juliensimon/gswlc-galaxy-properties
GSWLC-2 Galaxy Properties Part of the Astronomy Datasets collection on Hugging Face. 659,229 galaxies with physical properties derived from UV-to-infrared spectral energy distribution (SED) fitting. GSWLC-2 (GALEX-SDSS-WISE Legacy Catalog 2) combines ultraviolet photometry from GALEX, optical photometry from SDSS, and mid-infrared photometry from WISE to estimate stellar masses, star formation rates, and dust attenuation for galaxies at redshifts 0.01 < z < 0.30.… See the full description on the dataset page: https://huggingface.co/datasets/juliensimon/gswlc-galaxy-properties.
GSWLC-2 Galaxy Properties
Part of the [Astronomy Datasets](https://huggingface.co/collections/juliensimon/astronomy-datasets-69c24caf2f17e36128946743) collection on Hugging Face.
659,229 galaxies with physical properties derived from UV-to-infrared spectral energy distribution (SED) fitting. GSWLC-2 (GALEX-SDSS-WISE Legacy Catalog 2) combines ultraviolet photometry from GALEX, optical photometry from SDSS, and mid-infrared photometry from WISE to estimate stellar masses, star formation rates, and dust attenuation for galaxies at redshifts 0.01 < z < 0.30.
Dataset description
The GSWLC is the definitive catalog for physical properties of low-redshift galaxies, covering ~90% of the SDSS spectroscopic footprint. Version 2 (Salim et al. 2018) incorporates WISE mid-IR photometry to better constrain dust-obscured star formation. The "X" variant (GSWLC-X2) is the master catalog that selects the deepest available UV observation for each galaxy from the A (shallow), M (medium), and D (deep) sub-catalogs.
Physical properties are derived using the CIGALE SED fitting code with Bayesian estimation of stellar mass, star formation rate, and dust attenuation.
Quick stats
- 659,229 galaxies in the catalog
- 650,599 with valid stellar mass estimates
- 650,599 with valid SFR estimates
- 340,258 classified as star-forming (log sSFR > -11)
- 310,341 classified as quiescent
- Median stellar mass: 10^{10.81} solar masses
- Median redshift: 0.1039
Schema
Usage
from datasets import load_dataset
ds = load_dataset("juliensimon/gswlc-galaxy-properties", split="train")
df = ds.to_pandas()
# Star-forming galaxies
sf = df[df["is_star_forming"]]
# Massive quiescent galaxies
massive_quiescent = df[(df["log_mstar"] > 11) & (~df["is_star_forming"])]
# Star formation main sequence
import matplotlib.pyplot as plt
valid = df[df["log_sfr_sed"].notna() & df["log_mstar"].notna()]
plt.hexbin(valid["log_mstar"], valid["log_sfr_sed"], gridsize=100, mincnt=1)
plt.xlabel("log M* (Msun)")
plt.ylabel("log SFR (Msun/yr)")
plt.title("Star Formation Main Sequence")
# Dusty galaxies (high FUV attenuation)
dusty = df[df["a_fuv"] > 3.0]
# Cross-match with SDSS using objidData source
GSWLC-2 — Salim et al. (2016, 2018).
- Salim et al. (2016), "GALEX-SDSS-WISE Legacy Catalog (GSWLC): Star Formation Rates, Stellar Masses, and Dust Attenuations of 700,000 Low-Redshift Galaxies", ApJS, 227, 2. arXiv:1610.00712
- Salim et al. (2018), "Dust Attenuation Curves in the Local Universe: Demographics and New Laws for Star-forming Galaxies and High-redshift Analogs", ApJ, 859, 11. arXiv:1804.05850
Related datasets
- galaxy-zoo-2-morphology — Galaxy Zoo 2 visual morphological classifications
- open-ngc — NGC/IC galaxy and nebula catalog
Pipeline
Source code: juliensimon/space-datasets
Citation
@dataset{gswlc_galaxy_properties,
author = {Simon, Julien},
title = {GSWLC-2 Galaxy Properties},
year = {2026},
publisher = {Hugging Face},
url = {https://huggingface.co/datasets/juliensimon/gswlc-galaxy-properties},
note = {Based on GSWLC-2 data (Salim et al. 2016, ApJS 227, 2; Salim et al. 2018, ApJ 859, 11)}
}