This repository contains a dataset of Two Line Element (TLE) data for 15 satellites. Its purpose is to serve as a benchmark dataset for studies examining changes in satellite orbits over larger time scales. It also contains the ground-truth manoeuvre timestamps for these satellites. Highly-accurate positional data from DORIS ground beacons is also included for some satellites.
Please see the paper: Wide-scale Monitoring of Satellite Lifetimes: Pitfalls and a Benchmark Dataset for a detailed description of the dataset.
The following table lists the satellites in the dataset:
| Name | SATCAT Number | First Manoeuvre | Last Manoeuvre |
|---|---|---|---|
| Fengyun-2D | 29640 | 2011-02-01 | 2015-04-10 |
| Fengyun-2E | 33463 | 2011-03-17 | 2018-10-15 |
| Fengyun-2F | 38049 | 2012-09-11 | 2022-01-05 |
| Fengyun-2H | 43491 | 2019-01-18 | 2022-01-18 |
| Fengyun-4A | 41882 | 2018-05-22 | 2022-02-21 |
| Sentinel-3A | 41335 | 2016-02-23 | 2022-10-07 |
| Sentinel-3B | 43437 | 2018-05-01 | 2022-10-07 |
| Sentinel-6A | 46984 | 2020-11-24 | 2022-10-14 |
| Jason-1 | 26997 | 2001-12-12 | 2013-06-14 |
| Jason-2 | 33105 | 2008-06-24 | 2019-10-05 |
| Jason-3 | 41240 | 2016-01-20 | 2022-10-11 |
| SARAL | 39086 | 2013-02-28 | 2022-09-22 |
| CryoSat-2 | 36508 | 2010-04-16 | 2022-10-06 |
| Haiyang-2A | 37781 | 2011-09-29 | 2020-06-10 |
| TOPEX | 22076 | 1992-08-18 | 2004-11-18 |
The folder processed_files contains the TLE files as well as the manoeuvre timestamps. The TLE files conform to the
TLE standard as defined by NORAD. A good starting point for working with them
is the Skyfield library
Some brief advice on getting started using Skyfield in conjunction with this data. You can use the
tle_file() function to load the TLE file into a list of Skyfield
EarthSatellite objects.
(see here
for some general documentation on loading TLE files). Each EarthSatellite object is associated with the data published for one
satellite epoch, which corresponds with a pair of lines in the original TLE file. One can call the .at() function on
these objects to get the satellite position in cartesian geocentric coordinates. One can then use the
osculating_elements_of() function
to convert this position into osculating keplerian elements. Moreover, by providing times other than the published epoch to the
at() function, it can also perform propagation of the position and osculating elements to different points in time. If one
is interested in monitoring changes in satellite orbits over longer time scales (weeks to years), we suggest that using the
at() function is counter-productive, due to the fact that it uses models of orbiting satellites to add in non-Keplerian
components of the orbit. This is discussed in detail in the paper Wide-scale Monitoring of Satellite Lifetimes: Pitfalls and a Benchmark Dataset.
Rather, we suggest using the mean Keplerian elements that are presented in the raw TLE records. One can still use Skyfield
to conveniently load and manipulate the data. The mean Keplerian elements are stored as instance variables of the model variable of
each EarthSatellite object. Note that these mean elements are also propagated and updated each time the at() method
is called on the EarthSatellite object.
The manoeuvre timestamps are stored in YAML files, also found in the directory processed_files.
These files also contain the satellite's SATCAT number
as a piece of useful metadata. The timestamps are stored in an item named manoeuvre_timestamps. This is a list of
strings of ISO8601 timestamps which contain the UTC time and
date of each manoeuvre.
The accurate positional data from the DORIS ground beacons is stored in the DORIS_beacon_positions directory in CSV files.
The directory plotting contains the scripts for creating the plots in the paper
Wide-scale Monitoring of Satellite Lifetimes: Pitfalls and a Benchmark Dataset.
plotting_TLE_propagation_residuals.pycreates the plots in figures 2, 11, 12 and 13.plotting_osculating_mean_and_DORIS.pycreates the plots in figure 3.plotting_osculating_and_mean_diffs_distribution.pycreates the plots in figure 4.plotting_osculating_propagation_to_mean_diff.pycreates the plots in figure 5.plot_satellite_liftimes_gantt.pycreates the plot in figure 6.plotting_propagation_accuracy_TLE_to_SP3.pycreates the plots in figure 7.plotting_DORIS_fourier_analysis.pycreates the plots in figures 8, 9 and 10.
The directory utilities contains some useful scripts for inspecting the data.
you will need to change the file paths in params.py.
The directory dataset_formatting contains scripts for manipulating the raw data into the compiled files.