Satelles

Modern, type-safe, zero-dependency python library for TLE, OMM et al. handling and orbit propagation to accurately locate your satellites in the sky.

Installation

We recommend using uv to manage your Python environments.

To install satelles into your uv environment, run:

uv add satelles

Alternatively, you can install satelles using your preferred environment or package manager of choice, e.g., poetry, conda, or pip:

pip install satelles

poetry add satelles

conda install satelles

Usage

from datetime import datetime, timezone

from satelles import TLE

issTLE: str = """        
  1 25544U 98067A   20062.59097222  .00016717  00000-0  10270-3 0  9006
  2 25544  51.6442 147.1064 0004607  95.6506 329.8285 15.49249062  2423
"""

satellite = TLE(tle_string=issTLE).as_satellite()

satellite.at(when=datetime(2021, 5, 15, 0, 0, 0, tzinfo=timezone.utc))

# Get the Earth Centric Inertial (ECI) coordinate of the satellite at the given time:
eci = satellite.eci_coordinate

# Get the Equatorial Coordinate of the satellite at the given time:
equatorial = satellite.equatorial_coordinate
...

As the API is fully typed, you can use your IDE's autocompletion to see all the available methods and properties.

We have also provided further usage examples in the examples directory.

Milestones

• Type-safe modern 3.6+ Python
• Fully unit tested
• Simpler API using Pydantic base models for validation
• Zero-external dependencies (pure Python 3.6+ with no external C/C++ dependencies)
• Example API usage
• Fully supported Two-Line Element (TLE) parsing and operations
• Fully supported Orbital Mean Elements Message (OMM) parsing and operations
• Fully supported TLE to OMM conversion
• Fully supported laser ranging formats (e.g., CPF and CRD).
• Fully supported Earth Centred-Earth Fixed (ECEF) to East-North-Up (ENU) conversion
• Fully supported Earth Centric Inertial (ECI) to Equatorial Coordinate System (ECS) conversion
• Fully supported Earth Centric Inertial (ECI) to Topocentric Coordinate System (TCS) conversion
• Fully supported SPG4-XP propagation from TLE or OMM
• Fully supported symplectic Verlet numerical propagation
• Fully supported Runge-Kutta 4th order numerical propagation
• Modified Julian Date utilities

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License

This project is licensed under the terms of the MIT license. See the LICENSE file for details.