[AstroPy] [ANN] new astropy-affiliated package for spherical geometry

[Perry Greenfield]

We are pleased to announce the availability of a new astropy affiliated package.

spherical_geometry is a package for handling spherical polygons that represent arbitrary regions on the sky, and being able to manipulate such regions with operations such as computing the intersection or unions of such regions, testing to see if coordinates lie within a region, and computing region areas. It also allows computing distances between points, midpoints in such cases, angles and intersection points between great circles, and other related utilities.

All the coordinates in spherical_geometry are represented as unit vectors, thus avoiding the usual problems encountered near the poles when manipulating celestial coordinates.

The package provides means to convert to and from a celestial coordinate system. Which system is not important so long as consistency is used when converting back to the same coordinate system as was used initially.

This package has been developed by Mike Droettboom,  and ported to be astropy compatible by Bernie Simon, with significant testing and bug finding by Mihai Cara and Pey-Lian Lim

For more details, see the github repository and associated README: https://github.com/spacetelescope/sphere.

The documentation is located at: http://spacetelescope.github.io/sphere/spherical_geometry/

The current version is v1.0.4