juliensimon/tgss-radio-catalog

TGSS Alternative Data Release 1 (150 MHz)

The TIFR GMRT Sky Survey Alternative Data Release 1 (TGSS ADR1), a 150 MHz radio continuum survey covering 90% of the sky (declination > -53 deg) using the Giant Metrewave Radio Telescope. Contains 623,604 discrete radio sources, filling the critical low-frequency gap in all-sky radio catalogs.

Dataset description

TGSS ADR1 is the largest 150 MHz radio survey, observed between 2010 and 2012 with the GMRT. It provides 25 arcsecond resolution and a median rms noise of ~3.5 mJy/beam. The catalog is essential for low-frequency radio spectral studies, identifying steep-spectrum sources such as pulsars, high-redshift radio galaxies, and galaxy cluster relics.

Schema

Column	Type	Description
source_name	string	TGSS source designation
ra_deg	float64	Right ascension J2000 (degrees)
dec_deg	float64	Declination J2000 (degrees)
peak_flux_mjy	float64	Peak flux density (mJy/beam)
integrated_flux_mjy	float64	Integrated flux density (mJy)
e_peak_flux_mjy	float64	Error on peak flux (mJy/beam)
e_integrated_flux_mjy	float64	Error on integrated flux (mJy)
rms_mjy	float64	Local rms noise (mJy/beam)
major_axis_arcsec	float64	Fitted major axis FWHM (arcsec)
minor_axis_arcsec	float64	Fitted minor axis FWHM (arcsec)
position_angle_deg	float64	Position angle (degrees)

Quick stats

• 623,604 radio sources at 150 MHz
• Median peak flux: 768.00 mJy/beam
• Median rms noise: 0.00 mJy/beam
• Sky coverage: RA 0.0--360.0 deg, Dec -53.1--89.6 deg

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/tgss-radio-catalog", split="train")
df = ds.to_pandas()

# Flux distribution
import matplotlib.pyplot as plt
df["peak_flux_mjy"].clip(upper=500).hist(bins=200, log=True)
plt.xlabel("Peak flux at 150 MHz (mJy/beam)")
plt.ylabel("Count")
plt.title("TGSS Source Flux Distribution")
plt.show()

# Sky coverage
plt.scatter(df["ra_deg"], df["dec_deg"], s=0.01, alpha=0.1)
plt.xlabel("RA (deg)")
plt.ylabel("Dec (deg)")
plt.title("TGSS ADR1 Sky Coverage (150 MHz)")
plt.show()

# Bright sources (> 1 Jy)
bright = df[df["integrated_flux_mjy"] > 1000]
print(f"{len(bright):,} sources brighter than 1 Jy at 150 MHz")

Data source

Intema, H.T., Jagannathan, P., Mooley, K.P., and Frail, D.A. (2017), The GMRT 150 MHz all-sky radio survey -- First alternative data release TGSS ADR1. Astronomy & Astrophysics, 598, A78. Via VizieR CDS Strasbourg.

Pipeline

Source code: juliensimon/space-datasets

Citation

@dataset{tgss_radio_catalog,
  author = {Simon, Julien},
  title = {TGSS Alternative Data Release 1 (150 MHz)},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/tgss-radio-catalog},
  note = {Based on Intema et al. (2017) via VizieR CDS Strasbourg}
}

License

CC-BY-4.0