A Python Package for Small-Body Planetary Astronomy
National Aeronautics and Space Administration
Planetary Data Archiving, Restoration, and Tools Program
External Partners
- University of Maryland
Project Description
NOTE: The original Institutional PI of this project was Jian Yang Li. On May 21, 2024 the Institutional PI was to Henry Hsieh when Li joined the faculty of Sun Yat-sen University in China.
As part of the developement effort of a dedicated Python package for small-body planetary astronomy, we will provide functionality to the development of software used to analyze emission lines from cometary comae, simulating synthetic spectra, photometric tools, and implementing a calculation of ephemerides using SPICE kernels in Python.
For the period covered under this proposal,
• We will provide routines for fitting emission line and reflectance spectra as part of the spectroscopy module of the package. These tools will also simulating synthetic spectra to derive outgassing and excitation parameters in cometary coma. The module will provide functions to interactively fit and remove continuum baseline, as well as to fit emission lines or reflectance spectra. Python code for the reduction and analysis of cometary spectra that is used for ground-based observations will be implemented in the sbpy package.
• A number of light scattering models for asteroidal surfaces and cometary coma dust will be implemented. The goal of the photometry module is to provide a facility to fit light scattering models to observed brightness data of asteroids, and to estimate the brightness of asteroids and cometary comae under specified geometry based on scattering models. Specifically, we plan to include a number of disk-integrated phase function models for asteroids, bidirectional reflectance (I/F) models of particulate surfaces, and phase functions of dust grains in cometary
comae.
• We will add functionality to calculate ephemerides of comets and asteroids from SPICE kernels using existing wrappers for the C implementation of the SPICE library. This tool is useful to identify when an object is observable during observation planning and for data analysis.
The required SPICE kernels will be downloade from the NASA’s Navigation and Ancillary Information Facility (NAIF) at the Jet Propulsion Laboratory or the Horizons on-line ephemeris system. SPICE kernels contain physical, dynamical and cartographic constants of small irregularly-shaped bodies, such as size and shape specifications that will be used by the 3-dimensional shape module to be developed as part of this proposal.