib.pyplot as plt
plt.scatter(df["bp_rp"], df["phot_g_mean_mag"], s=1, alpha=0.3, c=df["best_class_score"], cmap="viridis")
plt.colorbar(label="Classification score")
plt.xlabel("BP - RP (mag)")
plt.ylabel("G (mag)")
plt.gca().invert_yaxis()
plt.title("Gaia DR3 YSO Color-Magnitude Diagram")
plt.show()

Data source

Gaia Collaboration (2023), Gaia Data Release 3: variability processing and analysis results. European Space Agency. Via ESA Gaia Archive — joined from gaiadr3.vari_classifier_result, gaiadr3.vari_summary, and gaiadr3.gaia_source.

Related datasets

• Gaia DR3 Eclipsing Binaries — Gaia eclipsing binary candidates
• Gaia DR3 Variable Star Summary — all Gaia variable star classifications

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_young_stellar_objects,
  author = {Simon, Julien},
  title = {Gaia DR3 Young Stellar Objects},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/gaia-dr3-young-stellar-objects},
  note = {Based on Gaia DR3 (ESA)}
}

License

CC-BY-4.0