juliensimon/messier-catalog

Messier Catalog

Credit: NASA/ESA/Hubble

Part of a dataset collection on Hugging Face.

Dataset description

The complete Messier catalog of 110 deep-sky objects -- galaxies, nebulae, and star clusters visible from the Northern Hemisphere. From SIMBAD.

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.

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.

This dataset is suitable for tabular classification tasks.

Schema

Column	Type	Description	Sample	Null %
name	string	Primary SIMBAD resolved name (e.g. 'NGC 224' for M31, 'Crab Nebula' for M1); may be an NGC/IC number or common name	M 1	0.0%
ra_deg	float64	Right ascension in decimal degrees, ICRS J2000.0; range 0-360	83.6324	0.0%
dec_deg	float64	Declination in decimal degrees, ICRS J2000.0; range -90 to +90	22.0174	0.0%
object_type	string	Raw SIMBAD object type code (e.g. 'GlC' = globular cluster, 'G' = galaxy, 'SNR' = supernova remnant, 'OpC' = open cluster, 'HII' = emission nebula, 'PN' = planetary nebula)	SNR	0.0%
major_axis_arcmin	float64	Major axis apparent angular size in arcminutes; range ~1 arcmin (M76) to ~95 arcmin (M31 Andromeda Galaxy); null for point-like or unresolved objects	7.0	5.4%
minor_axis_arcmin	float64	Minor axis apparent angular size in arcminutes; null for circular or point-like objects	5.0	5.4%
messier_number	int64	Numeric Messier catalog index; range 1-110; all 110 canonical objects included	1	0.0%
messier_id	string	Messier catalog designation with space separator (e.g. 'M 1', 'M 110'); used as primary label for the 110 canonical deep-sky objects	M 1	0.0%
object_category	string	Human-readable category derived from SIMBAD type: 'Galaxy', 'Globular Cluster', 'Open Cluster', 'Planetary Nebula', 'Supernova Remnant', etc.	Supernova Remnant	0.0%

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()

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)]
print(f"{len(galaxies)} galaxies in the Messier catalog")

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

# Sky map of Messier objects
import matplotlib.pyplot as plt
fig, ax = plt.subplots(figsize=(10, 5), subplot_kw={"projection": "aitoff"})
import numpy as np
ra_rad = np.deg2rad(df["ra_deg"] - 180)
dec_rad = np.deg2rad(df["dec_deg"])
ax.scatter(ra_rad, dec_rad, s=20, alpha=0.8)
ax.set_title("Messier Objects on the Sky")
ax.grid(True)
plt.tight_layout()
plt.show()

Data source

https://simbad.u-strasbg.fr/

Related datasets

• juliensimon/ngc-ic-catalog

• juliensimon/quasar-catalog

• juliensimon/black-hole-catalog

If you find this dataset useful, please consider giving it a like on Hugging Face. It helps others discover it.

About the author

Created by Julien Simon — AI Operating Partner at Fortino Capital. Part of the Space Datasets collection.

Citation

@dataset{messier_catalog,
  title = {Messier Catalog},
  author = {juliensimon},
  year = {2026},
  url = {https://huggingface.co/datasets/juliensimon/messier-catalog},
  publisher = {Hugging Face}
}

License

CC-BY-4.0