juliensimon/messier-catalog

Messier Catalog

Part of the Astronomy Datasets collection on Hugging Face.

The complete Messier catalog — 93 deep-sky objects catalogued by Charles Messier in the 18th century. Includes 25 galaxies, 44 star clusters, and 7 nebulae/remnants.

Dataset description

The Messier catalog holds a singular place in the history of astronomy. Charles Messier, an 18th-century French comet hunter, compiled this list of "nebulous objects" specifically to avoid confusing them with comets during his searches. Ironically, the catalog he intended as a nuisance list became one of the most celebrated collections in astronomy, encompassing some of the most spectacular and scientifically important objects visible from the Northern Hemisphere. The 110 entries span nearly every major class of deep-sky object: giant elliptical and spiral galaxies, globular and open star clusters, planetary nebulae, supernova remnants, and star-forming regions.

Many Messier objects are cornerstones of modern astrophysics. M 31 (the Andromeda Galaxy) is the nearest large spiral galaxy to the Milky Way and the object that first demonstrated the existence of "island universes" beyond our own Galaxy. M 1 (the Crab Nebula) is the remnant of the supernova of 1054 AD and hosts one of the most studied pulsars in the sky. M 87 harbors the first black hole ever directly imaged by the Event Horizon Telescope. Globular clusters like M 13 and M 3 contain some of the oldest stars in the universe and constrain the age of the Milky Way. Open clusters such as the Pleiades (M 45) and Praesepe (M 44) serve as fundamental calibrators for stellar evolution theory and the cosmic distance ladder.

Despite its small size, the Messier catalog remains the standard introduction to deep-sky observing and is widely used in education, outreach, and the annual "Messier Marathon" -- an attempt to observe all 110 objects in a single night near the spring equinox. For researchers, it provides a well-characterized sample of bright, nearby objects with extensive multi-wavelength data across the electromagnetic spectrum, from radio to gamma-ray.

Schema

Column	Type	Description
messier_id	string	Messier designation (M 1, M 2, ...)
messier_number	int	Messier number (1-110)
name	string	Primary SIMBAD name (e.g. "NGC 224", "Crab Nebula")
ra_deg	float	Right ascension (degrees)
dec_deg	float	Declination (degrees)
object_type	string	SIMBAD object type code
object_category	string	Human-readable category (Galaxy, Globular Cluster, etc.)
major_axis_arcmin	float	Major axis angular size (arcmin)
minor_axis_arcmin	float	Minor axis angular size (arcmin)

Quick stats

• 93 Messier objects
• 25 galaxies, 44 star clusters, 7 nebulae/remnants

Usage

from datasets import load_dataset

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

# Galaxies only
galaxies = df[df["object_category"].str.contains("Galaxy", na=False)]

# Objects by category
df["object_category"].value_counts()

Update frequency

Updated quarterly via GitHub Actions.

Data source

SIMBAD Astronomical Database (CDS, Strasbourg).

Related datasets

• ngc-ic-catalog — 14K deep-sky objects (NGC + IC)
• quasar-catalog — 50K quasars and AGN
• black-hole-catalog — Known black hole systems

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{messier_catalog,
  author = {Simon, Julien},
  title = {Messier Catalog},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/messier-catalog},
  note = {Based on SIMBAD astronomical database (CDS Strasbourg)}
}