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 Astronomical Data Repositories support upload, query, preview, and download of most FITS optical/NIR observations and include services like Trailblazer, an open data repository of astronomical images containing satellite trails, which should launch in early 2022. They must also encompass wavelengths outside optical/ NIR including radio, space-based observations from observatories in LEO, non-image data products including spectra, and other formats including visual sightings/ DSLR images. Broad participation in SatHub is critical to minimizing duplicated effort and disseminate current impacts from a rapidly changing LEO satellite population.

3.1.2. Build a Training Curriculum

Sharing data products and establishing SatHub are critical, but we must also train observers of all kinds to contribute to the global LEO satellite monitoring campaign. To accomplish this, we outline a training curriculum that can be adapted to suit a variety of observers. It includes a core curriculum with an introductory module and modules on observing satellites, reporting/sharing observations, and image/ data analyses. In addition, we outline advanced modules: software development, radio astronomy, and laws governing outer space. Finally, it will include appendices with Quick Start Recipes for astrophotographers, smaller telescope users, and larger research-grade telescope users, as well as links to related citizen science projects.

3.1.3. Best Practices for Operator Public Data Sharing

The position of a satellite at a future time is forecast with a propagator algorithm that uses an orbital solution from the recent past. The SATCON1 Report concluded that it is essential for satellite operators to provide prompt, accurate, updated, and publicly available orbital solution data in a standardized way. To achieve this, we propose and justify four key implementation steps:


 * 1) Operators should publicly provide orbital solutions every 8 hours or whenever a maneuver happens, whichever is first, and must include reasonable estimates of uncertainties with all orbital solutions.
 * 2) In addition to orbital solutions, operators should publicly provide any other relevant metadata that may assist observers in assessing impacts on observations at all wavelengths. These may include, but are not limited to, reflectivity, bidirectional reflectance distribution function (BRDF), effective isotropic radiated power (EIRP), transmission bandpasses, and nominal flux density at different frequencies.
 * 3) Operators should adopt standard formats for both ephemeris-style orbital solutions (state vectors of position and velocity data) and general perturbation-style orbital solutions (time-averaged Keplerian elements that include atmospheric drag that are presently provided in TLE format). We suggest a format like the plain text NASA Modified ITC Ephemeris format that SpaceX presently uses for the former, and strongly endorse the Celestrak-recommended Orbit Mean-Elements (OMM) format from Consultative Committee for Space Data Systems (CCSDS) 502.0-B-2 for the latter.
 * 4) We must promptly establish a public Orbital Solution Portal website as part of SatHub. Satellite operators should pay for the hosting and upkeep of this website. It should retain rather than overwrite past orbital solutions and provide an easy lookup interface for data retrieval, and it should include an open source software tool that allows users to translate between ephemerides, general perturbations in the new OMM format, and old-style TLEs.

SATCON1 noted that new software tools will be critical to dealing with the challenge of observing in the era of satellite constellations. The Algorithms WG considered the specific approaches recommended by SATCON1 and developed them into specific high-level software requirements. Each of the proposed packages will take a great deal of time and effort to create, partly because of the complexity of the problem they need to solve, and partly because they must serve multiple communities with varying levels of software familiarity. The group emphasizes that in the end no set of software tools will allow astronomers to fully recover the data affected by satellite trails. The WG recommends that a number of specific software efforts are needed, and while the entire community is expected to contribute, 7