asteroid_spinprops 1.0.0

Collection of tools used for fitting sHG1G2 and SOCCA photometric models to sparse asteroid photometry

asteroid-spinprops

Overview

asteroid-spinprops is a Python package providing tools to fit SHG1G2 and SOCCA photometric models to sparse asteroid photometry.
It supports multiband modeling, residual analysis and shape, period and pole orientation estimation for small solar system objects.

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Installation

Install the package via pip:

pip install asteroid_spinprops

Quick Start

import numpy as np
import pandas as pd
from asteroid_spinprops.ssolib import dataprep, periodest, modelfit

# Suppose `pdf` is your initial asteroid DataFrame 
# Ensure all columns are converted to the required single row format.
pdf_s = pd.DataFrame({col: [np.array(pdf[col])] for col in pdf.columns})

# Convert filter IDs to numeric
unique_vals, inv = np.unique(pdf_s["cfid"].values[0], return_inverse=True)
numeric_filter = inv + 1
pdf_s["cfid"].values[0] = numeric_filter

# --- Data cleaning and filtering ---
clean_data, errorbar_rejects = dataprep.errorbar_filtering(data=pdf_s, mlimit=0.7928)
clean_data, projection_rejects = dataprep.projection_filtering(data=clean_data)
clean_data, iterative_rejects = dataprep.iterative_filtering(data=clean_data)

# --- Fit SHG1G2 model ---
shg1g2_params = modelfit.get_fit_params(
    data=clean_data,
    flavor="SHG1G2",
)

# Compute residuals for period analysis
residuals_dataframe = modelfit.make_residuals_df(
    clean_data, model_parameters=shg1g2_params
)

# --- Estimate rotation period ---
p_in, k_val, p_rms, signal_peak, window_peak = periodest.get_multiband_period_estimate(
    residuals_dataframe,
    k_free=True,
)

# Assess period robustness via bootstrap resampling
_, Nbs = periodest.perform_residual_resampling(
    resid_df=residuals_dataframe,
    p_min=0.03,
    p_max=2,
    k=int(k_val)
)

# --- Fit SSHG1G2 (spin + multiband) model ---
SOCCA_params = modelfit.get_fit_params(
    data=clean_data,
    flavor="SSHG1G2",
    shg1g2_constrained=True,
    blind_scan=True,
    period_in=p_in,
)

Models

Photometric models from Carry et al.(2024) {2024A&A...687A..38C} and https://github.com/astrolabsoftware

Project status

Under development