Ephemeris Calculation Core

What is intended for publication

The Developer Kit contains the Python production core and the unmodified DE440s kernel. Individual language packages contain source and help, but no compilers, runtimes, tests or precomputed N16 data. The separate N16 generator downloads its source data directly from JPL Horizons on the user's computer.

The language inventory names all 286 reviewed language entries and records our decision for each one. External catalog aliases, search rules and scoring values are not copied.

Source-only

Downloads

Public filenames remain stable. Version, size and SHA-256 are shown on this page.

Complete review scope

Inventory of all programming languages found

The table covers all 286 language names in the frozen audit. It shows which language was implemented, whether its port caused a problem, and why a target was not considered or was not considered separately.

“Not tested” in the issue column means that no port was run. Consolidated language families are explicitly marked as “not considered separately”.

Command line

CLI parameters

The 49 language packages are library sources and have no common stable command line. The optional N16 generator and its verifier are the two command-line tools in this source release.

Parameters for the complete Windows application are listed on its separate application CLI page.

Generate N16 data

Ephemeris-N16-Generator [--start DATE] [--stop DATE]
  [--output DIRECTORY] [--refresh] [--request-delay SECONDS]
  [--sample-step-days DAYS]
  [--keep-source-spk | --remove-source-spk]
  [--verify] [--licenses] [--data-terms] [--version]

Each platform ZIP contains a self-contained command-line application, README.txt and a prominent English N16 quick start. Python, CSPICE and a separate .NET installation are not required.

Use N16 in a language core

In addition to n16-states-f64.bin, the generator automatically writes nine directly usable files below core-data/n16. Copy that complete directory as n16 next to the existing planets directory. Pass the common parent as the data root to the language core and enable includeN16.

ephemeris-data/
  planets/
    de440s-2000-2004.bin
    ...
  n16/
    n16-2000-2004.bin
    ...
    n16-2040-2040.bin
    index.json

The N16 generator does not create planet files. The planets directory must already be complete. The English manual in each language package documents its exact API.

Verify N16 data

Ephemeris-N16-Generator --verify --output DIRECTORY

Without a directory, the verifier uses the same platform-specific default as the generator. It checks the manifest, file sizes and checksums without modifying data.

Method and formulae

Scientific article

The article explains time conversion, gravitational parameters, universal Kepler propagation, Dormand-Prince 5(4) integration, perturbing accelerations, light time, observer corrections, extreme cases and the language comparison. This is the complete English edition, not a browser translation of the German document.

Clear separation

License and data sources

Project-authored, marked source code is offered under the Apache License 2.0. Every package contains LICENSE, NOTICE, LICENSE-SCOPE.md, THIRD-PARTY-NOTICES.md and DATA-SOURCES-AND-TERMS.md.

The unmodified DE440s kernel remains a NAIF/JPL data product and is not represented as Apache-licensed project source. The N16 package contains only the generator; precomputed N16 data and Horizons object SPKs are not distributed.

Release history

Versions and security

N16 generator 0.5.5 – separate German and English CLI packages
Windows x64/ARM64, Linux x64/ARM64 and macOS Intel/Apple Silicon; directly usable core-data/n16 chunks and localized README and quick-start files.

0.5.3 – release
49 validated language packages, 343 alternating timing measurements, 602 German and English document files and 17 passed license checks.

0.5.3 – complete language inventory
A separate tab lists all 286 reviewed language names with implementation status, issue flag and a concise English reason.

0.5.3 – documentation state
Equivalent German and English scientific articles with a defined gravitational parameter, explained technical terminology, portrait tables and separate accuracy and speed comparisons.

0.5.3 – license state
Apache-2.0 marking of project source, source-only packages and a separate N16 generator without a precomputed state table.

Checksums and malware scanning

SHA-256 is provided for every download. The language packages contain source and documents, but no executable compiler or installer files. The six N16 platform archives, however, contain self-contained CLI programs. They were submitted to VirusTotal on 27 July 2026 with the SHA-256 values published here: Windows x64, Windows ARM64, Linux x64, Linux ARM64, macOS Intel and macOS Apple Silicon. Results can still be incomplete immediately after submission.

Legal information

Legal notice

Information pursuant to Section 5 DDG

Jost Jahn
Smaeswai 4
25946 Nebel
Germany

Email: Ephemeris@jostjahn.de

Amrum Software is a project and collective name for the software offerings of Jost Jahn.

Liability and copyright

Content has been prepared with care. No warranty is given for accuracy, completeness or timeliness. External website content is the sole responsibility of its respective operator.

Original content and source components are subject to the stated license terms. Rights and terms for external data sources, runtimes, compilers and documentation remain unaffected.

Privacy

Privacy notice

Controller: Jost Jahn, Smaeswai 4, 25946 Nebel, Germany, Ephemeris@jostjahn.de.

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Under the STRATO hosting setup, IP addresses in logs are anonymized and normally stored for 60 days unless a specific security investigation requires longer retention. The recipient is strato.de.

Local preferences, downloads and external links

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Contact, recipients and rights

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