The package libTheSky provides a Fortran library to compute the positions of celestial bodies (Sun, Moon, planets, stars, asteroids, comets)
and events (e.g. lunar phases) with great accuracy. libTheSky can use different reference frames (heliocentric, geocentric, topocentric) and coordinate systems
(ecliptic, equatorial, galactic; spherical, rectangular). Much of the code is based on Meeus, Astronomical Algorithms, 1998;
however, the user has the choice between his low-accuracy, cheap calculations for Sun and Moon,
and the full and highly accurate VSOP87 and ELP 2000-82B theories.
This package, together with libSUFR,
has been developed for and forms the core of the software that is used to create the Flemish/Dutch popular-astronomy website
hemel.waarnemen.com. It can be used under the conditions of version 3 of the
libTheSky is written in Fortran and has been shown to compile with
g95 (both free and open-source) and
In order to compile and run, the package needs the Fortran library
The default installer uses
CMake, but you can use
your own Makefile or compile and install the code by hand.
The code needs data files as input for the calculations (planetary and lunar theory, orbital elements, star databases, etc.).
All but one are included in the tarball. The file asteroids.dat is not included, since it is about eight times the size of
the other files combined, and it can be downloaded from the NASA JPL website.
A reduced file, containing the brightest 25% of the minor planets from the database (a<100 AU, H<15; >90,000 bodies) can be found
Please see the INSTALL file in the tarball for details.
libTheSky has been used by:
You can contact the developer through
(produced by codes using libTheSky)