This is an initial release of the editor for the "map.txt" file from Endless Sky. It allows you to create and edit star systems and planets. If you want to compile it from the source code, you will need to install Qt 5.
Ubuntu packages are available in a PPA; Mac OS X and Windows files are available for download here. The Windows download should work on 64-bit WIndows and may also work on 32-bit Windows (although that has not been tested yet).