Built on good science.

The data and software inside the app.

Licenses

The notices these licenses ask us to reproduce, as they appear in the app under Settings → Acknowledgements.

Astral Journey is built on the following. Thank you to their authors.

NIRAYANA
Planetary positions, sidereal time, rise and set, eclipses.
https://github.com/nirayana/nirayana

MIT License

Copyright (c) 2026 The Nirayana authors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

NASA JPL DE440 EPHEMERIS
The bundled kernel de440s.bsp is from NASA's Jet Propulsion Laboratory.
Park, R. S., Folkner, W. M., Williams, J. G., and Boggs, D. H. (2021), The JPL Planetary and Lunar
Ephemerides DE440 and DE441, The Astronomical Journal 161:105. https://doi.org/10.3847/1538-3881/abd414

ERFA (ESSENTIAL ROUTINES FOR FUNDAMENTAL ASTRONOMY) 2.0.1
Parts of ERFA are included in Nirayana. ERFA is derived from the IAU's SOFA library; this app uses
a library derived from SOFA, not SOFA itself.

Copyright (C) 2013-2021, NumFOCUS Foundation.
All rights reserved.

This library is derived, with permission, from the International
Astronomical Union's "Standards of Fundamental Astronomy" library,
available from http://www.iausofa.org.

The ERFA version is intended to retain identical
functionality to the SOFA library, but made distinct through
different function and file names, as set out in the SOFA license
conditions. The SOFA original has a role as a reference standard
for the IAU and IERS, and consequently redistribution is permitted only
in its unaltered state. The ERFA version is not subject to this
restriction and therefore can be included in distributions which do not
support the concept of "read only" software.

Although the intent is to replicate the SOFA API (other than replacement of
prefix names) and results (with the exception of bugs; any that are
discovered will be fixed), SOFA is not responsible for any errors found
in this version of the library.

If you wish to acknowledge the SOFA heritage, please acknowledge that
you are using a library derived from SOFA, rather than SOFA itself.


TERMS AND CONDITIONS

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1 Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

2 Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

3 Neither the name of the Standards Of Fundamental Astronomy Board, the
   International Astronomical Union nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

DELTA T
Historical Delta T spline coefficients: L. V. Morrison, F. R. Stephenson, C. Y. Hohenkerk and
M. Zawilski, Addendum 2020 to Measurement of the Earth's rotation: 720 BC to AD 2015, Proceedings
of the Royal Society A 477:20200776 (2021), https://doi.org/10.1098/rspa.2020.0776. Numerical dataset
version 2 (https://doi.org/10.6084/m9.figshare.13885863.v2), licensed under Creative Commons
Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/). Converted to program
literals without changing any epoch bounds or coefficients.
Modern monthly Delta T values: U.S. Naval Observatory, IERS Rapid Service/Prediction Center
(https://maia.usno.navy.mil/products/deltaT), approved for public release, distribution unlimited.

GEONAMES
Place names, coordinates and time zones for offline search from GeoNames (https://www.geonames.org),
licensed under Creative Commons Attribution 4.0 International
(https://creativecommons.org/licenses/by/4.0/). Changed: filtered to places of 15,000 or more
people and reduced to name, region, country, coordinates and time zone.