juliensimon/bus-demeo-asteroid-taxonomy

Bus-DeMeo Asteroid Taxonomy

Part of the Astronomy Datasets collection on Hugging Face.

The Bus-DeMeo taxonomy is the current standard classification system for asteroids based on their visible and near-infrared reflectance spectra (0.45--2.45 um). This dataset contains the 371 reference asteroids used to define and validate the taxonomy, each classified into one of 31 taxonomic classes grouped into 13 complexes.

Dataset description

The Bus-DeMeo system (DeMeo et al. 2009) extended the earlier Bus taxonomy into the near-infrared, using principal component analysis on reflectance spectra to define 24 taxonomic classes. Each class corresponds to distinct surface mineralogy: S-complex asteroids are silicate-rich (olivine/pyroxene), C-complex are carbonaceous, X-complex have featureless spectra (metal-rich or enstatite), and end-member types (V, A, D, K, etc.) have unique spectral signatures.

This dataset is the reference classification set -- the 371 asteroids whose spectra were used to define and validate the taxonomy. It includes the taxonomic class, observation date, spectral slope, and the five principal component scores from the PCA decomposition.

Schema

Column	Type	Description
asteroid_number	int	IAU asteroid catalog number
asteroid_name	string	Asteroid name (e.g., "Ceres", "Vesta")
provisional_designation	string	MPC provisional designation
taxonomic_class	string	Bus-DeMeo class (e.g., S, C, Sq, Xk, V); 'w' suffix = slope >0.25; ':' = uncertain
taxonomic_complex	string	Broad grouping: S, C, X, or end-member letter
obs_date	date	Date of spectroscopic observation
ref_code	string	Literature reference code (a--i)
spectral_slope	float64	Slope of the linear regression to the reflectance spectrum
pc1	float64	First principal component score
pc2	float64	Second principal component score
pc3	float64	Third principal component score
pc4	float64	Fourth principal component score
pc5	float64	Fifth principal component score

Quick stats

• 371 asteroids in the reference taxonomy set
• 31 distinct taxonomic classes, 13 broad complexes
• Most common classes: S (102), Sw (42), L (22), Ch (18), Xk (17)
• 334 with IAU names, 371 with principal component scores

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/bus-demeo-asteroid-taxonomy", split="train")
df = ds.to_pandas()

# Class distribution
print(df["taxonomic_class"].value_counts())

# Complex distribution
print(df["taxonomic_complex"].value_counts())

# PC1 vs PC2 scatter plot colored by complex
import matplotlib.pyplot as plt
for cpx in ["S", "C", "X", "V"]:
    sub = df[df["taxonomic_complex"] == cpx].dropna(subset=["pc1", "pc2"])
    plt.scatter(sub["pc1"], sub["pc2"], label=cpx, alpha=0.6, s=15)
plt.xlabel("PC1")
plt.ylabel("PC2")
plt.legend()
plt.title("Bus-DeMeo Taxonomy: PC1 vs PC2 by Complex")

Data source

DeMeo F.E., Binzel R.P., Slivan S.M., Bus S.J. (2009), "An extension of the Bus asteroid taxonomy into the near-infrared", Icarus, 202, 160--180. Accessed via PDS Small Bodies Node (urn:nasa:pds:ast.bus-demeo.taxonomy::1.0).

Related datasets

• neo-close-approaches -- Near-Earth Object close approaches
• asteroid-sbdb -- JPL Small-Body Database
• meteorite-landings -- Meteorite Landings

Pipeline

Source code: juliensimon/space-datasets

Citation

@dataset{bus_demeo_asteroid_taxonomy,
  author = {Simon, Julien},
  title = {Bus-DeMeo Asteroid Taxonomy},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/bus-demeo-asteroid-taxonomy},
  note = {Based on DeMeo et al. (2009, Icarus 202, 160) via PDS Small Bodies Node}
}

License

CC-BY-4.0