license: cc-by-4.0
pretty_name: SDSS-based Asteroid Taxonomy
language:
- en
description: >-
Compositional taxonomy for 107,466 SDSS observations of 63,468 asteroids, with
ugriz reflectances and orbital elements.
task_categories:
- tabular-classification
- tabular-regression
tags:
- space
- asteroids
- taxonomy
- composition
- sdss
- orbital-mechanics
- open-data
- tabular-data
size_categories:
- 100K<n<1M
configs:
- config_name: default
data_files:
- split: train
path: data/sdss_asteroid_taxonomy.parquet
default: true
SDSS-based Asteroid Taxonomy
Part of the Orbital Mechanics Datasets collection on Hugging Face.
Compositional taxonomy for 107,466 SDSS photometric observations of 63,468 asteroids, classified using the scheme of Carvano et al. (2010). Each observation includes SDSS u'g'r'i'z' log-reflectances, a taxonomic class assignment, and a probability score. Orbital elements from the asteroid catalog are merged in for asteroids with known orbits.
Dataset description
The Sloan Digital Sky Survey (SDSS) Moving Object Catalog observed over 100,000 asteroids in five photometric bands (u', g', r', i', z') between 1998 and 2007. Carvano et al. (2010) developed a probabilistic taxonomic classification scheme based on SDSS colors, assigning each observation to one of nine primary compositional classes inspired by the Bus taxonomy:
- V — Basaltic (V-type)
- O — Olivine-rich (O-type)
- Q — Ordinary chondrite-like (Q-type)
- S — Silicaceous (S-complex)
- A — Strongly reddened (A-type)
- L — Moderately reddened (L-type)
- D — Very red, organic-rich (D-type)
- X — Degenerate featureless (X-complex)
- C — Carbon-rich, featureless (C-complex)
When an observation falls near a class boundary, a two-letter compound class is assigned (e.g., SQ, CX, LS) indicating ambiguity between the two types. Each observation receives a probability score (0--100) for the assigned class.
The classification column gives the best overall class per asteroid (from the asteroid
summary table), chosen as either the most frequent or highest-scoring class across all
SDSS observations of that object.
Schema
| Column | Type | Description |
|---|---|---|
object_id |
string | Primary identifier (asteroid number or provisional designation) |
ast_number |
Int64 | IAU asteroid catalog number (null for unnumbered) |
ast_name |
string | IAU asteroid name (null if unnamed) |
prov_desig |
string | Provisional designation at discovery |
tax_class |
string | Taxonomic class for this observation (C/S/V/Q/D/L/X/A/O or compound e.g. SQ/CX) |
score |
Int64 | Probability score for assigned class (0-100) |
moid |
string | Unique SDSS moving-object observation ID |
bad_flag |
Int64 | 1 if any magnitude uncertainty exceeds 3rd quartile |
log_refl_u |
float64 | Log reflectance, SDSS u' band |
log_refl_err_u |
float64 | Uncertainty of u' log reflectance |
log_refl_g |
float64 | Log reflectance, SDSS g' band (reference = 1.0) |
log_refl_err_g |
float64 | Uncertainty of g' log reflectance |
log_refl_r |
float64 | Log reflectance, SDSS r' band |
log_refl_err_r |
float64 | Uncertainty of r' log reflectance |
log_refl_i |
float64 | Log reflectance, SDSS i' band |
log_refl_err_i |
float64 | Uncertainty of i' log reflectance |
log_refl_z |
float64 | Log reflectance, SDSS z' band |
log_refl_err_z |
float64 | Uncertainty of z' log reflectance |
classification |
string | Best overall class for this asteroid (most frequent or highest score) |
score_best |
Int64 | Probability score for best classification |
n_class |
Int64 | Number of classified SDSS observations for this asteroid |
method |
Int64 | 1 = most frequent class chosen, 0 = highest score chosen |
sequence |
string | Sequence of per-observation class assignments |
abs_mag_h |
float64 | Absolute magnitude H from SDSS MOC |
proper_semimajor_au |
float64 | Proper semi-major axis (AU), null if unavailable |
proper_eccentricity |
float64 | Proper eccentricity, null if unavailable |
sin_proper_inclination |
float64 | Sine of proper inclination, null if unavailable |
osc_semimajor_au |
float64 | Osculating semi-major axis (AU) |
osc_eccentricity |
float64 | Osculating eccentricity |
osc_inclination_deg |
float64 | Osculating inclination (degrees) |
Quick stats
- 107,466 observations of 63,468 unique asteroids
- 33 taxonomic classes
- Top classes: C (28,784), S (25,713), LS (8,956), L (8,129), X (6,003)
- 78,180 observations with orbital elements
Usage
from datasets import load_dataset
ds = load_dataset("juliensimon/sdss-asteroid-taxonomy", split="train")
df = ds.to_pandas()
# Class distribution
df["tax_class"].value_counts().plot.bar()
# Taxonomic composition vs semi-major axis (main belt structure)
import matplotlib.pyplot as plt
belt = df[df["osc_semimajor_au"].between(2.0, 3.5)]
for cls in ["S", "C", "X", "V"]:
subset = belt[belt["tax_class"] == cls]
plt.hist(subset["osc_semimajor_au"], bins=100, alpha=0.5, label=cls, density=True)
plt.xlabel("Semi-major axis (AU)")
plt.legend()
# High-confidence V-type (basaltic) asteroids
vesta_family = df[(df["tax_class"] == "V") & (df["score"] > 80)]
# SDSS color-color diagram
plt.scatter(df["log_refl_r"] - df["log_refl_i"],
df["log_refl_g"] - df["log_refl_r"],
c=df["tax_class"].astype("category").cat.codes, s=0.2, alpha=0.3)
Data source
PDS Small Bodies Node — SDSS-based Asteroid Taxonomy V1.1
Based on SDSS Moving Object Catalog observations (1998-2007). See Carvano et al. (2010) and Ivezic et al. (2010).
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{sdss_asteroid_taxonomy,
author = {Simon, Julien},
title = {SDSS-based Asteroid Taxonomy},
year = {2026},
publisher = {Hugging Face},
url = {https://huggingface.co/datasets/juliensimon/sdss-asteroid-taxonomy},
note = {Based on Carvano et al. (2010) SDSS taxonomy from the PDS Small Bodies Node}
}