ASTRA

Welcome to the repository of ASTRA (Astrophysical Spectral Tools for Retrieval & Analysis).

The main goal of this project is to standardize the handling of stellar spectra for both RV extraction tools and spectral analysis tools. In order to do so, ASTRA provides:

1. Common interface to interact with stellar spectra of different state-of-the-art instruments
2. Framework to construct stellar templates from data, following best practices
3. Framework to mask telluric features from stellar spectra
4. Implement utility methods to interpolate, normalize and smooth stellar spectra

For information on installation, usage, and contribution check the official documentation.

If you use it, please cite the paper:

@ARTICLE{2026JOSS...11.9413S,
       author = {{Silva}, Andr{\'e} and {Faria}, J. and {Santos}, Nuno and {Sousa}, S{\'e}rgio and {Viana}, Pedro and {Martins}, J.},
        title = "{ASTRA: A Python Package for Cross-Instrument Stellar and Telluric Template Construction}",
      journal = {The Journal of Open Source Software},
     keywords = {astronomy, Python, Cython, Instrumentation and Methods for Astrophysics, Earth and Planetary Astrophysics, Solar and Stellar Astrophysics},
         year = 2026,
        month = jan,
       volume = {11},
       number = {117},
          eid = {9413},
        pages = {9413},
          doi = {10.21105/joss.09413},
archivePrefix = {arXiv},
       eprint = {2601.10439},
 primaryClass = {astro-ph.IM},
       adsurl = {https://ui.adsabs.harvard.edu/abs/2026JOSS...11.9413S},
      adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

Installation

ASTRA is currently available in python 3.11 and python 3.12, and it can be installed either through

1. Pypi

pip install ASTRA-spectra

2. Github

git clone git@github.com:Kamuish/ASTRA.git
cd ASTRA
pip install . 

By default, ASTRA does not install Telfit as it will only be needed for the masking of the telluric features. If this is the goal, it must be installed manually.

Contribution guidelines

Management of any issues to the code, as well as external contribution is done through the github repository