Swift-Sgp4 on Calogero Sanfilippo

SGPKit 3.1.0 released

Sun, 09 Nov 2025 08:23:45 +0100

A new version of SGPKit, 3.1.0, has been released.

This new minor version introduces the conformance to Codable for the TLE type. This allows easy serialization and deserialization of TLE objects.

Encoding Link to heading

import SGPKit

let tle = try TLE(
 title: "ISS (ZARYA)",
 firstLine: "1 25544U 98067A 25312.54791667 .00016717 00000-0 10270-3 0 9006",
 secondLine: "2 25544 51.6432 123.4567 0007417 234.5678 345.6789 15.50000012345678"
)

let encoder = TLEEncoder()

let data: Data = try encoder.encode(tle)

print("Encoded TLE data: \(data)")

Decoding Link to heading

Decoding a single TLE is quite simple.

SGPKit 3.0.0 released

Mon, 27 Oct 2025 22:04:55 +0100

Version 3.0.0 of swift-sgp4 is now available.
This release introduces support for Linux and Android, expahunding the library beyond Apple platforms.

Background Link to heading

swift-sgp4 provides Swift bindings to the SGP4 orbital propagation library.
Earlier versions relied on an Objective-C++ wrapper around the C++ implementation, which limited the project to iOS and macOS.

What Changed Link to heading

Objective-C++ wrapper removed
The previous bridge was tied to Apple platforms and prevented portability.

SGPKit 1.3.1 released

Tue, 21 Oct 2025 17:51:55 +0200

Version 1.3.1 of SPGKit has been released.

This update resolves a build configuration issue that affected projects using Swift 5.9.
In previous versions, the package failed to compile because the Swift Package Manager setup did not correctly handle the interoperability between Swift and C++ sources. As a result, users on Swift 5.9 encountered build errors when integrating the library.

The fix applies the proper configuration for Swift/C++ interop, following the approach described in the Swift documentation. With this adjustment, the package now builds successfully on Swift 5.9 and later.

SGPKit 1.2.1 released

Mon, 06 Oct 2025 22:35:24 +0200

🚀 A new bugfix release of SGPKit is now available: v1.2.1.

This update adopts the latest upstream code from dnwrnr/sgp4, ensuring better alignment with the reference implementation.

If you’re using SGPKit in your Swift-based satellite tracking or orbital analysis tools, it’s recommended to upgrade to 1.2.1 for improved reliability.

For full details, check out the release notes.

swift-sgp4 on Swift Package Index

Sun, 10 Jul 2022 23:52:10 +0200

swift-sgp4 is available through Swift Package Index.

Swift Package Index is a search engine for packages that support the Swift Package Manager.

swift-sgp4 1.0.0 is here!

Sun, 03 Jul 2022 23:52:10 +0200

Today I released the first open source version of swift-sgp4, a very simple Swift Package that calculates the position of a satellite given a two-line elements set (TLE).

The library wouldn’t have been possible without the fundamental help of sgp4, a satellite prediction C++ library developed by Daniel Warner.

As you may imagine, swift-sgp4 is the core of [ISSSeeker]({{ site.url }}/apps/issseeker).