The CPL comprises a set of ISO-C libraries that provide a comprehensive, efficient and robust software toolkit to develop astronomical data-reduction tasks (known as recipes). These data-reduction tasks can then be executed manually by a user, or can be triggered in an automated data-reduction framework (known as pipelines) which are used at ESO to monitor the health status of VLT instruments, for quick-look data processing at the observatory, and the creation of data products available from the ESO archive facility.

This package provides a Python definition and validation schemata for FITS files.

This package provides an way to compute dendrograms of observed or simulated Astronomical data in Python.

This package provides a librari for spherical harmonic transforms (SHTs), which evolved from the libpsht library, addressing several of its shortcomings, such as adding MPI support for distributed memory systems and SHTs of fields with arbitrary spin, but also supporting new developments in CPU instruction sets like the Advanced Vector Extensions (AVX) or fused multiply-accumulate (FMA) instructions. The library is implemented in portable C99 and provides an interface that can be easily accessed from other programming languages such as C++, Fortran, Python etc. Generally, libsharp's performance is at least on par with that of its predecessor; however, significant improvements were made to the algorithms for scalar SHTs, which are roughly twice as fast when using the same CPU capabilities.

Supporting paper is available at https://arxiv.org/abs/1303.4945

Cesium is an end-to-end machine learning platform for time-series, from calculation of features to model-building to predictions. Cesium has two main components - a Python library, and a web application platform that allows interactive exploration of machine learning pipelines. Take control over the workflow in a Python terminal or Jupyter notebook with the Cesium library, or upload your time-series files, select your machine learning model, and watch Cesium do feature extraction and evaluation right in your browser with the web application.

STWCS provides support for WCS distortion models and coordinate transformation for the imaging instruments on the Hubble Space Telescope).

The FITS "World Coordinate System" (WCS) standard defines keywords and usage that provide for the description of astronomical coordinate systems in a FITS (Flexible Image Transport System) image header.

aiapy is a Python package for analyzing data from the AIA instrument onboard NASA's SDO spacecraft.

The iers package provides access to the tables provided by the International Earth Rotation and Reference Systems service, in particular the Earth Orientation data allowing interpolation of published UT1-UTC and polar motion values for given times. The UT1-UTC values are used in Time and Dates (astropy.time) to provide UT1 values, and the polar motions are used in astropy.coordinates to determine Earth orientation for celestial-to-terrestrial coordinate transformations.

skyfield computes positions for the stars, planets, and satellites in orbit around the Earth. Its results should agree with the positions generated by the United States Naval Observatory and their Astronomical Almanac to within 0.0005 arcseconds (half a mas or milliarcsecond).

SunPy is package for solar physics and is meant to be a free alternative to the SolarSoft data analysis environment.

It includes an interface for searching and downloading data from multiple data providers, data containers for image and time series data, commonly used solar coordinate frames and associated transformations, as well as other functionality needed for solar data analysis.

Software for Calibrating AstroMetry and Photometry is a software that computes astrometric projection parameters from source catalogues derived from FITS images. The computed solution is expressed according to the WCS standard. The main features of SCAMP are:

• compatibility with SExtractor FITS or Multi-Extension FITS catalogue format in input

• generation of WCS-compliant and SWarp-compatible FITS image headers in output

• automatic grouping of catalogues on the sky

• selectable on-line astrometric reference catalogue

• automatic determination of scale, position angle, flipping and coordinate shift using fast pattern-matching

• various astrometric calibration modes for single detectors and detector arrays

• combined astrometric solutions for multi-channel/instrument surveys

• highly configurable astrometric distortion polynomials

• correction for differential chromatic refraction

• proper motion measurements

• multi-threaded code that takes advantage of multiple processors

• VOTable-compliant XML output of meta-data

• XSLT filter sheet provided for convenient access to metadata from a regular web browser

madrigalWeb is a pure python module to access data from any Madrigal database.

Madrigal is an upper atmospheric science database used by groups throughout the world. Madrigal is a robust, World Wide Web based system capable of managing and serving archival and real-time data, in a variety of formats, from a wide range of upper atmospheric science instruments. Data at each Madrigal site is locally controlled and can be updated at any time, but shared metadata between Madrigal sites allow searching of all Madrigal sites at once from any Madrigal site.

This package provides a functionality to reproject astronomical images using various techniques via a uniform interface, where reprojection is the re-gridding of images from one world coordinate system to another e.g. changing the pixel resolution, orientation, coordinate system.

MissFITS is a program that performs basic maintenance and packaging tasks on FITS files:

• add/edit FITS header keywords

• split/join MEF files

• unpack/pack FITS data-cubes

• create/check/update FITS checksums, using R. Seaman's protocol

Python read-only implementation of the EventIO file format.

CCfits is an object oriented interface to the cfitsio library. It is designed to make the capabilities of cfitsio available to programmers working in C++. It is written in ANSI C++ and implemented using the C++ Standard Library with namespaces, exception handling, and member template functions.

hvpy is a Python API wrapper around the formal https://api.helioviewer.org/docs/v2/.

PyERFA is the Python wrapper for the ERFA library (Essential Routines for Fundamental Astronomy), a C library containing key algorithms for astronomy, which is based on the SOFA library published by the International Astronomical Union (IAU). All C routines are wrapped as Numpy universal functions, so that they can be called with scalar or array inputs.

Stackistry implements the lucky imaging principle of astronomical imaging: creating a high-quality still image out of a series of many (possibly thousands) low quality ones (blurred, deformed, noisy). The resulting image stack typically requires post-processing, including sharpening (e.g. via deconvolution). Such post-processing is not performed by Stackistry.

This package provides a pure Python tooling for ionospheric analyses in radio astronomy, e.g. getting total electron content and rotation measure.

specutils is a Python package for representing, loading, manipulating,and analyzing astronomical spectroscopic data. The generic data containers and accompanying modules provide a toolbox that the astronomical community can use to build more domain-specific packages. For more details about the underlying principles, see APE13.

CFITSIO provides simple high-level routines for reading and writing Flexible Image Transport System files that insulate the programmer from the internal complexities of the FITS format. CFITSIO also provides many advanced features for manipulating and filtering the information in FITS files.

PyCPL provides Python3 language bindings for the complete programming API of the European Southern Observatory Common Pipeline Library toolkit, including the CPL plugin interface.