Fetching TLEs

This package defines a simple API to fetch TLEs from different sources. For more information, see the file API.md in the directory ./src/fetcher/.

It already contains the support to Celestrak. To fetch TLEs from this source, we first need to create the fetcher object:

julia> f = create_tle_fetcher(CelestrakTleFetcher)CelestrakTleFetcher("https://celestrak.org/NORAD/elements/gp.php")

Afterward, we can fetch the TLEs using the function fetch_tles:

julia> fetch_tles(f, satellite_name = "AMAZONIA 1")[ Info: Fetch TLEs from Celestrak using satellite name: "AMAZONIA 1" ...
1-element Vector{TLE}:
 TLE: AMAZONIA 1 (Epoch = 2025-01-01T12:02:46.117)

This function will always return a Vector{TLE}.

For Celestrak fetcher, the following options are available:

• international_designator::Union{Nothing, AbstractString}: International designator using the Celestrak format YYYY-NNN, where YYYY is the launch year, and the NNN is the launch number. (Default: nothing)
• satellite_number::Union{Nothing, Number}: Satellite catalog number (NORAD). (Default = nothing)
• satellite_name::Union{Nothing, AbstractString}: Satellite name. Notice that the system will search for all satellites whose name contains this string. (Default: nothing)

Thus, if we want to know, for example, all the satellites that were launched by the same rocket, we can search by the international designator as follows:

julia> fetch_tles(f, international_designator = "2021-015")[ Info: Fetch TLEs from Celestrak using international designator: "2021-015" ...
2-element Vector{TLE}:
 TLE: AMAZONIA 1 (Epoch = 2025-01-01T12:02:46.117)
 TLE: OBJECT B (Epoch = 2025-01-01T08:43:34.900)